From a96494df86e49543494710b0b059c47fa4f0e0d3 Mon Sep 17 00:00:00 2001
From: Maxim Orlov <m.orlov@postgrespro.ru>
Date: Fri, 11 Mar 2022 11:37:29 +0300
Subject: [PATCH v40 8/8] Use 64-bit XIDs

- change TransactionId to 64bit
- disk tuple format (HeapTupleHeader) is (almost) unchanged: xmin and xmax remains 32bit
  -- now 32bit xid is named ShortTransactionId
- heap page format is changed to contain xid and multixact base value, tuple's
  xmin and xmax are offsets from.
  -- xid_base and multi_base are stored as a page special data. PageHeader remains unmodified.
- in-memory tuple (HeapTuple) were enriched with precalulated 64bit xmin/xmax.

Authors:
- Alexander Korotkov <aekorotkov@gmail.com>
- Teodor Sigaev <teodor@sigaev.ru>
- Nikita Glukhov <n.gluhov@postgrespro.ru>
- Maxim Orlov <orlovmg@gmail.com>
- Pavel Borisov <pashkin.elfe@gmail.com>
- Yura Sokolov <y.sokolov@postgrespro.ru> <funny.falcon@gmail.com>
- Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://postgr.es/m/CACG%3DezZe1NQSCnfHOr78AtAZxJZeCvxrts0ygrxYwe%3DpyyjVWA%40mail.gmail.com
Discussion: https://postgr.es/m/CAJ7c6TPDOYBYrnCAeyndkBktO0WG2xSdYduTF0nxq%2BvfkmTF5Q%40mail.gmail.com
---
 contrib/amcheck/verify_heapam.c               |   79 +-
 contrib/amcheck/verify_nbtree.c               |    2 +-
 contrib/hstore/hstore_io.c                    |    2 +
 contrib/pageinspect/Makefile                  |    3 +-
 contrib/pageinspect/btreefuncs.c              |   22 +-
 contrib/pageinspect/expected/btree.out        |    4 +-
 contrib/pageinspect/expected/hash_1.out       |  166 +++
 .../pageinspect/expected/oldextversions.out   |   10 +-
 contrib/pageinspect/expected/page.out         |   28 +-
 contrib/pageinspect/heapfuncs.c               |    9 +-
 .../pageinspect/pageinspect--1.10--1.11.sql   |  145 ++
 contrib/pageinspect/pageinspect--1.5.sql      |    2 +
 contrib/pageinspect/pageinspect.control       |    2 +-
 contrib/pageinspect/rawpage.c                 |   37 +-
 contrib/pageinspect/sql/btree.sql             |    3 +-
 contrib/pg_surgery/heap_surgery.c             |   21 +-
 .../pg_visibility/expected/pg_visibility.out  |   17 +
 contrib/pg_visibility/pg_visibility.c         |    6 +-
 contrib/pg_visibility/sql/pg_visibility.sql   |   18 +
 contrib/pgrowlocks/pgrowlocks.c               |    2 +-
 contrib/pgstattuple/pgstatapprox.c            |    2 +
 contrib/pgstattuple/pgstatindex.c             |    2 +-
 .../postgres_fdw/expected/postgres_fdw.out    |   55 +-
 contrib/postgres_fdw/postgres_fdw.c           |    9 +-
 contrib/postgres_fdw/sql/postgres_fdw.sql     |   15 +-
 src/backend/access/common/heaptuple.c         |    8 +-
 src/backend/access/common/reloptions.c        |  118 +-
 src/backend/access/hash/hashvalidate.c        |    5 +-
 src/backend/access/heap/heapam.c              | 1174 +++++++++++++++--
 src/backend/access/heap/heapam_handler.c      |   34 +-
 src/backend/access/heap/heapam_visibility.c   |  173 +--
 src/backend/access/heap/heaptoast.c           |    3 +
 src/backend/access/heap/hio.c                 |   46 +-
 src/backend/access/heap/pruneheap.c           |   82 +-
 src/backend/access/heap/rewriteheap.c         |   93 +-
 src/backend/access/heap/vacuumlazy.c          |  148 +--
 src/backend/access/nbtree/nbtpage.c           |    2 +
 src/backend/access/nbtree/nbtsplitloc.c       |   16 +-
 src/backend/access/nbtree/nbtxlog.c           |    2 +
 src/backend/access/rmgrdesc/gistdesc.c        |    4 +-
 src/backend/access/rmgrdesc/heapdesc.c        |   32 +
 src/backend/access/rmgrdesc/mxactdesc.c       |    9 +-
 src/backend/access/rmgrdesc/nbtdesc.c         |    4 +-
 src/backend/access/rmgrdesc/xactdesc.c        |    6 +-
 src/backend/access/rmgrdesc/xlogdesc.c        |    6 +-
 src/backend/access/transam/clog.c             |   24 +-
 src/backend/access/transam/commit_ts.c        |   19 -
 src/backend/access/transam/multixact.c        |  686 +---------
 src/backend/access/transam/slru.c             |   13 +-
 src/backend/access/transam/subtrans.c         |    9 +-
 src/backend/access/transam/transam.c          |   18 +-
 src/backend/access/transam/twophase.c         |   15 +-
 src/backend/access/transam/varsup.c           |  161 +--
 src/backend/access/transam/xact.c             |   36 +-
 src/backend/access/transam/xlog.c             |   10 +-
 src/backend/access/transam/xloginsert.c       |    7 +
 src/backend/access/transam/xlogreader.c       |   34 -
 src/backend/access/transam/xlogrecovery.c     |    2 +-
 src/backend/bootstrap/bootstrap.c             |   26 +-
 src/backend/catalog/heap.c                    |    8 +-
 src/backend/catalog/pg_inherits.c             |    2 +-
 src/backend/commands/async.c                  |    2 +-
 src/backend/commands/dbcommands.c             |    9 +-
 src/backend/commands/indexcmds.c              |    6 +-
 src/backend/commands/sequence.c               |   22 +-
 src/backend/commands/vacuum.c                 |   96 +-
 src/backend/executor/execExprInterp.c         |    1 +
 src/backend/executor/execUtils.c              |    1 +
 src/backend/executor/nodeModifyTable.c        |    1 +
 src/backend/executor/spi.c                    |    1 +
 src/backend/nodes/copyfuncs.c                 |    1 +
 src/backend/nodes/equalfuncs.c                |    8 +
 src/backend/nodes/outfuncs.c                  |    6 +-
 src/backend/optimizer/util/plancat.c          |    2 +-
 src/backend/postmaster/autovacuum.c           |   72 +-
 src/backend/replication/logical/decode.c      |   18 +-
 src/backend/replication/logical/proto.c       |   50 +-
 .../replication/logical/reorderbuffer.c       |   17 +-
 src/backend/replication/logical/snapbuild.c   |    4 +-
 src/backend/replication/logical/worker.c      |    2 +-
 src/backend/replication/pgoutput/pgoutput.c   |    3 +-
 src/backend/replication/walreceiver.c         |   28 +-
 src/backend/replication/walsender.c           |   73 +-
 src/backend/statistics/extended_stats.c       |    1 +
 src/backend/storage/buffer/Makefile           |    3 +-
 src/backend/storage/buffer/bufmgr.c           |   79 +-
 src/backend/storage/buffer/heap_convert.c     |  547 ++++++++
 src/backend/storage/ipc/procarray.c           |  181 +--
 src/backend/storage/ipc/sinvaladt.c           |    4 +-
 src/backend/storage/ipc/standby.c             |    6 +-
 src/backend/storage/lmgr/lmgr.c               |   16 +-
 src/backend/storage/lmgr/lock.c               |    4 +-
 src/backend/storage/lmgr/predicate.c          |    4 +-
 src/backend/storage/lmgr/proc.c               |   11 +-
 src/backend/storage/page/bufpage.c            |  254 +++-
 src/backend/tcop/postgres.c                   |   25 +-
 src/backend/utils/adt/enum.c                  |    2 +-
 src/backend/utils/adt/jsonfuncs.c             |    1 +
 src/backend/utils/adt/lockfuncs.c             |    9 +-
 src/backend/utils/adt/pgstatfuncs.c           |    1 +
 src/backend/utils/adt/rowtypes.c              |   12 +
 src/backend/utils/adt/xid.c                   |   37 +-
 src/backend/utils/adt/xid8funcs.c             |   83 +-
 src/backend/utils/cache/catcache.c            |    1 +
 src/backend/utils/cache/relcache.c            |    3 +-
 src/backend/utils/fmgr/fmgr.c                 |    4 +-
 src/backend/utils/misc/guc.c                  |  184 +--
 src/backend/utils/misc/help_config.c          |    8 +-
 src/backend/utils/misc/pg_controldata.c       |    2 +-
 src/backend/utils/misc/postgresql.conf.sample |    4 +-
 src/backend/utils/sort/tuplesort.c            |    8 +-
 src/backend/utils/time/combocid.c             |   18 +-
 src/backend/utils/time/snapmgr.c              |   19 +-
 src/bin/initdb/initdb.c                       |   60 +-
 src/bin/initdb/t/001_initdb.pl                |   12 +-
 src/bin/pg_amcheck/t/004_verify_heapam.pl     |  210 ++-
 src/bin/pg_controldata/pg_controldata.c       |    2 +-
 src/bin/pg_dump/pg_dump.c                     |   20 +-
 src/bin/pg_dump/pg_dump.h                     |    8 +-
 src/bin/pg_resetwal/pg_resetwal.c             |   56 +-
 src/bin/pg_upgrade/Makefile                   |    1 +
 src/bin/pg_upgrade/check.c                    |  114 ++
 src/bin/pg_upgrade/controldata.c              |   17 +-
 src/bin/pg_upgrade/file.c                     |  168 ++-
 src/bin/pg_upgrade/pg_upgrade.c               |  167 ++-
 src/bin/pg_upgrade/pg_upgrade.h               |   27 +-
 src/bin/pg_upgrade/segresize.c                |  586 ++++++++
 src/bin/pg_upgrade/t/002_pg_upgrade.pl        |   22 +-
 src/bin/pg_upgrade/version.c                  |  104 +-
 src/bin/pg_verifybackup/t/003_corruption.pl   |    2 +-
 src/bin/pg_waldump/pg_waldump.c               |    2 +-
 src/include/access/clog.h                     |    2 +-
 src/include/access/ginblock.h                 |   11 +-
 src/include/access/gist.h                     |    2 +-
 src/include/access/heapam.h                   |   22 +-
 src/include/access/heapam_xlog.h              |   37 +-
 src/include/access/heaptoast.h                |   11 +-
 src/include/access/htup.h                     |   18 +-
 src/include/access/htup_details.h             |  233 +++-
 src/include/access/multixact.h                |   11 +-
 src/include/access/nbtree.h                   |   10 +
 src/include/access/rewriteheap.h              |    4 +-
 src/include/access/rmgrlist.h                 |    1 +
 src/include/access/slru.h                     |   10 +-
 src/include/access/tableam.h                  |    2 +-
 src/include/access/transam.h                  |   89 +-
 src/include/access/tupmacs.h                  |    3 +-
 src/include/access/xact.h                     |   13 +-
 src/include/access/xloginsert.h               |    1 +
 src/include/access/xlogreader.h               |    4 -
 src/include/access/xlogrecord.h               |    5 +-
 src/include/c.h                               |   27 +-
 src/include/catalog/catversion.h              |    3 +-
 src/include/catalog/pg_amproc.dat             |    4 +-
 src/include/catalog/pg_control.h              |    6 +
 src/include/catalog/pg_operator.dat           |    8 +-
 src/include/catalog/pg_proc.dat               |   12 +-
 src/include/catalog/pg_type.dat               |    4 +-
 src/include/catalog/pg_type.h                 |    5 +
 src/include/commands/vacuum.h                 |   28 +-
 src/include/fmgr.h                            |    2 +
 src/include/nodes/pg_list.h                   |    4 +
 src/include/pg_config.h.in                    |    3 +
 src/include/postgres.h                        |    6 +-
 src/include/postmaster/autovacuum.h           |    4 +-
 src/include/storage/buf_internals.h           |    5 +-
 src/include/storage/bufmgr.h                  |    4 +
 src/include/storage/bufpage.h                 |  233 +++-
 src/include/storage/itemid.h                  |    2 +
 src/include/storage/lock.h                    |   14 +-
 src/include/storage/proc.h                    |    7 +-
 src/include/storage/standby.h                 |    2 +-
 src/include/utils/combocid.h                  |    2 +-
 src/include/utils/rel.h                       |   12 +-
 src/include/utils/xid8.h                      |    4 +-
 src/pl/plperl/plperl.c                        |    4 +-
 src/pl/plpgsql/src/pl_comp.c                  |    4 +-
 src/pl/plpgsql/src/pl_exec.c                  |    2 +
 src/pl/plpython/plpy_procedure.c              |    4 +-
 src/pl/tcl/pltcl.c                            |    4 +-
 src/test/Makefile                             |    3 +-
 src/test/perl/PostgreSQL/Test/Cluster.pm      |    4 +-
 src/test/recovery/t/003_recovery_targets.pl   |    2 +-
 src/test/regress/expected/indirect_toast.out  |    8 +
 src/test/regress/expected/insert.out          |   16 +-
 src/test/regress/expected/opr_sanity.out      |    6 +-
 src/test/regress/expected/select_views.out    |   70 +-
 src/test/regress/expected/txid.out            |    8 +-
 src/test/regress/expected/type_sanity.out     |    5 +-
 src/test/regress/expected/xid.out             |   14 +-
 src/test/regress/expected/xid64.out           |   92 ++
 src/test/regress/parallel_schedule            |    2 +-
 src/test/regress/pg_regress.c                 |    2 +-
 src/test/regress/regress.c                    |  290 ++++
 src/test/regress/sql/indirect_toast.sql       |   11 +
 src/test/regress/sql/insert.sql               |   17 +-
 src/test/regress/sql/select_views.sql         |    2 +-
 src/test/regress/sql/type_sanity.sql          |    5 +-
 src/test/regress/sql/xid64.sql                |   84 ++
 src/test/xid-64/Makefile                      |   22 +
 src/test/xid-64/README                        |   16 +
 src/test/xid-64/t/001_test_large_xids.pl      |   54 +
 src/test/xid-64/t/002_test_gucs.pl            |   79 ++
 src/test/xid-64/t/003_test_integrity.pl       |   58 +
 src/test/xid-64/t/004_test_relminmxid.pl      |   90 ++
 src/test/xid-64/t/005_stream_subxact.pl       |  100 ++
 src/test/xid-64/t/006_zeropage.pl             |   33 +
 src/tools/msvc/Solution.pm                    |    1 +
 src/tools/pgindent/typedefs.list              |    4 +-
 209 files changed, 6650 insertions(+), 2584 deletions(-)
 create mode 100644 contrib/pageinspect/expected/hash_1.out
 create mode 100644 contrib/pageinspect/pageinspect--1.10--1.11.sql
 create mode 100644 src/backend/storage/buffer/heap_convert.c
 create mode 100644 src/bin/pg_upgrade/segresize.c
 create mode 100644 src/test/regress/expected/xid64.out
 create mode 100644 src/test/regress/sql/xid64.sql
 create mode 100644 src/test/xid-64/Makefile
 create mode 100644 src/test/xid-64/README
 create mode 100644 src/test/xid-64/t/001_test_large_xids.pl
 create mode 100644 src/test/xid-64/t/002_test_gucs.pl
 create mode 100644 src/test/xid-64/t/003_test_integrity.pl
 create mode 100644 src/test/xid-64/t/004_test_relminmxid.pl
 create mode 100644 src/test/xid-64/t/005_stream_subxact.pl
 create mode 100644 src/test/xid-64/t/006_zeropage.pl

diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c
index 3bea8052d2..c6740bcf2c 100644
--- a/contrib/amcheck/verify_heapam.c
+++ b/contrib/amcheck/verify_heapam.c
@@ -17,6 +17,7 @@
 #include "access/multixact.h"
 #include "access/toast_internals.h"
 #include "access/visibilitymap.h"
+#include "catalog/catalog.h"
 #include "catalog/pg_am.h"
 #include "funcapi.h"
 #include "miscadmin.h"
@@ -85,7 +86,7 @@ typedef struct HeapCheckContext
 	 * from them.
 	 */
 	FullTransactionId next_fxid;	/* ShmemVariableCache->nextXid */
-	TransactionId next_xid;		/* 32-bit version of next_fxid */
+	TransactionId next_xid;		/* 64-bit version of next_fxid */
 	TransactionId oldest_xid;	/* ShmemVariableCache->oldestXid */
 	FullTransactionId oldest_fxid;	/* 64-bit version of oldest_xid, computed
 									 * relative to next_fxid */
@@ -126,6 +127,7 @@ typedef struct HeapCheckContext
 	uint16		lp_len;
 	uint16		lp_off;
 	HeapTupleHeader tuphdr;
+	HeapTupleData tuple;
 	int			natts;
 
 	/* Values for iterating over attributes within the tuple */
@@ -165,8 +167,6 @@ static bool check_tuple_visibility(HeapCheckContext *ctx);
 static void report_corruption(HeapCheckContext *ctx, char *msg);
 static void report_toast_corruption(HeapCheckContext *ctx,
 									ToastedAttribute *ta, char *msg);
-static FullTransactionId FullTransactionIdFromXidAndCtx(TransactionId xid,
-														const HeapCheckContext *ctx);
 static void update_cached_xid_range(HeapCheckContext *ctx);
 static void update_cached_mxid_range(HeapCheckContext *ctx);
 static XidBoundsViolation check_mxid_in_range(MultiXactId mxid,
@@ -390,7 +390,7 @@ verify_heapam(PG_FUNCTION_ARGS)
 	update_cached_xid_range(&ctx);
 	update_cached_mxid_range(&ctx);
 	ctx.relfrozenxid = ctx.rel->rd_rel->relfrozenxid;
-	ctx.relfrozenfxid = FullTransactionIdFromXidAndCtx(ctx.relfrozenxid, &ctx);
+	ctx.relfrozenfxid = FullTransactionIdFromXid(ctx.relfrozenxid);
 	ctx.relminmxid = ctx.rel->rd_rel->relminmxid;
 
 	if (TransactionIdIsNormal(ctx.relfrozenxid))
@@ -505,6 +505,12 @@ verify_heapam(PG_FUNCTION_ARGS)
 			ctx.tuphdr = (HeapTupleHeader) PageGetItem(ctx.page, ctx.itemid);
 			ctx.natts = HeapTupleHeaderGetNatts(ctx.tuphdr);
 
+			ctx.tuple.t_data = ctx.tuphdr;
+			ctx.tuple.t_len = ItemIdGetLength(ctx.itemid);
+			ctx.tuple.t_tableOid = RelationGetRelid(ctx.rel);
+			HeapTupleCopyBaseFromPage(&ctx.tuple, ctx.page,
+									  IsToastRelation(ctx.rel));
+
 			/* Ok, ready to check this next tuple */
 			check_tuple(&ctx);
 		}
@@ -730,12 +736,13 @@ check_tuple_visibility(HeapCheckContext *ctx)
 	XidCommitStatus xmin_status;
 	XidCommitStatus xvac_status;
 	XidCommitStatus xmax_status;
+	HeapTuple	tuple = &ctx->tuple;
 	HeapTupleHeader tuphdr = ctx->tuphdr;
 
 	ctx->tuple_could_be_pruned = true;	/* have not yet proven otherwise */
 
 	/* If xmin is normal, it should be within valid range */
-	xmin = HeapTupleHeaderGetXmin(tuphdr);
+	xmin = HeapTupleGetXmin(tuple);
 	switch (get_xid_status(xmin, ctx, &xmin_status))
 	{
 		case XID_INVALID:
@@ -745,19 +752,19 @@ check_tuple_visibility(HeapCheckContext *ctx)
 			report_corruption(ctx,
 							  psprintf("xmin %llu equals or exceeds next valid transaction ID %llu",
 									   (unsigned long long) xmin,
-									   (unsigned long long) U64FromFullTransactionId(ctx->next_fxid)));
+									   (unsigned long long) XidFromFullTransactionId(ctx->next_fxid)));
 			return false;
 		case XID_PRECEDES_CLUSTERMIN:
 			report_corruption(ctx,
 							  psprintf("xmin %llu precedes oldest valid transaction ID %llu",
 									   (unsigned long long) xmin,
-									   (unsigned long long) U64FromFullTransactionId(ctx->oldest_fxid)));
+									   (unsigned long long) XidFromFullTransactionId(ctx->oldest_fxid)));
 			return false;
 		case XID_PRECEDES_RELMIN:
 			report_corruption(ctx,
 							  psprintf("xmin %llu precedes relation freeze threshold %llu",
 									   (unsigned long long) xmin,
-									   (unsigned long long) U64FromFullTransactionId(ctx->relfrozenfxid)));
+									   (unsigned long long) XidFromFullTransactionId(ctx->relfrozenfxid)));
 			return false;
 	}
 
@@ -783,19 +790,19 @@ check_tuple_visibility(HeapCheckContext *ctx)
 					report_corruption(ctx,
 									  psprintf("old-style VACUUM FULL transaction ID %llu for moved off tuple equals or exceeds next valid transaction ID %llu",
 											   (unsigned long long) xvac,
-											   (unsigned long long) U64FromFullTransactionId(ctx->next_fxid)));
+											   (unsigned long long) XidFromFullTransactionId(ctx->next_fxid)));
 					return false;
 				case XID_PRECEDES_RELMIN:
 					report_corruption(ctx,
 									  psprintf("old-style VACUUM FULL transaction ID %llu for moved off tuple precedes relation freeze threshold %llu",
 											   (unsigned long long) xvac,
-											   (unsigned long long) U64FromFullTransactionId(ctx->relfrozenfxid)));
+											   (unsigned long long) XidFromFullTransactionId(ctx->relfrozenfxid)));
 					return false;
 				case XID_PRECEDES_CLUSTERMIN:
 					report_corruption(ctx,
 									  psprintf("old-style VACUUM FULL transaction ID %llu for moved off tuple precedes oldest valid transaction ID %llu",
 											   (unsigned long long) xvac,
-											   (unsigned long long) U64FromFullTransactionId(ctx->oldest_fxid)));
+											   (unsigned long long) XidFromFullTransactionId(ctx->oldest_fxid)));
 					return false;
 				case XID_BOUNDS_OK:
 					break;
@@ -849,19 +856,19 @@ check_tuple_visibility(HeapCheckContext *ctx)
 					report_corruption(ctx,
 									  psprintf("old-style VACUUM FULL transaction ID %llu for moved in tuple equals or exceeds next valid transaction ID %llu",
 											   (unsigned long long) xvac,
-											   (unsigned long long) U64FromFullTransactionId(ctx->next_fxid)));
+											   (unsigned long long) XidFromFullTransactionId(ctx->next_fxid)));
 					return false;
 				case XID_PRECEDES_RELMIN:
 					report_corruption(ctx,
 									  psprintf("old-style VACUUM FULL transaction ID %llu for moved in tuple precedes relation freeze threshold %llu",
 											   (unsigned long long) xvac,
-											   (unsigned long long) U64FromFullTransactionId(ctx->relfrozenfxid)));
+											   (unsigned long long) XidFromFullTransactionId(ctx->relfrozenfxid)));
 					return false;
 				case XID_PRECEDES_CLUSTERMIN:
 					report_corruption(ctx,
 									  psprintf("old-style VACUUM FULL transaction ID %llu for moved in tuple precedes oldest valid transaction ID %llu",
 											   (unsigned long long) xvac,
-											   (unsigned long long) U64FromFullTransactionId(ctx->oldest_fxid)));
+											   (unsigned long long) XidFromFullTransactionId(ctx->oldest_fxid)));
 					return false;
 				case XID_BOUNDS_OK:
 					break;
@@ -938,7 +945,7 @@ check_tuple_visibility(HeapCheckContext *ctx)
 		 * HEAP_XMAX_IS_LOCKED_ONLY is true, but for now we err on the side of
 		 * avoiding possibly-bogus complaints about missing TOAST entries.
 		 */
-		xmax = HeapTupleHeaderGetRawXmax(tuphdr);
+		xmax = HeapTupleGetRawXmax(tuple);
 		switch (check_mxid_valid_in_rel(xmax, ctx))
 		{
 			case XID_INVALID:
@@ -997,7 +1004,7 @@ check_tuple_visibility(HeapCheckContext *ctx)
 		 * We already checked above that this multixact is within limits for
 		 * this table.  Now check the update xid from this multixact.
 		 */
-		xmax = HeapTupleGetUpdateXid(tuphdr);
+		xmax = HeapTupleGetUpdateXid(tuple);
 		switch (get_xid_status(xmax, ctx, &xmax_status))
 		{
 			case XID_INVALID:
@@ -1009,19 +1016,19 @@ check_tuple_visibility(HeapCheckContext *ctx)
 				report_corruption(ctx,
 								  psprintf("update xid %llu equals or exceeds next valid transaction ID %llu",
 										   (unsigned long long) xmax,
-										   (unsigned long long) U64FromFullTransactionId(ctx->next_fxid)));
+										   (unsigned long long) XidFromFullTransactionId(ctx->next_fxid)));
 				return true;
 			case XID_PRECEDES_RELMIN:
 				report_corruption(ctx,
 								  psprintf("update xid %llu precedes relation freeze threshold %llu",
 										   (unsigned long long) xmax,
-										   (unsigned long long) U64FromFullTransactionId(ctx->relfrozenfxid)));
+										   (unsigned long long) XidFromFullTransactionId(ctx->relfrozenfxid)));
 				return true;
 			case XID_PRECEDES_CLUSTERMIN:
 				report_corruption(ctx,
 								  psprintf("update xid %llu precedes oldest valid transaction ID %llu",
 										   (unsigned long long) xmax,
-										   (unsigned long long) U64FromFullTransactionId(ctx->oldest_fxid)));
+										   (unsigned long long) XidFromFullTransactionId(ctx->oldest_fxid)));
 				return true;
 			case XID_BOUNDS_OK:
 				break;
@@ -1061,26 +1068,26 @@ check_tuple_visibility(HeapCheckContext *ctx)
 	}
 
 	/* xmax is an XID, not a MXID. Sanity check it. */
-	xmax = HeapTupleHeaderGetRawXmax(tuphdr);
+	xmax = HeapTupleGetRawXmax(tuple);
 	switch (get_xid_status(xmax, ctx, &xmax_status))
 	{
 		case XID_IN_FUTURE:
 			report_corruption(ctx,
 							  psprintf("xmax %llu equals or exceeds next valid transaction ID %llu",
 									   (unsigned long long) xmax,
-									   (unsigned long long) U64FromFullTransactionId(ctx->next_fxid)));
+									   (unsigned long long) XidFromFullTransactionId(ctx->next_fxid)));
 			return false;		/* corrupt */
 		case XID_PRECEDES_RELMIN:
 			report_corruption(ctx,
 							  psprintf("xmax %llu precedes relation freeze threshold %llu",
 									   (unsigned long long) xmax,
-									   (unsigned long long) U64FromFullTransactionId(ctx->relfrozenfxid)));
+									   (unsigned long long) XidFromFullTransactionId(ctx->relfrozenfxid)));
 			return false;		/* corrupt */
 		case XID_PRECEDES_CLUSTERMIN:
 			report_corruption(ctx,
 							  psprintf("xmax %llu precedes oldest valid transaction ID %llu",
 									   (unsigned long long) xmax,
-									   (unsigned long long) U64FromFullTransactionId(ctx->oldest_fxid)));
+									   (unsigned long long) XidFromFullTransactionId(ctx->oldest_fxid)));
 			return false;		/* corrupt */
 		case XID_BOUNDS_OK:
 		case XID_INVALID:
@@ -1555,24 +1562,6 @@ check_tuple(HeapCheckContext *ctx)
 	ctx->attnum = -1;
 }
 
-/*
- * Convert a TransactionId into a FullTransactionId using our cached values of
- * the valid transaction ID range.  It is the caller's responsibility to have
- * already updated the cached values, if necessary.
- */
-static FullTransactionId
-FullTransactionIdFromXidAndCtx(TransactionId xid, const HeapCheckContext *ctx)
-{
-	uint32		epoch;
-
-	if (!TransactionIdIsNormal(xid))
-		return FullTransactionIdFromEpochAndXid(0, xid);
-	epoch = EpochFromFullTransactionId(ctx->next_fxid);
-	if (xid > ctx->next_xid)
-		epoch--;
-	return FullTransactionIdFromEpochAndXid(epoch, xid);
-}
-
 /*
  * Update our cached range of valid transaction IDs.
  */
@@ -1586,7 +1575,7 @@ update_cached_xid_range(HeapCheckContext *ctx)
 	LWLockRelease(XidGenLock);
 
 	/* And compute alternate versions of the same */
-	ctx->oldest_fxid = FullTransactionIdFromXidAndCtx(ctx->oldest_xid, ctx);
+	ctx->oldest_fxid = FullTransactionIdFromXid(ctx->oldest_xid);
 	ctx->next_xid = XidFromFullTransactionId(ctx->next_fxid);
 }
 
@@ -1686,7 +1675,7 @@ get_xid_status(TransactionId xid, HeapCheckContext *ctx,
 	}
 
 	/* Check if the xid is within bounds */
-	fxid = FullTransactionIdFromXidAndCtx(xid, ctx);
+	fxid = FullTransactionIdFromXid(xid);
 	if (!fxid_in_cached_range(fxid, ctx))
 	{
 		/*
@@ -1695,7 +1684,6 @@ get_xid_status(TransactionId xid, HeapCheckContext *ctx,
 		 * performed the full xid conversion, reconvert.
 		 */
 		update_cached_xid_range(ctx);
-		fxid = FullTransactionIdFromXidAndCtx(xid, ctx);
 	}
 
 	if (FullTransactionIdPrecedesOrEquals(ctx->next_fxid, fxid))
@@ -1719,8 +1707,7 @@ get_xid_status(TransactionId xid, HeapCheckContext *ctx,
 	*status = XID_COMMITTED;
 	LWLockAcquire(XactTruncationLock, LW_SHARED);
 	clog_horizon =
-		FullTransactionIdFromXidAndCtx(ShmemVariableCache->oldestClogXid,
-									   ctx);
+		FullTransactionIdFromXid(ShmemVariableCache->oldestClogXid);
 	if (FullTransactionIdPrecedesOrEquals(clog_horizon, fxid))
 	{
 		if (TransactionIdIsCurrentTransactionId(xid))
diff --git a/contrib/amcheck/verify_nbtree.c b/contrib/amcheck/verify_nbtree.c
index 2beeebb163..67f5208ac3 100644
--- a/contrib/amcheck/verify_nbtree.c
+++ b/contrib/amcheck/verify_nbtree.c
@@ -525,7 +525,7 @@ bt_check_every_level(Relation rel, Relation heaprel, bool heapkeyspace,
 			 * avoid this.
 			 */
 			if (IsolationUsesXactSnapshot() && rel->rd_index->indcheckxmin &&
-				!TransactionIdPrecedes(HeapTupleHeaderGetXmin(rel->rd_indextuple->t_data),
+				!TransactionIdPrecedes(HeapTupleGetXmin(rel->rd_indextuple),
 									   snapshot->xmin))
 				ereport(ERROR,
 						(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
diff --git a/contrib/hstore/hstore_io.c b/contrib/hstore/hstore_io.c
index fb72bb6cfe..06648b22be 100644
--- a/contrib/hstore/hstore_io.c
+++ b/contrib/hstore/hstore_io.c
@@ -853,6 +853,7 @@ hstore_from_record(PG_FUNCTION_ARGS)
 		ItemPointerSetInvalid(&(tuple.t_self));
 		tuple.t_tableOid = InvalidOid;
 		tuple.t_data = rec;
+		HeapTupleSetZeroBase(&tuple);
 
 		values = (Datum *) palloc(ncolumns * sizeof(Datum));
 		nulls = (bool *) palloc(ncolumns * sizeof(bool));
@@ -1006,6 +1007,7 @@ hstore_populate_record(PG_FUNCTION_ARGS)
 		ItemPointerSetInvalid(&(tuple.t_self));
 		tuple.t_tableOid = InvalidOid;
 		tuple.t_data = rec;
+		HeapTupleSetZeroBase(&tuple);
 	}
 
 	/*
diff --git a/contrib/pageinspect/Makefile b/contrib/pageinspect/Makefile
index 5c0736564a..5ca80c9d76 100644
--- a/contrib/pageinspect/Makefile
+++ b/contrib/pageinspect/Makefile
@@ -13,7 +13,8 @@ OBJS = \
 	rawpage.o
 
 EXTENSION = pageinspect
-DATA =  pageinspect--1.9--1.10.sql pageinspect--1.8--1.9.sql \
+DATA = pageinspect--1.10--1.11.sql \
+	pageinspect--1.9--1.10.sql pageinspect--1.8--1.9.sql \
 	pageinspect--1.7--1.8.sql pageinspect--1.6--1.7.sql \
 	pageinspect--1.5.sql pageinspect--1.5--1.6.sql \
 	pageinspect--1.4--1.5.sql pageinspect--1.3--1.4.sql \
diff --git a/contrib/pageinspect/btreefuncs.c b/contrib/pageinspect/btreefuncs.c
index b18aa0af7f..f180ace787 100644
--- a/contrib/pageinspect/btreefuncs.c
+++ b/contrib/pageinspect/btreefuncs.c
@@ -105,9 +105,14 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat)
 
 	stat->page_size = PageGetPageSize(page);
 
+	stat->btpo_prev = opaque->btpo_prev;
+	stat->btpo_level = opaque->btpo_level;
+
 	/* page type (flags) */
 	if (P_ISDELETED(opaque))
 	{
+		TransactionId safexid;
+
 		/* We divide deleted pages into leaf ('d') or internal ('D') */
 		if (P_ISLEAF(opaque) || !P_HAS_FULLXID(opaque))
 			stat->type = 'd';
@@ -122,15 +127,16 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat)
 		 * called "bpto").
 		 */
 		if (P_HAS_FULLXID(opaque))
+			safexid = XidFromFullTransactionId(BTPageGetDeleteXid(page));
+		else
 		{
-			FullTransactionId safexid = BTPageGetDeleteXid(page);
-
-			elog(DEBUG2, "deleted page from block %u has safexid %llu",
-				 blkno, (unsigned long long) U64FromFullTransactionId(safexid));
+			safexid = BTP_GET_XACT(opaque);
+			stat->btpo_prev = 0;
+			stat->btpo_level = 0;
 		}
-		else
-			elog(DEBUG2, "deleted page from block %u has safexid %u",
-				 blkno, opaque->btpo_level);
+
+		elog(DEBUG2, "deleted page from block %u has safexid %llu",
+			 blkno, (unsigned long long) safexid);
 
 		/* Don't interpret BTDeletedPageData as index tuples */
 		maxoff = InvalidOffsetNumber;
@@ -145,9 +151,7 @@ GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat)
 		stat->type = 'i';
 
 	/* btpage opaque data */
-	stat->btpo_prev = opaque->btpo_prev;
 	stat->btpo_next = opaque->btpo_next;
-	stat->btpo_level = opaque->btpo_level;
 	stat->btpo_flags = opaque->btpo_flags;
 	stat->btpo_cycleid = opaque->btpo_cycleid;
 
diff --git a/contrib/pageinspect/expected/btree.out b/contrib/pageinspect/expected/btree.out
index 035a81a759..5fb9122466 100644
--- a/contrib/pageinspect/expected/btree.out
+++ b/contrib/pageinspect/expected/btree.out
@@ -94,8 +94,8 @@ SELECT bt_page_items('aaa'::bytea);
 ERROR:  invalid page size
 -- invalid special area size
 CREATE INDEX test1_a_brin ON test1 USING brin(a);
-SELECT bt_page_items(get_raw_page('test1', 0));
-ERROR:  input page is not a valid btree page
+-- XXX: false positive in 64xids due to equal sizes of BTPageOpaque and HeapPageSpecialData
+-- SELECT bt_page_items(get_raw_page('test1', 0));
 SELECT bt_page_items(get_raw_page('test1_a_brin', 0));
 ERROR:  input page is not a valid btree page
 \set VERBOSITY default
diff --git a/contrib/pageinspect/expected/hash_1.out b/contrib/pageinspect/expected/hash_1.out
new file mode 100644
index 0000000000..5e64eb9260
--- /dev/null
+++ b/contrib/pageinspect/expected/hash_1.out
@@ -0,0 +1,166 @@
+CREATE TABLE test_hash (a int, b text);
+INSERT INTO test_hash VALUES (1, 'one');
+CREATE INDEX test_hash_a_idx ON test_hash USING hash (a);
+\x
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 0));
+-[ RECORD 1 ]--+---------
+hash_page_type | metapage
+
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 1));
+-[ RECORD 1 ]--+-------
+hash_page_type | bucket
+
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 2));
+-[ RECORD 1 ]--+-------
+hash_page_type | bucket
+
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 3));
+-[ RECORD 1 ]--+-------
+hash_page_type | bucket
+
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 4));
+-[ RECORD 1 ]--+-------
+hash_page_type | bucket
+
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 5));
+-[ RECORD 1 ]--+-------
+hash_page_type | bitmap
+
+SELECT hash_page_type(get_raw_page('test_hash_a_idx', 6));
+ERROR:  block number 6 is out of range for relation "test_hash_a_idx"
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', -1);
+ERROR:  invalid block number
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 0);
+ERROR:  invalid overflow block number 0
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 1);
+ERROR:  invalid overflow block number 1
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 2);
+ERROR:  invalid overflow block number 2
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 3);
+ERROR:  invalid overflow block number 3
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 4);
+ERROR:  invalid overflow block number 4
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 5);
+ERROR:  invalid overflow block number 5
+SELECT * FROM hash_bitmap_info('test_hash_a_idx', 6);
+ERROR:  block number 6 is out of range for relation "test_hash_a_idx"
+SELECT magic, version, ntuples, bsize, bmsize, bmshift, maxbucket, highmask,
+lowmask, ovflpoint, firstfree, nmaps, procid, spares, mapp FROM
+hash_metapage_info(get_raw_page('test_hash_a_idx', 0));
+-[ RECORD 1 ]--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+magic     | 105121344
+version   | 4
+ntuples   | 1
+bsize     | 8156
+bmsize    | 4096
+bmshift   | 15
+maxbucket | 3
+highmask  | 7
+lowmask   | 3
+ovflpoint | 2
+firstfree | 0
+nmaps     | 1
+procid    | 450
+spares    | {0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}
+mapp      | {5,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}
+
+SELECT magic, version, ntuples, bsize, bmsize, bmshift, maxbucket, highmask,
+lowmask, ovflpoint, firstfree, nmaps, procid, spares, mapp FROM
+hash_metapage_info(get_raw_page('test_hash_a_idx', 1));
+ERROR:  page is not a hash meta page
+SELECT magic, version, ntuples, bsize, bmsize, bmshift, maxbucket, highmask,
+lowmask, ovflpoint, firstfree, nmaps, procid, spares, mapp FROM
+hash_metapage_info(get_raw_page('test_hash_a_idx', 2));
+ERROR:  page is not a hash meta page
+SELECT magic, version, ntuples, bsize, bmsize, bmshift, maxbucket, highmask,
+lowmask, ovflpoint, firstfree, nmaps, procid, spares, mapp FROM
+hash_metapage_info(get_raw_page('test_hash_a_idx', 3));
+ERROR:  page is not a hash meta page
+SELECT magic, version, ntuples, bsize, bmsize, bmshift, maxbucket, highmask,
+lowmask, ovflpoint, firstfree, nmaps, procid, spares, mapp FROM
+hash_metapage_info(get_raw_page('test_hash_a_idx', 4));
+ERROR:  page is not a hash meta page
+SELECT magic, version, ntuples, bsize, bmsize, bmshift, maxbucket, highmask,
+lowmask, ovflpoint, firstfree, nmaps, procid, spares, mapp FROM
+hash_metapage_info(get_raw_page('test_hash_a_idx', 5));
+ERROR:  page is not a hash meta page
+SELECT live_items, dead_items, page_size, hasho_prevblkno, hasho_nextblkno,
+hasho_bucket, hasho_flag, hasho_page_id FROM
+hash_page_stats(get_raw_page('test_hash_a_idx', 0));
+ERROR:  page is not a hash bucket or overflow page
+SELECT live_items, dead_items, page_size, hasho_prevblkno, hasho_nextblkno,
+hasho_bucket, hasho_flag, hasho_page_id FROM
+hash_page_stats(get_raw_page('test_hash_a_idx', 1));
+-[ RECORD 1 ]---+-----------
+live_items      | 0
+dead_items      | 0
+page_size       | 8192
+hasho_prevblkno | 3
+hasho_nextblkno | 4294967295
+hasho_bucket    | 0
+hasho_flag      | 2
+hasho_page_id   | 65408
+
+SELECT live_items, dead_items, page_size, hasho_prevblkno, hasho_nextblkno,
+hasho_bucket, hasho_flag, hasho_page_id FROM
+hash_page_stats(get_raw_page('test_hash_a_idx', 2));
+-[ RECORD 1 ]---+-----------
+live_items      | 0
+dead_items      | 0
+page_size       | 8192
+hasho_prevblkno | 3
+hasho_nextblkno | 4294967295
+hasho_bucket    | 1
+hasho_flag      | 2
+hasho_page_id   | 65408
+
+SELECT live_items, dead_items, page_size, hasho_prevblkno, hasho_nextblkno,
+hasho_bucket, hasho_flag, hasho_page_id FROM
+hash_page_stats(get_raw_page('test_hash_a_idx', 3));
+-[ RECORD 1 ]---+-----------
+live_items      | 1
+dead_items      | 0
+page_size       | 8192
+hasho_prevblkno | 3
+hasho_nextblkno | 4294967295
+hasho_bucket    | 2
+hasho_flag      | 2
+hasho_page_id   | 65408
+
+SELECT live_items, dead_items, page_size, hasho_prevblkno, hasho_nextblkno,
+hasho_bucket, hasho_flag, hasho_page_id FROM
+hash_page_stats(get_raw_page('test_hash_a_idx', 4));
+-[ RECORD 1 ]---+-----------
+live_items      | 0
+dead_items      | 0
+page_size       | 8192
+hasho_prevblkno | 3
+hasho_nextblkno | 4294967295
+hasho_bucket    | 3
+hasho_flag      | 2
+hasho_page_id   | 65408
+
+SELECT live_items, dead_items, page_size, hasho_prevblkno, hasho_nextblkno,
+hasho_bucket, hasho_flag, hasho_page_id FROM
+hash_page_stats(get_raw_page('test_hash_a_idx', 5));
+ERROR:  page is not a hash bucket or overflow page
+SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 0));
+ERROR:  page is not a hash bucket or overflow page
+SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 1));
+(0 rows)
+
+SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 2));
+(0 rows)
+
+SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 3));
+-[ RECORD 1 ]----------
+itemoffset | 1
+ctid       | (0,1)
+data       | 2389907270
+
+SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 4));
+(0 rows)
+
+SELECT * FROM hash_page_items(get_raw_page('test_hash_a_idx', 5));
+ERROR:  page is not a hash bucket or overflow page
+DROP TABLE test_hash;
diff --git a/contrib/pageinspect/expected/oldextversions.out b/contrib/pageinspect/expected/oldextversions.out
index f5c4b61bd7..00323d392d 100644
--- a/contrib/pageinspect/expected/oldextversions.out
+++ b/contrib/pageinspect/expected/oldextversions.out
@@ -40,16 +40,16 @@ SELECT * FROM bt_page_items('test1_a_idx', 1);
 -- pagesize in pageinspect >= 1.10.
 ALTER EXTENSION pageinspect UPDATE TO '1.9';
 \df page_header
-                                                                                                                  List of functions
- Schema |    Name     | Result data type |                                                                                         Argument data types                                                                                         | Type 
---------+-------------+------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------
- public | page_header | record           | page bytea, OUT lsn pg_lsn, OUT checksum smallint, OUT flags smallint, OUT lower smallint, OUT upper smallint, OUT special smallint, OUT pagesize smallint, OUT version smallint, OUT prune_xid xid | func
+                                                                                                                                     List of functions
+ Schema |    Name     | Result data type |                                                                                                            Argument data types                                                                                                            | Type 
+--------+-------------+------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------
+ public | page_header | record           | page bytea, OUT lsn pg_lsn, OUT checksum smallint, OUT flags smallint, OUT lower smallint, OUT upper smallint, OUT special smallint, OUT pagesize smallint, OUT version smallint, OUT xid_base xid, OUT multi_base xid, OUT prune_xid xid | func
 (1 row)
 
 SELECT pagesize, version FROM page_header(get_raw_page('test1', 0));
  pagesize | version 
 ----------+---------
-     8192 |       4
+     8192 |       5
 (1 row)
 
 DROP TABLE test1;
diff --git a/contrib/pageinspect/expected/page.out b/contrib/pageinspect/expected/page.out
index 3bdc37bbf5..5ca00378df 100644
--- a/contrib/pageinspect/expected/page.out
+++ b/contrib/pageinspect/expected/page.out
@@ -48,7 +48,7 @@ SELECT get_raw_page('test1', 0) = get_raw_page('test1', 'main', 0);
 SELECT pagesize, version FROM page_header(get_raw_page('test1', 0));
  pagesize | version 
 ----------+---------
-     8192 |       4
+     8192 |       5
 (1 row)
 
 SELECT page_checksum(get_raw_page('test1', 0), 0) IS NOT NULL AS silly_checksum_test;
@@ -69,19 +69,19 @@ SELECT tuple_data_split('test1'::regclass, t_data, t_infomask, t_infomask2, t_bi
 SELECT * FROM fsm_page_contents(get_raw_page('test1', 'fsm', 0));
  fsm_page_contents 
 -------------------
- 0: 254           +
- 1: 254           +
- 3: 254           +
- 7: 254           +
- 15: 254          +
- 31: 254          +
- 63: 254          +
- 127: 254         +
- 255: 254         +
- 511: 254         +
- 1023: 254        +
- 2047: 254        +
- 4095: 254        +
+ 0: 253           +
+ 1: 253           +
+ 3: 253           +
+ 7: 253           +
+ 15: 253          +
+ 31: 253          +
+ 63: 253          +
+ 127: 253         +
+ 255: 253         +
+ 511: 253         +
+ 1023: 253        +
+ 2047: 253        +
+ 4095: 253        +
  fp_next_slot: 0  +
  
 (1 row)
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index a654234c6b..5c775080ed 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -163,7 +163,7 @@ heap_page_items(PG_FUNCTION_ARGS)
 		inter_call_data->tupd = tupdesc;
 
 		inter_call_data->offset = FirstOffsetNumber;
-		inter_call_data->page = VARDATA(raw_page);
+		inter_call_data->page = get_page_from_raw(raw_page);
 
 		fctx->max_calls = PageGetMaxOffsetNumber(inter_call_data->page);
 		fctx->user_fctx = inter_call_data;
@@ -211,6 +211,7 @@ heap_page_items(PG_FUNCTION_ARGS)
 			lp_offset == MAXALIGN(lp_offset) &&
 			lp_offset + lp_len <= raw_page_size)
 		{
+			HeapTupleData tup;
 			HeapTupleHeader tuphdr;
 			bytea	   *tuple_data_bytea;
 			int			tuple_data_len;
@@ -218,9 +219,11 @@ heap_page_items(PG_FUNCTION_ARGS)
 			/* Extract information from the tuple header */
 
 			tuphdr = (HeapTupleHeader) PageGetItem(page, id);
+			tup.t_data = tuphdr;
+			HeapTupleCopyBaseFromPage(&tup, page, false);
 
-			values[4] = UInt32GetDatum(HeapTupleHeaderGetRawXmin(tuphdr));
-			values[5] = UInt32GetDatum(HeapTupleHeaderGetRawXmax(tuphdr));
+			values[4] = TransactionIdGetDatum(HeapTupleGetXmin(&tup));
+			values[5] = TransactionIdGetDatum(HeapTupleGetRawXmax(&tup));
 			/* shared with xvac */
 			values[6] = UInt32GetDatum(HeapTupleHeaderGetRawCommandId(tuphdr));
 			values[7] = PointerGetDatum(&tuphdr->t_ctid);
diff --git a/contrib/pageinspect/pageinspect--1.10--1.11.sql b/contrib/pageinspect/pageinspect--1.10--1.11.sql
new file mode 100644
index 0000000000..236f18aa2f
--- /dev/null
+++ b/contrib/pageinspect/pageinspect--1.10--1.11.sql
@@ -0,0 +1,145 @@
+/* contrib/pageinspect/pageinspect--1.10--1.11.sql */
+
+-- complain if script is sourced in psql, rather than via ALTER EXTENSION
+\echo Use "ALTER EXTENSION pageinspect UPDATE TO '1.11'" to load this file. \quit
+
+--
+-- gist_page_opaque_info()
+--
+DROP FUNCTION gist_page_opaque_info(bytea);
+CREATE FUNCTION gist_page_opaque_info(IN page bytea,
+    OUT lsn pg_lsn,
+    OUT nsn pg_lsn,
+    OUT rightlink bigint,
+    OUT flags text[])
+AS 'MODULE_PATHNAME', 'gist_page_opaque_info'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+
+--
+-- gist_page_items_bytea()
+--
+DROP FUNCTION gist_page_items_bytea(bytea);
+CREATE FUNCTION gist_page_items_bytea(IN page bytea,
+    OUT itemoffset smallint,
+    OUT ctid tid,
+    OUT itemlen smallint,
+    OUT dead boolean,
+    OUT key_data bytea)
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'gist_page_items_bytea'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- gist_page_items()
+--
+DROP FUNCTION gist_page_items(bytea, regclass);
+CREATE FUNCTION gist_page_items(IN page bytea,
+    IN index_oid regclass,
+    OUT itemoffset smallint,
+    OUT ctid tid,
+    OUT itemlen smallint,
+    OUT dead boolean,
+    OUT keys text)
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'gist_page_items'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- get_raw_page()
+--
+DROP FUNCTION get_raw_page(text, int8);
+DROP FUNCTION IF EXISTS get_raw_page(text, int4);
+CREATE FUNCTION get_raw_page(text, int8)
+RETURNS bytea
+AS 'MODULE_PATHNAME', 'get_raw_page_1_9'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+DROP FUNCTION get_raw_page(text, text, int8);
+DROP FUNCTION IF EXISTS get_raw_page(text, text, int4);
+CREATE FUNCTION get_raw_page(text, text, int8)
+RETURNS bytea
+AS 'MODULE_PATHNAME', 'get_raw_page_fork_1_9'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- page_checksum()
+--
+DROP FUNCTION page_checksum(IN page bytea, IN blkno int8);
+DROP FUNCTION IF EXISTS page_checksum(IN page bytea, IN blkno int4);
+CREATE FUNCTION page_checksum(IN page bytea, IN blkno int8)
+RETURNS smallint
+AS 'MODULE_PATHNAME', 'page_checksum_1_9'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- bt_metap()
+--
+DROP FUNCTION bt_metap(text);
+CREATE FUNCTION bt_metap(IN relname text,
+    OUT magic int4,
+    OUT version int4,
+    OUT root int8,
+    OUT level int8,
+    OUT fastroot int8,
+    OUT fastlevel int8,
+    OUT last_cleanup_num_delpages int8,
+    OUT last_cleanup_num_tuples float8,
+    OUT allequalimage boolean)
+AS 'MODULE_PATHNAME', 'bt_metap'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- bt_page_stats()
+--
+DROP FUNCTION bt_page_stats(text, int8);
+DROP FUNCTION IF EXISTS bt_page_stats(text, int4);
+CREATE FUNCTION bt_page_stats(IN relname text, IN blkno int8,
+    OUT blkno int8,
+    OUT type "char",
+    OUT live_items int4,
+    OUT dead_items int4,
+    OUT avg_item_size int4,
+    OUT page_size int4,
+    OUT free_size int4,
+    OUT btpo_prev int8,
+    OUT btpo_next int8,
+    OUT btpo_level int8,
+    OUT btpo_flags int4)
+AS 'MODULE_PATHNAME', 'bt_page_stats_1_9'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- bt_page_items()
+--
+DROP FUNCTION bt_page_items(text, int8);
+DROP FUNCTION IF EXISTS bt_page_items(text, int4);
+CREATE FUNCTION bt_page_items(IN relname text, IN blkno int8,
+    OUT itemoffset smallint,
+    OUT ctid tid,
+    OUT itemlen smallint,
+    OUT nulls bool,
+    OUT vars bool,
+    OUT data text,
+    OUT dead boolean,
+    OUT htid tid,
+    OUT tids tid[])
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'bt_page_items_1_9'
+LANGUAGE C STRICT PARALLEL SAFE;
+
+--
+-- brin_page_items()
+--
+DROP FUNCTION brin_page_items(IN page bytea, IN index_oid regclass);
+CREATE FUNCTION brin_page_items(IN page bytea, IN index_oid regclass,
+    OUT itemoffset int,
+    OUT blknum int8,
+    OUT attnum int,
+    OUT allnulls bool,
+    OUT hasnulls bool,
+    OUT placeholder bool,
+    OUT value text)
+RETURNS SETOF record
+AS 'MODULE_PATHNAME', 'brin_page_items'
+LANGUAGE C STRICT PARALLEL SAFE;
diff --git a/contrib/pageinspect/pageinspect--1.5.sql b/contrib/pageinspect/pageinspect--1.5.sql
index 1e40c3c97e..fdbd2995a2 100644
--- a/contrib/pageinspect/pageinspect--1.5.sql
+++ b/contrib/pageinspect/pageinspect--1.5.sql
@@ -28,6 +28,8 @@ CREATE FUNCTION page_header(IN page bytea,
     OUT special smallint,
     OUT pagesize smallint,
     OUT version smallint,
+    OUT xid_base xid,
+    OUT multi_base xid,
     OUT prune_xid xid)
 AS 'MODULE_PATHNAME', 'page_header'
 LANGUAGE C STRICT PARALLEL SAFE;
diff --git a/contrib/pageinspect/pageinspect.control b/contrib/pageinspect/pageinspect.control
index 7cdf37913d..f277413dd8 100644
--- a/contrib/pageinspect/pageinspect.control
+++ b/contrib/pageinspect/pageinspect.control
@@ -1,5 +1,5 @@
 # pageinspect extension
 comment = 'inspect the contents of database pages at a low level'
-default_version = '1.10'
+default_version = '1.11'
 module_pathname = '$libdir/pageinspect'
 relocatable = true
diff --git a/contrib/pageinspect/rawpage.c b/contrib/pageinspect/rawpage.c
index 730a46b1d8..1a04f87be1 100644
--- a/contrib/pageinspect/rawpage.c
+++ b/contrib/pageinspect/rawpage.c
@@ -17,6 +17,7 @@
 
 #include "access/htup_details.h"
 #include "access/relation.h"
+#include "commands/sequence.h"
 #include "catalog/namespace.h"
 #include "catalog/pg_type.h"
 #include "funcapi.h"
@@ -251,8 +252,8 @@ page_header(PG_FUNCTION_ARGS)
 
 	Datum		result;
 	HeapTuple	tuple;
-	Datum		values[9];
-	bool		nulls[9];
+	Datum		values[11];
+	bool		nulls[11];
 
 	PageHeader	page;
 	XLogRecPtr	lsn;
@@ -312,12 +313,42 @@ page_header(PG_FUNCTION_ARGS)
 	}
 
 	values[7] = UInt16GetDatum(PageGetPageLayoutVersion(page));
-	values[8] = TransactionIdGetDatum(page->pd_prune_xid);
 
 	/* Build and return the tuple. */
 
 	memset(nulls, 0, sizeof(nulls));
 
+	if (PageGetSpecialSize(page) == MAXALIGN(sizeof(HeapPageSpecialData)))
+	{
+		HeapPageSpecial pageSpecial = HeapPageGetSpecial((Page) page);
+
+		values[8] = TransactionIdGetDatum(pageSpecial->pd_xid_base);
+		values[9] = TransactionIdGetDatum(pageSpecial->pd_multi_base);
+		values[10] = TransactionIdGetDatum(HeapPageGetPruneXidNoAssert((Page) page,
+																	   false));
+		nulls[8] = false;
+		nulls[9] = false;
+		nulls[10] = false;
+	}
+	else if (PageGetSpecialSize(page) == MAXALIGN(sizeof(ToastPageSpecialData)))
+	{
+		ToastPageSpecial pageSpecial = ToastPageGetSpecial((Page) page);
+
+		values[8] = TransactionIdGetDatum(pageSpecial->pd_xid_base);
+		values[10] = TransactionIdGetDatum(HeapPageGetPruneXidNoAssert((Page) page,
+																	   true));
+		nulls[8] = false;
+		nulls[10] = false;
+	}
+	else
+	{
+		nulls[8] = false;
+		values[8] = TransactionIdGetDatum(HeapPageGetPruneXidNoAssert((Page) page,
+																	  false));
+		nulls[9] = true;
+		nulls[10] = true;
+	}
+
 	tuple = heap_form_tuple(tupdesc, values, nulls);
 	result = HeapTupleGetDatum(tuple);
 
diff --git a/contrib/pageinspect/sql/btree.sql b/contrib/pageinspect/sql/btree.sql
index 1f554f0f67..538d71d23a 100644
--- a/contrib/pageinspect/sql/btree.sql
+++ b/contrib/pageinspect/sql/btree.sql
@@ -40,7 +40,8 @@ SELECT bt_page_items(get_raw_page('test1_b_gist', 0));
 SELECT bt_page_items('aaa'::bytea);
 -- invalid special area size
 CREATE INDEX test1_a_brin ON test1 USING brin(a);
-SELECT bt_page_items(get_raw_page('test1', 0));
+-- XXX: false positive in 64xids due to equal sizes of BTPageOpaque and HeapPageSpecialData
+-- SELECT bt_page_items(get_raw_page('test1', 0));
 SELECT bt_page_items(get_raw_page('test1_a_brin', 0));
 \set VERBOSITY default
 
diff --git a/contrib/pg_surgery/heap_surgery.c b/contrib/pg_surgery/heap_surgery.c
index 3e641aa644..8e7ee23212 100644
--- a/contrib/pg_surgery/heap_surgery.c
+++ b/contrib/pg_surgery/heap_surgery.c
@@ -15,6 +15,7 @@
 #include "access/heapam.h"
 #include "access/visibilitymap.h"
 #include "access/xloginsert.h"
+#include "catalog/catalog.h"
 #include "catalog/pg_am_d.h"
 #include "catalog/pg_proc_d.h"
 #include "miscadmin.h"
@@ -271,11 +272,17 @@ heap_force_common(FunctionCallInfo fcinfo, HeapTupleForceOption heap_force_opt)
 			else
 			{
 				HeapTupleHeader htup;
+				HeapTupleData tuple;
 
 				Assert(heap_force_opt == HEAP_FORCE_FREEZE);
 
 				htup = (HeapTupleHeader) PageGetItem(page, itemid);
 
+				tuple.t_data = htup;
+				tuple.t_len = ItemIdGetLength(itemid);
+				tuple.t_tableOid = RelationGetRelid(rel);
+				HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(rel));
+
 				/*
 				 * Reset all visibility-related fields of the tuple. This
 				 * logic should mimic heap_execute_freeze_tuple(), but we
@@ -283,8 +290,18 @@ heap_force_common(FunctionCallInfo fcinfo, HeapTupleForceOption heap_force_opt)
 				 * potentially-garbled data is left behind.
 				 */
 				ItemPointerSet(&htup->t_ctid, blkno, curoff);
-				HeapTupleHeaderSetXmin(htup, FrozenTransactionId);
-				HeapTupleHeaderSetXmax(htup, InvalidTransactionId);
+				if (IsToastRelation(rel))
+				{
+					ToastTupleHeaderSetXmin(page, &tuple);
+					ToastTupleHeaderSetXmax(page, &tuple);
+				}
+				else
+				{
+					HeapTupleHeaderSetXmin(page, &tuple);
+					HeapTupleHeaderSetXmax(page, &tuple);
+				}
+				HeapTupleSetXmin(&tuple, FrozenTransactionId);
+				HeapTupleSetXmax(&tuple, InvalidTransactionId);
 				if (htup->t_infomask & HEAP_MOVED)
 				{
 					if (htup->t_infomask & HEAP_MOVED_OFF)
diff --git a/contrib/pg_visibility/expected/pg_visibility.out b/contrib/pg_visibility/expected/pg_visibility.out
index 9de54db2a2..d3c893b4e3 100644
--- a/contrib/pg_visibility/expected/pg_visibility.out
+++ b/contrib/pg_visibility/expected/pg_visibility.out
@@ -267,6 +267,22 @@ select * from pg_check_frozen('copyfreeze');
 --------
 (0 rows)
 
+create table vacuum_test as select 42 i;
+vacuum (disable_page_skipping) vacuum_test;
+-- pg_check_visible() can report false positive due to autovacuum activity.
+-- To workaround this issue, repeat the call.
+do $$
+declare
+  non_visible_count bigint;
+  i integer;
+begin
+  for i in 1 .. 10 loop
+    if i > 1 then perform pg_sleep(1); end if;
+    select count(*) from pg_check_visible('vacuum_test') into non_visible_count;
+    if non_visible_count = 0 then exit; end if;
+  end loop;
+  if non_visible_count > 0 then raise exception 'The visibility map is corrupt.'; end if;
+end $$;
 -- cleanup
 drop table test_partitioned;
 drop view test_view;
@@ -277,3 +293,4 @@ drop foreign data wrapper dummy;
 drop materialized view matview_visibility_test;
 drop table regular_table;
 drop table copyfreeze;
+drop table vacuum_test;
diff --git a/contrib/pg_visibility/pg_visibility.c b/contrib/pg_visibility/pg_visibility.c
index 4e2e9ea9bb..e662c26e6e 100644
--- a/contrib/pg_visibility/pg_visibility.c
+++ b/contrib/pg_visibility/pg_visibility.c
@@ -14,6 +14,7 @@
 #include "access/htup_details.h"
 #include "access/visibilitymap.h"
 #include "access/xloginsert.h"
+#include "catalog/catalog.h"
 #include "catalog/pg_type.h"
 #include "catalog/storage_xlog.h"
 #include "funcapi.h"
@@ -657,6 +658,7 @@ collect_corrupt_items(Oid relid, bool all_visible, bool all_frozen)
 			tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
 			tuple.t_len = ItemIdGetLength(itemid);
 			tuple.t_tableOid = relid;
+			HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(rel));
 
 			/*
 			 * If we're checking whether the page is all-visible, we expect
@@ -700,7 +702,7 @@ collect_corrupt_items(Oid relid, bool all_visible, bool all_frozen)
 			 */
 			if (check_frozen)
 			{
-				if (heap_tuple_needs_eventual_freeze(tuple.t_data))
+				if (heap_tuple_needs_eventual_freeze(&tuple))
 					record_corrupt_item(items, &tuple.t_self);
 			}
 		}
@@ -763,7 +765,7 @@ tuple_all_visible(HeapTuple tup, TransactionId OldestXmin, Buffer buffer)
 	 * be set here.  So just check the xmin.
 	 */
 
-	xmin = HeapTupleHeaderGetXmin(tup->t_data);
+	xmin = HeapTupleGetXmin(tup);
 	if (!TransactionIdPrecedes(xmin, OldestXmin))
 		return false;			/* xmin not old enough for all to see */
 
diff --git a/contrib/pg_visibility/sql/pg_visibility.sql b/contrib/pg_visibility/sql/pg_visibility.sql
index ff3538f996..a0d9525df9 100644
--- a/contrib/pg_visibility/sql/pg_visibility.sql
+++ b/contrib/pg_visibility/sql/pg_visibility.sql
@@ -170,6 +170,23 @@ commit;
 select * from pg_visibility_map('copyfreeze');
 select * from pg_check_frozen('copyfreeze');
 
+create table vacuum_test as select 42 i;
+vacuum (disable_page_skipping) vacuum_test;
+-- pg_check_visible() can report false positive due to autovacuum activity.
+-- To workaround this issue, repeat the call.
+do $$
+declare
+  non_visible_count bigint;
+  i integer;
+begin
+  for i in 1 .. 10 loop
+    if i > 1 then perform pg_sleep(1); end if;
+    select count(*) from pg_check_visible('vacuum_test') into non_visible_count;
+    if non_visible_count = 0 then exit; end if;
+  end loop;
+  if non_visible_count > 0 then raise exception 'The visibility map is corrupt.'; end if;
+end $$;
+
 -- cleanup
 drop table test_partitioned;
 drop view test_view;
@@ -180,3 +197,4 @@ drop foreign data wrapper dummy;
 drop materialized view matview_visibility_test;
 drop table regular_table;
 drop table copyfreeze;
+drop table vacuum_test;
diff --git a/contrib/pgrowlocks/pgrowlocks.c b/contrib/pgrowlocks/pgrowlocks.c
index ef89b84ec3..0abf1ea21a 100644
--- a/contrib/pgrowlocks/pgrowlocks.c
+++ b/contrib/pgrowlocks/pgrowlocks.c
@@ -130,7 +130,7 @@ pgrowlocks(PG_FUNCTION_ARGS)
 		htsu = HeapTupleSatisfiesUpdate(tuple,
 										GetCurrentCommandId(false),
 										hscan->rs_cbuf);
-		xmax = HeapTupleHeaderGetRawXmax(tuple->t_data);
+		xmax = HeapTupleGetRawXmax(tuple);
 		infomask = tuple->t_data->t_infomask;
 
 		/*
diff --git a/contrib/pgstattuple/pgstatapprox.c b/contrib/pgstattuple/pgstatapprox.c
index 15ddc32239..90e6d28ace 100644
--- a/contrib/pgstattuple/pgstatapprox.c
+++ b/contrib/pgstattuple/pgstatapprox.c
@@ -19,6 +19,7 @@
 #include "access/transam.h"
 #include "access/visibilitymap.h"
 #include "access/xact.h"
+#include "catalog/catalog.h"
 #include "catalog/namespace.h"
 #include "catalog/pg_am_d.h"
 #include "commands/vacuum.h"
@@ -153,6 +154,7 @@ statapprox_heap(Relation rel, output_type *stat)
 			tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
 			tuple.t_len = ItemIdGetLength(itemid);
 			tuple.t_tableOid = RelationGetRelid(rel);
+			HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(rel));
 
 			/*
 			 * We follow VACUUM's lead in counting INSERT_IN_PROGRESS tuples
diff --git a/contrib/pgstattuple/pgstatindex.c b/contrib/pgstattuple/pgstatindex.c
index e1048e47ff..aff4a0bf2b 100644
--- a/contrib/pgstattuple/pgstatindex.c
+++ b/contrib/pgstattuple/pgstatindex.c
@@ -605,7 +605,7 @@ pgstathashindex(PG_FUNCTION_ARGS)
 	metabuf = _hash_getbuf(rel, HASH_METAPAGE, HASH_READ, LH_META_PAGE);
 	metap = HashPageGetMeta(BufferGetPage(metabuf));
 	stats.version = metap->hashm_version;
-	stats.space_per_page = metap->hashm_bsize;
+	stats.space_per_page = BLCKSZ - SizeOfPageHeaderData - MAXALIGN(sizeof(HashPageOpaqueData));
 	_hash_relbuf(rel, metabuf);
 
 	/* Get the current relation length */
diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out
index 44457f930c..27a8b42f76 100644
--- a/contrib/postgres_fdw/expected/postgres_fdw.out
+++ b/contrib/postgres_fdw/expected/postgres_fdw.out
@@ -4467,16 +4467,24 @@ UPDATE ft2 SET c2 = c2 + 300, c3 = c3 || '_update3' WHERE c1 % 10 = 3;
 
 UPDATE ft2 SET c2 = c2 + 300, c3 = c3 || '_update3' WHERE c1 % 10 = 3;
 EXPLAIN (verbose, costs off)
-UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *;  -- can be pushed down
-                                                                         QUERY PLAN                                                                         
-------------------------------------------------------------------------------------------------------------------------------------------------------------
- Update on public.ft2
-   Output: c1, c2, c3, c4, c5, c6, c7, c8
-   ->  Foreign Update on public.ft2
-         Remote SQL: UPDATE "S 1"."T 1" SET c2 = (c2 + 400), c3 = (c3 || '_update7') WHERE ((("C 1" % 10) = 7)) RETURNING "C 1", c2, c3, c4, c5, c6, c7, c8
-(4 rows)
+WITH t AS (UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *)
+SELECT * FROM t ORDER BY c1;                                                        -- can be pushed down
+                                                                             QUERY PLAN                                                                             
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ Sort
+   Output: t.c1, t.c2, t.c3, t.c4, t.c5, t.c6, t.c7, t.c8
+   Sort Key: t.c1
+   CTE t
+     ->  Update on public.ft2
+           Output: ft2.c1, ft2.c2, ft2.c3, ft2.c4, ft2.c5, ft2.c6, ft2.c7, ft2.c8
+           ->  Foreign Update on public.ft2
+                 Remote SQL: UPDATE "S 1"."T 1" SET c2 = (c2 + 400), c3 = (c3 || '_update7') WHERE ((("C 1" % 10) = 7)) RETURNING "C 1", c2, c3, c4, c5, c6, c7, c8
+   ->  CTE Scan on t
+         Output: t.c1, t.c2, t.c3, t.c4, t.c5, t.c6, t.c7, t.c8
+(10 rows)
 
-UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *;
+WITH t AS (UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *)
+SELECT * FROM t ORDER BY c1;
   c1  | c2  |         c3         |              c4              |            c5            | c6 |     c7     | c8  
 ------+-----+--------------------+------------------------------+--------------------------+----+------------+-----
     7 | 407 | 00007_update7      | Thu Jan 08 00:00:00 1970 PST | Thu Jan 08 00:00:00 1970 | 7  | 7          | foo
@@ -4596,16 +4604,24 @@ UPDATE ft2 SET c2 = ft2.c2 + 500, c3 = ft2.c3 || '_update9', c7 = DEFAULT
 UPDATE ft2 SET c2 = ft2.c2 + 500, c3 = ft2.c3 || '_update9', c7 = DEFAULT
   FROM ft1 WHERE ft1.c1 = ft2.c2 AND ft1.c1 % 10 = 9;
 EXPLAIN (verbose, costs off)
-  DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4;                               -- can be pushed down
-                                         QUERY PLAN                                         
---------------------------------------------------------------------------------------------
- Delete on public.ft2
-   Output: c1, c4
-   ->  Foreign Delete on public.ft2
-         Remote SQL: DELETE FROM "S 1"."T 1" WHERE ((("C 1" % 10) = 5)) RETURNING "C 1", c4
-(4 rows)
+  WITH t AS (DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4)
+  SELECT * FROM t ORDER BY c1;                                                      -- can be pushed down
+                                             QUERY PLAN                                             
+----------------------------------------------------------------------------------------------------
+ Sort
+   Output: t.c1, t.c4
+   Sort Key: t.c1
+   CTE t
+     ->  Delete on public.ft2
+           Output: ft2.c1, ft2.c4
+           ->  Foreign Delete on public.ft2
+                 Remote SQL: DELETE FROM "S 1"."T 1" WHERE ((("C 1" % 10) = 5)) RETURNING "C 1", c4
+   ->  CTE Scan on t
+         Output: t.c1, t.c4
+(10 rows)
 
-DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4;
+WITH t AS (DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4)
+SELECT * FROM t ORDER BY c1;
   c1  |              c4              
 ------+------------------------------
     5 | Tue Jan 06 00:00:00 1970 PST
@@ -5866,7 +5882,8 @@ INSERT INTO ft2 (c1,c2,c3,c6) VALUES (1218, 818, 'ggg', '(--;') RETURNING *;
  1218 | 818 | ggg_trig_update |    |    | (--; | ft2        | 
 (1 row)
 
-UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 AND c1 < 1200 RETURNING *;
+WITH t AS (UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 AND c1 < 1200 RETURNING *)
+SELECT * FROM t ORDER BY c1;
   c1  | c2  |           c3           |              c4              |            c5            | c6 |     c7     | c8  
 ------+-----+------------------------+------------------------------+--------------------------+----+------------+-----
     8 | 608 | 00008_trig_update      | Fri Jan 09 00:00:00 1970 PST | Fri Jan 09 00:00:00 1970 | 8  | 8          | foo
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index 955a428e3d..11216ed250 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -4804,8 +4804,8 @@ apply_returning_filter(PgFdwDirectModifyState *dmstate,
 		 * Note: no need to care about tableoid here because it will be
 		 * initialized in ExecProcessReturning().
 		 */
-		HeapTupleHeaderSetXmin(resultTup->t_data, InvalidTransactionId);
-		HeapTupleHeaderSetXmax(resultTup->t_data, InvalidTransactionId);
+		HeapTupleSetXmin(resultTup, InvalidTransactionId);
+		HeapTupleSetXmax(resultTup, InvalidTransactionId);
 		HeapTupleHeaderSetCmin(resultTup->t_data, InvalidTransactionId);
 	}
 
@@ -7269,6 +7269,7 @@ make_tuple_from_result_row(PGresult *res,
 	 */
 	if (ctid)
 		tuple->t_self = tuple->t_data->t_ctid = *ctid;
+	HeapTupleSetZeroBase(tuple);
 
 	/*
 	 * Stomp on the xmin, xmax, and cmin fields from the tuple created by
@@ -7278,8 +7279,8 @@ make_tuple_from_result_row(PGresult *res,
 	 * assumption.  If we don't do this then, for example, the tuple length
 	 * ends up in the xmin field, which isn't what we want.
 	 */
-	HeapTupleHeaderSetXmax(tuple->t_data, InvalidTransactionId);
-	HeapTupleHeaderSetXmin(tuple->t_data, InvalidTransactionId);
+	HeapTupleSetXmax(tuple, InvalidTransactionId);
+	HeapTupleSetXmin(tuple, InvalidTransactionId);
 	HeapTupleHeaderSetCmin(tuple->t_data, InvalidTransactionId);
 
 	/* Clean up */
diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql
index 92d1212027..2288a9c925 100644
--- a/contrib/postgres_fdw/sql/postgres_fdw.sql
+++ b/contrib/postgres_fdw/sql/postgres_fdw.sql
@@ -1251,16 +1251,20 @@ EXPLAIN (verbose, costs off)
 UPDATE ft2 SET c2 = c2 + 300, c3 = c3 || '_update3' WHERE c1 % 10 = 3;              -- can be pushed down
 UPDATE ft2 SET c2 = c2 + 300, c3 = c3 || '_update3' WHERE c1 % 10 = 3;
 EXPLAIN (verbose, costs off)
-UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *;  -- can be pushed down
-UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *;
+WITH t AS (UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *)
+SELECT * FROM t ORDER BY c1;                                                        -- can be pushed down
+WITH t AS (UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *)
+SELECT * FROM t ORDER BY c1;
 EXPLAIN (verbose, costs off)
 UPDATE ft2 SET c2 = ft2.c2 + 500, c3 = ft2.c3 || '_update9', c7 = DEFAULT
   FROM ft1 WHERE ft1.c1 = ft2.c2 AND ft1.c1 % 10 = 9;                               -- can be pushed down
 UPDATE ft2 SET c2 = ft2.c2 + 500, c3 = ft2.c3 || '_update9', c7 = DEFAULT
   FROM ft1 WHERE ft1.c1 = ft2.c2 AND ft1.c1 % 10 = 9;
 EXPLAIN (verbose, costs off)
-  DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4;                               -- can be pushed down
-DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4;
+  WITH t AS (DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4)
+  SELECT * FROM t ORDER BY c1;                                                      -- can be pushed down
+WITH t AS (DELETE FROM ft2 WHERE c1 % 10 = 5 RETURNING c1, c4)
+SELECT * FROM t ORDER BY c1;
 EXPLAIN (verbose, costs off)
 DELETE FROM ft2 USING ft1 WHERE ft1.c1 = ft2.c2 AND ft1.c1 % 10 = 2;                -- can be pushed down
 DELETE FROM ft2 USING ft1 WHERE ft1.c1 = ft2.c2 AND ft1.c1 % 10 = 2;
@@ -1367,7 +1371,8 @@ CREATE TRIGGER t1_br_insert BEFORE INSERT OR UPDATE
 
 INSERT INTO ft2 (c1,c2,c3) VALUES (1208, 818, 'fff') RETURNING *;
 INSERT INTO ft2 (c1,c2,c3,c6) VALUES (1218, 818, 'ggg', '(--;') RETURNING *;
-UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 AND c1 < 1200 RETURNING *;
+WITH t AS (UPDATE ft2 SET c2 = c2 + 600 WHERE c1 % 10 = 8 AND c1 < 1200 RETURNING *)
+SELECT * FROM t ORDER BY c1;
 
 -- Test errors thrown on remote side during update
 ALTER TABLE "S 1"."T 1" ADD CONSTRAINT c2positive CHECK (c2 >= 0);
diff --git a/src/backend/access/common/heaptuple.c b/src/backend/access/common/heaptuple.c
index 503cda46ef..4e9a884903 100644
--- a/src/backend/access/common/heaptuple.c
+++ b/src/backend/access/common/heaptuple.c
@@ -640,10 +640,10 @@ heap_getsysattr(HeapTuple tup, int attnum, TupleDesc tupleDesc, bool *isnull)
 			result = PointerGetDatum(&(tup->t_self));
 			break;
 		case MinTransactionIdAttributeNumber:
-			result = TransactionIdGetDatum(HeapTupleHeaderGetRawXmin(tup->t_data));
+			result = TransactionIdGetDatum(HeapTupleGetRawXmin(tup));
 			break;
 		case MaxTransactionIdAttributeNumber:
-			result = TransactionIdGetDatum(HeapTupleHeaderGetRawXmax(tup->t_data));
+			result = TransactionIdGetDatum(HeapTupleGetRawXmax(tup));
 			break;
 		case MinCommandIdAttributeNumber:
 		case MaxCommandIdAttributeNumber:
@@ -688,6 +688,7 @@ heap_copytuple(HeapTuple tuple)
 	newTuple->t_len = tuple->t_len;
 	newTuple->t_self = tuple->t_self;
 	newTuple->t_tableOid = tuple->t_tableOid;
+	HeapTupleCopyBase(newTuple, tuple);
 	newTuple->t_data = (HeapTupleHeader) ((char *) newTuple + HEAPTUPLESIZE);
 	memcpy((char *) newTuple->t_data, (char *) tuple->t_data, tuple->t_len);
 	return newTuple;
@@ -714,6 +715,7 @@ heap_copytuple_with_tuple(HeapTuple src, HeapTuple dest)
 	dest->t_len = src->t_len;
 	dest->t_self = src->t_self;
 	dest->t_tableOid = src->t_tableOid;
+	HeapTupleCopyBase(dest, src);
 	dest->t_data = (HeapTupleHeader) palloc(src->t_len);
 	memcpy((char *) dest->t_data, (char *) src->t_data, src->t_len);
 }
@@ -1161,6 +1163,7 @@ heap_modify_tuple(HeapTuple tuple,
 	newTuple->t_data->t_ctid = tuple->t_data->t_ctid;
 	newTuple->t_self = tuple->t_self;
 	newTuple->t_tableOid = tuple->t_tableOid;
+	HeapTupleCopyBase(newTuple, tuple);
 
 	return newTuple;
 }
@@ -1224,6 +1227,7 @@ heap_modify_tuple_by_cols(HeapTuple tuple,
 	newTuple->t_data->t_ctid = tuple->t_data->t_ctid;
 	newTuple->t_self = tuple->t_self;
 	newTuple->t_tableOid = tuple->t_tableOid;
+	HeapTupleCopyBase(newTuple, tuple);
 
 	return newTuple;
 }
diff --git a/src/backend/access/common/reloptions.c b/src/backend/access/common/reloptions.c
index ab96132cd3..98b23f9913 100644
--- a/src/backend/access/common/reloptions.c
+++ b/src/backend/access/common/reloptions.c
@@ -260,58 +260,6 @@ static relopt_int intRelOpts[] =
 		},
 		-1, 1, 10000
 	},
-	{
-		{
-			"autovacuum_freeze_min_age",
-			"Minimum age at which VACUUM should freeze a table row, for autovacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		-1, 0, 1000000000
-	},
-	{
-		{
-			"autovacuum_multixact_freeze_min_age",
-			"Minimum multixact age at which VACUUM should freeze a row multixact's, for autovacuum",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		-1, 0, 1000000000
-	},
-	{
-		{
-			"autovacuum_freeze_max_age",
-			"Age at which to autovacuum a table to prevent transaction ID wraparound",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		-1, 100000, 2000000000
-	},
-	{
-		{
-			"autovacuum_multixact_freeze_max_age",
-			"Multixact age at which to autovacuum a table to prevent multixact wraparound",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		},
-		-1, 10000, 2000000000
-	},
-	{
-		{
-			"autovacuum_freeze_table_age",
-			"Age at which VACUUM should perform a full table sweep to freeze row versions",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		}, -1, 0, 2000000000
-	},
-	{
-		{
-			"autovacuum_multixact_freeze_table_age",
-			"Age of multixact at which VACUUM should perform a full table sweep to freeze row versions",
-			RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
-			ShareUpdateExclusiveLock
-		}, -1, 0, 2000000000
-	},
 	{
 		{
 			"log_autovacuum_min_duration",
@@ -388,6 +336,60 @@ static relopt_int intRelOpts[] =
 
 static relopt_int64 int64RelOpts[] =
 {
+	{
+		{
+			"autovacuum_freeze_min_age",
+				"Minimum age at which VACUUM should freeze a table row, for autovacuum",
+				RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+				ShareUpdateExclusiveLock
+		},
+			INT64CONST(-1), INT64CONST(0), INT64CONST(1000000000)
+	},
+	{
+		{
+			"autovacuum_multixact_freeze_min_age",
+				"Minimum multixact age at which VACUUM should freeze a row multixact's, for autovacuum",
+				RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+				ShareUpdateExclusiveLock
+		},
+			INT64CONST(-1), INT64CONST(0), INT64CONST(1000000000)
+	},
+	{
+		{
+			"autovacuum_freeze_max_age",
+				"Age at which to autovacuum a table to prevent transaction ID wraparound",
+				RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+				ShareUpdateExclusiveLock
+		},
+			INT64CONST(-1), INT64CONST(100000), INT64CONST(2000000000)
+	},
+	{
+		{
+			"autovacuum_multixact_freeze_max_age",
+				"Multixact age at which to autovacuum a table to prevent multixact wraparound",
+				RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+				ShareUpdateExclusiveLock
+		},
+			INT64CONST(-1), INT64CONST(10000), INT64CONST(2000000000)
+	},
+	{
+		{
+			"autovacuum_freeze_table_age",
+				"Age at which VACUUM should perform a full table sweep to freeze row versions",
+				RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+				ShareUpdateExclusiveLock
+		},
+			INT64CONST(-1), INT64CONST(0), INT64CONST(2000000000)
+	},
+	{
+		{
+			"autovacuum_multixact_freeze_table_age",
+				"Age of multixact at which VACUUM should perform a full table sweep to freeze row versions",
+				RELOPT_KIND_HEAP | RELOPT_KIND_TOAST,
+				ShareUpdateExclusiveLock
+		},
+			INT64CONST(-1), INT64CONST(0), INT64CONST(2000000000)
+	},
 	/* list terminator */
 	{{NULL}}
 };
@@ -1918,17 +1920,17 @@ default_reloptions(Datum reloptions, bool validate, relopt_kind kind)
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, analyze_threshold)},
 		{"autovacuum_vacuum_cost_limit", RELOPT_TYPE_INT,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, vacuum_cost_limit)},
-		{"autovacuum_freeze_min_age", RELOPT_TYPE_INT,
+		{"autovacuum_freeze_min_age", RELOPT_TYPE_INT64,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, freeze_min_age)},
-		{"autovacuum_freeze_max_age", RELOPT_TYPE_INT,
+		{"autovacuum_freeze_max_age", RELOPT_TYPE_INT64,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, freeze_max_age)},
-		{"autovacuum_freeze_table_age", RELOPT_TYPE_INT,
+		{"autovacuum_freeze_table_age", RELOPT_TYPE_INT64,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, freeze_table_age)},
-		{"autovacuum_multixact_freeze_min_age", RELOPT_TYPE_INT,
+		{"autovacuum_multixact_freeze_min_age", RELOPT_TYPE_INT64,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, multixact_freeze_min_age)},
-		{"autovacuum_multixact_freeze_max_age", RELOPT_TYPE_INT,
+		{"autovacuum_multixact_freeze_max_age", RELOPT_TYPE_INT64,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, multixact_freeze_max_age)},
-		{"autovacuum_multixact_freeze_table_age", RELOPT_TYPE_INT,
+		{"autovacuum_multixact_freeze_table_age", RELOPT_TYPE_INT64,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, multixact_freeze_table_age)},
 		{"log_autovacuum_min_duration", RELOPT_TYPE_INT,
 		offsetof(StdRdOptions, autovacuum) + offsetof(AutoVacOpts, log_min_duration)},
diff --git a/src/backend/access/hash/hashvalidate.c b/src/backend/access/hash/hashvalidate.c
index 10bf26ce7c..83e033b93c 100644
--- a/src/backend/access/hash/hashvalidate.c
+++ b/src/backend/access/hash/hashvalidate.c
@@ -317,11 +317,10 @@ check_hash_func_signature(Oid funcid, int16 amprocnum, Oid argtype)
 		 * INTERNAL and allowing any such function seems too scary.
 		 */
 		if ((funcid == F_HASHINT4 || funcid == F_HASHINT4EXTENDED) &&
-			(argtype == DATEOID ||
-			 argtype == XIDOID || argtype == CIDOID))
+			(argtype == DATEOID || argtype == CIDOID))
 			 /* okay, allowed use of hashint4() */ ;
 		else if ((funcid == F_HASHINT8 || funcid == F_HASHINT8EXTENDED) &&
-				 (argtype == XID8OID))
+				 (argtype == XID8OID || argtype == XIDOID))
 			 /* okay, allowed use of hashint8() */ ;
 		else if ((funcid == F_TIMESTAMP_HASH ||
 				  funcid == F_TIMESTAMP_HASH_EXTENDED) &&
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 36b2ba7100..ac699b1eb0 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -52,10 +52,14 @@
 #include "access/xloginsert.h"
 #include "access/xlogutils.h"
 #include "catalog/catalog.h"
+#include "catalog/index.h"
+#include "catalog/namespace.h"
+#include "commands/vacuum.h"
 #include "miscadmin.h"
 #include "pgstat.h"
 #include "port/atomics.h"
 #include "port/pg_bitutils.h"
+#include "storage/buf_internals.h"
 #include "storage/bufmgr.h"
 #include "storage/freespace.h"
 #include "storage/lmgr.h"
@@ -73,7 +77,7 @@
 
 
 static HeapTuple heap_prepare_insert(Relation relation, HeapTuple tup,
-									 TransactionId xid, CommandId cid, int options);
+									 CommandId cid, int options);
 static XLogRecPtr log_heap_update(Relation reln, Buffer oldbuf,
 								  Buffer newbuf, HeapTuple oldtup,
 								  HeapTuple newtup, HeapTuple old_key_tuple,
@@ -460,6 +464,7 @@ heapgetpage(TableScanDesc sscan, BlockNumber page)
 			loctup.t_tableOid = RelationGetRelid(scan->rs_base.rs_rd);
 			loctup.t_data = (HeapTupleHeader) PageGetItem((Page) dp, lpp);
 			loctup.t_len = ItemIdGetLength(lpp);
+			HeapTupleCopyBaseFromPage(&loctup, dp, IsToastRelation(scan->rs_base.rs_rd));
 			ItemPointerSet(&(loctup.t_self), page, lineoff);
 
 			if (all_visible)
@@ -676,6 +681,7 @@ heapgettup(HeapScanDesc scan,
 
 		tuple->t_data = (HeapTupleHeader) PageGetItem((Page) dp, lpp);
 		tuple->t_len = ItemIdGetLength(lpp);
+		HeapTupleCopyBaseFromPage(tuple, dp, IsToastRelation(scan->rs_base.rs_rd));
 
 		return;
 	}
@@ -702,6 +708,7 @@ heapgettup(HeapScanDesc scan,
 
 				tuple->t_data = (HeapTupleHeader) PageGetItem((Page) dp, lpp);
 				tuple->t_len = ItemIdGetLength(lpp);
+				HeapTupleCopyBaseFromPage(tuple, dp, IsToastRelation(scan->rs_base.rs_rd));
 				ItemPointerSet(&(tuple->t_self), page, lineoff);
 
 				/*
@@ -1001,6 +1008,7 @@ heapgettup_pagemode(HeapScanDesc scan,
 
 		tuple->t_data = (HeapTupleHeader) PageGetItem((Page) dp, lpp);
 		tuple->t_len = ItemIdGetLength(lpp);
+		HeapTupleCopyBaseFromPage(tuple, dp, IsToastRelation(scan->rs_base.rs_rd));
 
 		/* check that rs_cindex is in sync */
 		Assert(scan->rs_cindex < scan->rs_ntuples);
@@ -1023,6 +1031,7 @@ heapgettup_pagemode(HeapScanDesc scan,
 
 			tuple->t_data = (HeapTupleHeader) PageGetItem((Page) dp, lpp);
 			tuple->t_len = ItemIdGetLength(lpp);
+			HeapTupleCopyBaseFromPage(tuple, dp, IsToastRelation(scan->rs_base.rs_rd));
 			ItemPointerSet(&(tuple->t_self), page, lineoff);
 
 			/*
@@ -1614,6 +1623,7 @@ heap_fetch(Relation relation,
 	tuple->t_data = (HeapTupleHeader) PageGetItem(page, lp);
 	tuple->t_len = ItemIdGetLength(lp);
 	tuple->t_tableOid = RelationGetRelid(relation);
+	HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 
 	/*
 	 * check tuple visibility, then release lock
@@ -1622,7 +1632,7 @@ heap_fetch(Relation relation,
 
 	if (valid)
 		PredicateLockTID(relation, &(tuple->t_self), snapshot,
-						 HeapTupleHeaderGetXmin(tuple->t_data));
+						 HeapTupleGetXmin(tuple));
 
 	HeapCheckForSerializableConflictOut(valid, relation, tuple, buffer, snapshot);
 
@@ -1699,6 +1709,8 @@ heap_hot_search_buffer(ItemPointer tid, Relation relation, Buffer buffer,
 	Assert(TransactionIdIsValid(RecentXmin));
 	Assert(BufferGetBlockNumber(buffer) == blkno);
 
+	heapTuple->t_self = *tid;
+
 	/* Scan through possible multiple members of HOT-chain */
 	for (;;)
 	{
@@ -1734,6 +1746,7 @@ heap_hot_search_buffer(ItemPointer tid, Relation relation, Buffer buffer,
 		heapTuple->t_data = (HeapTupleHeader) PageGetItem(dp, lp);
 		heapTuple->t_len = ItemIdGetLength(lp);
 		heapTuple->t_tableOid = RelationGetRelid(relation);
+		HeapTupleCopyBaseFromPage(heapTuple, dp, IsToastRelation(relation));
 		ItemPointerSet(&heapTuple->t_self, blkno, offnum);
 
 		/*
@@ -1748,7 +1761,7 @@ heap_hot_search_buffer(ItemPointer tid, Relation relation, Buffer buffer,
 		 */
 		if (TransactionIdIsValid(prev_xmax) &&
 			!TransactionIdEquals(prev_xmax,
-								 HeapTupleHeaderGetXmin(heapTuple->t_data)))
+								 HeapTupleGetXmin(heapTuple)))
 			break;
 
 		/*
@@ -1769,7 +1782,7 @@ heap_hot_search_buffer(ItemPointer tid, Relation relation, Buffer buffer,
 			{
 				ItemPointerSetOffsetNumber(tid, offnum);
 				PredicateLockTID(relation, &heapTuple->t_self, snapshot,
-								 HeapTupleHeaderGetXmin(heapTuple->t_data));
+								 HeapTupleGetXmin(heapTuple));
 				if (all_dead)
 					*all_dead = false;
 				return true;
@@ -1804,7 +1817,7 @@ heap_hot_search_buffer(ItemPointer tid, Relation relation, Buffer buffer,
 				   blkno);
 			offnum = ItemPointerGetOffsetNumber(&heapTuple->t_data->t_ctid);
 			at_chain_start = false;
-			prev_xmax = HeapTupleHeaderGetUpdateXid(heapTuple->t_data);
+			prev_xmax = HeapTupleGetUpdateXidAny(heapTuple);
 		}
 		else
 			break;				/* end of chain */
@@ -1891,13 +1904,14 @@ heap_get_latest_tid(TableScanDesc sscan,
 		tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
 		tp.t_len = ItemIdGetLength(lp);
 		tp.t_tableOid = RelationGetRelid(relation);
+		HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
 
 		/*
 		 * After following a t_ctid link, we might arrive at an unrelated
 		 * tuple.  Check for XMIN match.
 		 */
 		if (TransactionIdIsValid(priorXmax) &&
-			!TransactionIdEquals(priorXmax, HeapTupleHeaderGetXmin(tp.t_data)))
+			!TransactionIdEquals(priorXmax, HeapTupleGetXmin(&tp)))
 		{
 			UnlockReleaseBuffer(buffer);
 			break;
@@ -1916,7 +1930,7 @@ heap_get_latest_tid(TableScanDesc sscan,
 		 * If there's a valid t_ctid link, follow it, else we're done.
 		 */
 		if ((tp.t_data->t_infomask & HEAP_XMAX_INVALID) ||
-			HeapTupleHeaderIsOnlyLocked(tp.t_data) ||
+			HeapTupleIsOnlyLocked(&tp) ||
 			HeapTupleHeaderIndicatesMovedPartitions(tp.t_data) ||
 			ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid))
 		{
@@ -1925,7 +1939,7 @@ heap_get_latest_tid(TableScanDesc sscan,
 		}
 
 		ctid = tp.t_data->t_ctid;
-		priorXmax = HeapTupleHeaderGetUpdateXid(tp.t_data);
+		priorXmax = HeapTupleGetUpdateXidAny(&tp);
 		UnlockReleaseBuffer(buffer);
 	}							/* end of loop */
 }
@@ -1950,7 +1964,7 @@ heap_get_latest_tid(TableScanDesc sscan,
 static void
 UpdateXmaxHintBits(HeapTupleHeader tuple, Buffer buffer, TransactionId xid)
 {
-	Assert(TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple), xid));
+	Assert(TransactionIdEquals(HeapTupleHeaderGetRawXmax(BufferGetPage(buffer), tuple), xid));
 	Assert(!(tuple->t_infomask & HEAP_XMAX_IS_MULTI));
 
 	if (!(tuple->t_infomask & (HEAP_XMAX_COMMITTED | HEAP_XMAX_INVALID)))
@@ -2042,7 +2056,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 	 * Note: below this point, heaptup is the data we actually intend to store
 	 * into the relation; tup is the caller's original untoasted data.
 	 */
-	heaptup = heap_prepare_insert(relation, tup, xid, cid, options);
+	heaptup = heap_prepare_insert(relation, tup, cid, options);
 
 	/*
 	 * Find buffer to insert this tuple into.  If the page is all visible,
@@ -2069,6 +2083,9 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 	 */
 	CheckForSerializableConflictIn(relation, NULL, InvalidBlockNumber);
 
+	heap_page_prepare_for_xid(relation, buffer, xid, false);
+	HeapTupleSetXmin(heaptup, xid);
+
 	/* NO EREPORT(ERROR) from here till changes are logged */
 	START_CRIT_SECTION();
 
@@ -2144,12 +2161,23 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 		{
 			xlrec.flags |= XLH_INSERT_CONTAINS_NEW_TUPLE;
 			bufflags |= REGBUF_KEEP_DATA;
-
-			if (IsToastRelation(relation))
-				xlrec.flags |= XLH_INSERT_ON_TOAST_RELATION;
 		}
 
+		if (IsToastRelation(relation))
+			xlrec.flags |= XLH_INSERT_ON_TOAST_RELATION;
+
 		XLogBeginInsert();
+
+		if (info & XLOG_HEAP_INIT_PAGE)
+		{
+			char	   *base;
+
+			base = IsToastRelation(relation) ?
+						(char *) &ToastPageGetSpecial(page)->pd_xid_base :
+						(char *) &HeapPageGetSpecial(page)->pd_xid_base;
+			XLogRegisterData(base, sizeof(TransactionId));
+		}
+
 		XLogRegisterData((char *) &xlrec, SizeOfHeapInsert);
 
 		xlhdr.t_infomask2 = heaptup->t_data->t_infomask2;
@@ -2204,6 +2232,532 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 	}
 }
 
+static void
+xid_min_max(ShortTransactionId *min, ShortTransactionId *max,
+			ShortTransactionId xid,
+			bool *found)
+{
+	Assert(TransactionIdIsNormal(xid));
+	Assert(xid <= MaxShortTransactionId);
+
+	if (!*found)
+	{
+		*min = *max = xid;
+		*found = true;
+	}
+	else
+	{
+		*min = Min(*min, xid);
+		*max = Max(*max, xid);
+	}
+}
+
+/*
+ * Find minimum and maximum short transaction ids which occurs in the page.
+ */
+static bool
+heap_page_xid_min_max(Page page, bool multi,
+					  ShortTransactionId *min, ShortTransactionId *max,
+					  bool is_toast)
+{
+	bool				found;
+	OffsetNumber		offnum,
+						maxoff;
+	ItemId				itemid;
+	HeapTupleHeader		htup;
+
+	maxoff = PageGetMaxOffsetNumber(page);
+	found = false;
+
+	Assert(!multi || !is_toast);
+
+	for (offnum = FirstOffsetNumber;
+		 offnum <= maxoff;
+		 offnum = OffsetNumberNext(offnum))
+	{
+		itemid = PageGetItemId(page, offnum);
+
+		if (!ItemIdIsNormal(itemid))
+			continue;
+
+		htup = (HeapTupleHeader) PageGetItem(page, itemid);
+
+		if (!multi)
+		{
+			Assert(!is_toast || !(htup->t_infomask & HEAP_XMAX_IS_MULTI));
+
+			if (TransactionIdIsNormal(htup->t_choice.t_heap.t_xmin) &&
+				!HeapTupleHeaderXminFrozen(htup))
+			{
+				xid_min_max(min, max, htup->t_choice.t_heap.t_xmin, &found);
+			}
+
+			if (htup->t_infomask & HEAP_XMAX_INVALID)
+				continue;
+
+			if ((htup->t_infomask & HEAP_XMAX_IS_MULTI) &&
+				(!(htup->t_infomask & HEAP_XMAX_LOCK_ONLY)))
+			{
+				TransactionId			update_xid;
+				ShortTransactionId		xid;
+
+				Assert(!is_toast);
+				update_xid = MultiXactIdGetUpdateXid(HeapTupleHeaderGetRawXmax(page, htup),
+													 htup->t_infomask);
+				xid = NormalTransactionIdToShort(HeapPageGetSpecial(page)->pd_xid_base,
+												 update_xid);
+
+				xid_min_max(min, max, xid, &found);
+			}
+		}
+
+		if (!TransactionIdIsNormal(htup->t_choice.t_heap.t_xmax))
+			continue;
+
+		if (multi != (bool) (htup->t_infomask & HEAP_XMAX_IS_MULTI))
+			continue;
+
+		xid_min_max(min, max, htup->t_choice.t_heap.t_xmax, &found);
+	}
+
+	Assert(!found || (*min > InvalidTransactionId && *max <= MaxShortTransactionId));
+
+	return found;
+}
+
+/*
+ * Shift xid base in the page.  WAL-logged if buffer is specified.
+ */
+static void
+heap_page_shift_base(Relation relation, Buffer buffer, Page page,
+					 bool multi, int64 delta, bool is_toast)
+{
+	TransactionId	   *xid_base,
+					   *multi_base;
+	OffsetNumber		offnum,
+						maxoff;
+	ItemId				itemid;
+	HeapTupleHeader		htup;
+
+	xid_base = multi_base = NULL;
+
+	START_CRIT_SECTION();
+	if (is_toast)
+	{
+		Assert(!multi);
+		xid_base = &ToastPageGetSpecial(page)->pd_xid_base;
+	}
+	else
+	{
+		HeapPageSpecial		special;
+
+		special = HeapPageGetSpecial(page);
+		xid_base = &special->pd_xid_base;
+		multi_base = &special->pd_multi_base;
+	}
+
+	/* Iterate over page items */
+	maxoff = PageGetMaxOffsetNumber(page);
+	for (offnum = FirstOffsetNumber;
+		 offnum <= maxoff;
+		 offnum = OffsetNumberNext(offnum))
+	{
+		itemid = PageGetItemId(page, offnum);
+
+		if (!ItemIdIsNormal(itemid))
+			continue;
+
+		htup = (HeapTupleHeader) PageGetItem(page, itemid);
+
+		/* Apply xid shift to heap tuple */
+		if (!multi)
+		{
+			/* shift xmin */
+			if (TransactionIdIsNormal(htup->t_choice.t_heap.t_xmin) &&
+				!HeapTupleHeaderXminFrozen(htup))
+			{
+				Assert(htup->t_choice.t_heap.t_xmin - delta >= FirstNormalTransactionId);
+				Assert(htup->t_choice.t_heap.t_xmin - delta <= MaxShortTransactionId);
+				htup->t_choice.t_heap.t_xmin -= delta;
+			}
+		}
+
+		/* shift xmax */
+		if (!TransactionIdIsNormal(htup->t_choice.t_heap.t_xmax))
+			continue;
+
+		if (multi != (bool) (htup->t_infomask & HEAP_XMAX_IS_MULTI))
+			continue;
+
+		Assert(htup->t_choice.t_heap.t_xmax - delta >= FirstNormalTransactionId);
+		Assert(htup->t_choice.t_heap.t_xmax - delta <= MaxShortTransactionId);
+		htup->t_choice.t_heap.t_xmax -= delta;
+	}
+
+	/* Apply xid shift to base as well */
+	if (!multi)
+		*xid_base += delta;
+	else
+		*multi_base += delta;
+
+	if (BufferIsValid(buffer))
+		MarkBufferDirty(buffer);
+
+	/* Write WAL record if needed */
+	if (relation && RelationNeedsWAL(relation))
+	{
+		XLogRecPtr			recptr;
+		xl_heap_base_shift	xlrec;
+
+		xlrec.delta = delta;
+		xlrec.multi = multi;
+		xlrec.flags = 0;
+		if (IsToastRelation(relation))
+			xlrec.flags |= XLH_BASE_SHIFT_ON_TOAST_RELATION;
+
+		XLogBeginInsert();
+		XLogRegisterData((char *) &xlrec, SizeOfHeapBaseShift);
+		XLogRegisterBuffer(0, buffer, REGBUF_STANDARD);
+
+		recptr = XLogInsert(RM_HEAP3_ID, XLOG_HEAP3_BASE_SHIFT);
+
+		PageSetLSN(page, recptr);
+	}
+
+	END_CRIT_SECTION();
+}
+
+/*
+ * Freeze xids in the single heap page.  Useful when we can't fit new xid even
+ * with base shift.
+ */
+static void
+freeze_single_heap_page(Relation relation, Buffer buffer)
+{
+	Page					page = BufferGetPage(buffer);
+	OffsetNumber			offnum,
+							maxoff;
+	HeapTupleData			tuple;
+	int						nfrozen = 0;
+	xl_heap_freeze_tuple   *frozen;
+	TransactionId			OldestXmin,
+							FreezeXid;
+	MultiXactId				OldestMxact,
+							MultiXactCutoff;
+	GlobalVisState		   *vistest;
+	ItemId					itemid;
+	bool					tuple_totally_frozen;
+	int						ndeleted,
+							nnewlpdead;
+
+	vacuum_set_xid_limits(relation, 0, 0, 0, 0, &OldestMxact,
+						  &OldestXmin, &FreezeXid, &MultiXactCutoff);
+
+	vistest = GlobalVisTestFor(relation);
+
+	ndeleted = heap_page_prune(relation, buffer, vistest, InvalidTransactionId, 0,
+								&nnewlpdead, &offnum, false);
+	if (ndeleted > nnewlpdead)
+		pgstat_update_heap_dead_tuples(relation,
+									   ndeleted - nnewlpdead);
+
+	/*
+	 * Now scan the page to collect vacuumable items and check for tuples
+	 * requiring freezing.
+	 */
+	maxoff = PageGetMaxOffsetNumber(page);
+	frozen = palloc(sizeof(xl_heap_freeze_tuple) * MaxHeapTuplesPerPage);
+
+	/*
+	 * Note: If you change anything in the loop below, also look at
+	 * heap_page_is_all_visible to see if that needs to be changed.
+	 */
+	for (offnum = FirstOffsetNumber;
+		 offnum <= maxoff;
+		 offnum = OffsetNumberNext(offnum))
+	{
+		TransactionId	NewRelfrozenXid;
+		MultiXactId		NewRelminMxid;
+
+		itemid = PageGetItemId(page, offnum);
+
+		if (!ItemIdIsNormal(itemid))
+			continue;
+
+		tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
+		tuple.t_len = ItemIdGetLength(itemid);
+		tuple.t_tableOid = RelationGetRelid(relation);
+		HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(relation));
+
+		/*
+		 * Each non-removable tuple must be checked to see if it needs
+		 * freezing.  Note we already have exclusive buffer lock.
+		 */
+		if (heap_prepare_freeze_tuple(&tuple,
+									  relation->rd_rel->relfrozenxid,
+									  relation->rd_rel->relminmxid,
+									  FreezeXid, MultiXactCutoff,
+									  &frozen[nfrozen], &tuple_totally_frozen,
+									  &NewRelfrozenXid, &NewRelminMxid))
+			frozen[nfrozen++].offset = offnum;
+	}
+
+	/*
+	 * If we froze any tuples, mark the buffer dirty, and write a WAL record
+	 * recording the changes.  We must log the changes to be crash-safe
+	 * against future truncation of CLOG.
+	 */
+	if (nfrozen > 0)
+	{
+		int					i;
+		ItemId				itemid;
+		HeapTupleHeader		htup;
+
+		START_CRIT_SECTION();
+
+		MarkBufferDirty(buffer);
+
+		/* execute collected freezes */
+		for (i = 0; i < nfrozen; i++)
+		{
+			itemid = PageGetItemId(page, frozen[i].offset);
+			htup = (HeapTupleHeader) PageGetItem(page, itemid);
+			heap_execute_freeze_tuple_page(page, htup, &frozen[i],
+										   IsToastRelation(relation));
+		}
+
+		/* Now WAL-log freezing if necessary */
+		if (RelationNeedsWAL(relation))
+		{
+			XLogRecPtr	recptr;
+
+			recptr = log_heap_freeze(relation, buffer, FreezeXid,
+									 frozen, nfrozen);
+			PageSetLSN(page, recptr);
+		}
+
+		END_CRIT_SECTION();
+	}
+
+	pfree(frozen);
+
+	return;
+}
+
+static void
+heap_page_apply_delta(Relation relation, Buffer buffer, Page page,
+					  TransactionId xid, bool multi,
+					  TransactionId base, int64 delta, bool is_toast)
+{
+	Assert(xid >= base + delta + FirstNormalTransactionId);
+	Assert(xid <= base + delta + MaxShortTransactionId);
+
+	heap_page_shift_base(relation, buffer, page, multi, delta,
+						 is_toast);
+
+#ifdef USE_ASSERT_CHECKING
+	{
+		if (is_toast)
+			base = ToastPageGetSpecial(page)->pd_xid_base;
+		else
+			base = multi ? HeapPageGetSpecial(page)->pd_multi_base :
+						   HeapPageGetSpecial(page)->pd_xid_base;
+		Assert(xid >= base + FirstNormalTransactionId);
+		Assert(xid <= base + MaxShortTransactionId);
+	}
+#endif /* USE_ASSERT_CHECKING */
+}
+
+static void
+heap_page_check_delta(Relation relation, Buffer buffer,
+					  TransactionId xid, TransactionId base,
+					  ShortTransactionId min, ShortTransactionId max,
+					  int64 delta, int64 *freeDelta, int64 *requiredDelta)
+{
+	BufferDesc	   *buf;
+	char		   *path;
+	BackendId		backend;
+
+	Assert((freeDelta == NULL) == (requiredDelta == NULL));
+
+	if (xid >= base + delta + FirstNormalTransactionId &&
+		xid <= base + delta + MaxShortTransactionId)
+	{
+		return;
+	}
+
+	if (buffer == InvalidBuffer)
+		return;
+
+	if (BufferIsLocal(buffer))
+	{
+		buf = GetLocalBufferDescriptor(-buffer - 1);
+		backend = MyBackendId;
+	}
+	else
+	{
+		buf = GetBufferDescriptor(buffer - 1);
+		backend = InvalidBackendId;
+	}
+
+	path = relpathbackend(buf->tag.rlocator, backend, buf->tag.forkNum);
+
+	if (freeDelta == NULL)
+		elog(FATAL, "Fatal xid base calculation error: xid = %llu, base = %llu, min = %u, max = %u, delta = %lld (rel=%s, blockNum=%u)",
+					(unsigned long long) xid, (unsigned long long) base,
+					min, max,
+					(long long) delta,
+					path, buf->tag.blockNum);
+	else
+		elog(FATAL, "Fatal xid base calculation error: xid = %llu, base = %llu, min = %u, max = %u, freeDelta = %lld, requiredDelta = %lld, delta = %lld (rel=%s, blockNum=%u)",
+					(unsigned long long) xid, (unsigned long long) base,
+					min, max,
+					(long long) *freeDelta, (long long) *requiredDelta,
+					(long long) delta,
+					path, buf->tag.blockNum);
+}
+
+static int
+heap_page_try_prepare_for_xid(Relation relation, Buffer buffer, Page page,
+							  TransactionId xid, bool multi, bool is_toast)
+{
+	TransactionId		base;
+	ShortTransactionId	min = InvalidTransactionId,
+						max = InvalidTransactionId;
+	int64				delta,
+						freeDelta,
+						requiredDelta;
+
+	if (is_toast)
+	{
+		Assert(!multi);
+		base = ToastPageGetSpecial(page)->pd_xid_base;
+	}
+	else
+	{
+		HeapPageSpecial		special;
+
+		special = HeapPageGetSpecial(page);
+		base = multi ? special->pd_multi_base : special->pd_xid_base;
+	}
+
+	/* If xid fits the page no action needed. */
+	if (xid >= base + FirstNormalTransactionId &&
+		xid <= base + MaxShortTransactionId)
+	{
+		return 0;
+	}
+
+	/* No items on the page? */
+	if (!heap_page_xid_min_max(page, multi, &min, &max, is_toast))
+	{
+		delta = (int64) (xid - FirstNormalTransactionId) - (int64) base;
+		heap_page_check_delta(relation, buffer, xid, base, min, max, delta,
+							  NULL, NULL);
+		heap_page_apply_delta(relation, buffer, page, xid, multi, base, delta,
+							  is_toast);
+		return 0;
+	}
+
+	/* Can we just shift base on the page? */
+	if (xid < base + FirstNormalTransactionId)
+	{
+		freeDelta = MaxShortTransactionId - max;
+		requiredDelta = (base + FirstNormalTransactionId) - xid;
+		/* Shouldn't consider setting base less than 0 */
+		freeDelta = Min(freeDelta, base);
+
+		if (requiredDelta > freeDelta)
+			return -1;
+
+		delta  = -(freeDelta + requiredDelta) / 2;
+	}
+	else
+	{
+		freeDelta = min - FirstNormalTransactionId;
+		requiredDelta = xid - (base + MaxShortTransactionId);
+
+		if (requiredDelta > freeDelta)
+			return -1;
+
+		delta = (freeDelta + requiredDelta) / 2;
+	}
+
+	heap_page_check_delta(relation, buffer, xid, base, min, max,
+						  delta, &freeDelta, &requiredDelta);
+	heap_page_apply_delta(relation, buffer, page, xid, multi, base,
+						  delta, is_toast);
+
+	return 1;
+}
+
+/*
+ * Ensure that given xid fits base of given page.
+ */
+bool
+heap_page_prepare_for_xid(Relation relation, Buffer buffer,
+						  TransactionId xid, bool multi)
+{
+	Page		page = BufferGetPage(buffer);
+	int			res;
+
+	/* "Double xmax" page format doesn't require any preparation */
+	if (HeapPageIsDoubleXmax(page))
+		return false;
+
+	if (!TransactionIdIsNormal(xid))
+		return false;
+
+	res = heap_page_try_prepare_for_xid(relation, buffer, page, xid, multi,
+										IsToastRelation(relation));
+	if (res != -1)
+		return res == 1;
+
+	/* Have to try freeing the page... */
+	freeze_single_heap_page(relation, buffer);
+
+	res = heap_page_try_prepare_for_xid(relation, buffer, page, xid, multi,
+										IsToastRelation(relation));
+	if (res != -1)
+		return res == 1;
+
+	elog(ERROR, "could not fit xid into page");
+
+	return false;
+}
+
+/*
+ * Ensure that given xid fits base of given page.
+ */
+void
+rewrite_page_prepare_for_xid(Page page, HeapTuple tup, bool is_toast)
+{
+	TransactionId	xid;
+	int				res;
+
+	/* xmin */
+	xid = HeapTupleGetXmin(tup);
+	if (TransactionIdIsNormal(xid))
+	{
+		res = heap_page_try_prepare_for_xid(NULL, InvalidBuffer, page, xid,
+											false, is_toast);
+		if (res == -1)
+			elog(ERROR, "could not fit xid into page");
+	}
+
+	/* xmax */
+	xid = HeapTupleGetRawXmax(tup);
+	if (TransactionIdIsNormal(xid))
+	{
+		res = heap_page_try_prepare_for_xid(NULL, InvalidBuffer, page, xid,
+											tup->t_data->t_infomask & HEAP_XMAX_IS_MULTI,
+											is_toast);
+		if (res == -1)
+			elog(ERROR, "could not fit xid into page");
+	}
+}
+
+
 /*
  * Subroutine for heap_insert(). Prepares a tuple for insertion. This sets the
  * tuple header fields and toasts the tuple if necessary.  Returns a toasted
@@ -2211,7 +2765,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid,
  * that in any case, the header fields are also set in the original tuple.
  */
 static HeapTuple
-heap_prepare_insert(Relation relation, HeapTuple tup, TransactionId xid,
+heap_prepare_insert(Relation relation, HeapTuple tup,
 					CommandId cid, int options)
 {
 	/*
@@ -2228,12 +2782,12 @@ heap_prepare_insert(Relation relation, HeapTuple tup, TransactionId xid,
 	tup->t_data->t_infomask &= ~(HEAP_XACT_MASK);
 	tup->t_data->t_infomask2 &= ~(HEAP2_XACT_MASK);
 	tup->t_data->t_infomask |= HEAP_XMAX_INVALID;
-	HeapTupleHeaderSetXmin(tup->t_data, xid);
+	HeapTupleSetXmin(tup, InvalidTransactionId);
 	if (options & HEAP_INSERT_FROZEN)
 		HeapTupleHeaderSetXminFrozen(tup->t_data);
 
 	HeapTupleHeaderSetCmin(tup->t_data, cid);
-	HeapTupleHeaderSetXmax(tup->t_data, 0); /* for cleanliness */
+	HeapTupleSetXmax(tup, 0);	/* for cleanliness */
 	tup->t_tableOid = RelationGetRelid(relation);
 
 	/*
@@ -2296,8 +2850,7 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
 		tuple = ExecFetchSlotHeapTuple(slots[i], true, NULL);
 		slots[i]->tts_tableOid = RelationGetRelid(relation);
 		tuple->t_tableOid = slots[i]->tts_tableOid;
-		heaptuples[i] = heap_prepare_insert(relation, tuple, xid, cid,
-											options);
+		heaptuples[i] = heap_prepare_insert(relation, tuple, cid, options);
 	}
 
 	/*
@@ -2353,6 +2906,8 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
 		if (starting_with_empty_page && (options & HEAP_INSERT_FROZEN))
 			all_frozen_set = true;
 
+		heap_page_prepare_for_xid(relation, buffer, xid, false);
+
 		/* NO EREPORT(ERROR) from here till changes are logged */
 		START_CRIT_SECTION();
 
@@ -2360,6 +2915,7 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
 		 * RelationGetBufferForTuple has ensured that the first tuple fits.
 		 * Put that on the page, and then as many other tuples as fit.
 		 */
+		HeapTupleSetXmin(heaptuples[ndone], xid);
 		RelationPutHeapTuple(relation, buffer, heaptuples[ndone], false);
 
 		/*
@@ -2376,6 +2932,7 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
 			if (PageGetHeapFreeSpace(page) < MAXALIGN(heaptup->t_len) + saveFreeSpace)
 				break;
 
+			HeapTupleSetXmin(heaptup, xid);
 			RelationPutHeapTuple(relation, buffer, heaptup, false);
 
 			/*
@@ -2511,6 +3068,17 @@ heap_multi_insert(Relation relation, TupleTableSlot **slots, int ntuples,
 				bufflags |= REGBUF_KEEP_DATA;
 
 			XLogBeginInsert();
+
+			if (info & XLOG_HEAP_INIT_PAGE)
+			{
+				char	   *base;
+
+				base = IsToastRelation(relation) ?
+							(char *) &ToastPageGetSpecial(page)->pd_xid_base :
+							(char *) &HeapPageGetSpecial(page)->pd_xid_base;
+				XLogRegisterData(base, sizeof(TransactionId));
+			}
+
 			XLogRegisterData((char *) xlrec, tupledata - scratch.data);
 			XLogRegisterBuffer(0, buffer, REGBUF_STANDARD | bufflags);
 
@@ -2731,6 +3299,7 @@ heap_delete(Relation relation, ItemPointer tid,
 	tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
 	tp.t_len = ItemIdGetLength(lp);
 	tp.t_self = *tid;
+	HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
 
 l1:
 	result = HeapTupleSatisfiesUpdate(&tp, cid, buffer);
@@ -2748,7 +3317,7 @@ l1:
 		uint16		infomask;
 
 		/* must copy state data before unlocking buffer */
-		xwait = HeapTupleHeaderGetRawXmax(tp.t_data);
+		xwait = HeapTupleGetRawXmax(&tp);
 		infomask = tp.t_data->t_infomask;
 
 		/*
@@ -2787,13 +3356,16 @@ l1:
 								NULL);
 				LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 
+				/* Copy possibly updated xid base after relocking */
+				HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
+
 				/*
 				 * If xwait had just locked the tuple then some other xact
 				 * could update this tuple before we get to this point.  Check
 				 * for xmax change, and start over if so.
 				 */
 				if (xmax_infomask_changed(tp.t_data->t_infomask, infomask) ||
-					!TransactionIdEquals(HeapTupleHeaderGetRawXmax(tp.t_data),
+					!TransactionIdEquals(HeapTupleGetRawXmax(&tp),
 										 xwait))
 					goto l1;
 			}
@@ -2820,13 +3392,16 @@ l1:
 			XactLockTableWait(xwait, relation, &(tp.t_self), XLTW_Delete);
 			LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 
+			/* Copy possibly updated xid base after relocking */
+			HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
+
 			/*
 			 * xwait is done, but if xwait had just locked the tuple then some
 			 * other xact could update this tuple before we get to this point.
 			 * Check for xmax change, and start over if so.
 			 */
 			if (xmax_infomask_changed(tp.t_data->t_infomask, infomask) ||
-				!TransactionIdEquals(HeapTupleHeaderGetRawXmax(tp.t_data),
+				!TransactionIdEquals(HeapTupleGetRawXmax(&tp),
 									 xwait))
 				goto l1;
 
@@ -2840,7 +3415,7 @@ l1:
 		 */
 		if ((tp.t_data->t_infomask & HEAP_XMAX_INVALID) ||
 			HEAP_XMAX_IS_LOCKED_ONLY(tp.t_data->t_infomask) ||
-			HeapTupleHeaderIsOnlyLocked(tp.t_data))
+			HeapTupleIsOnlyLocked(&tp))
 			result = TM_Ok;
 		else if (!ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid))
 			result = TM_Updated;
@@ -2865,9 +3440,9 @@ l1:
 		Assert(result != TM_Updated ||
 			   !ItemPointerEquals(&tp.t_self, &tp.t_data->t_ctid));
 		tmfd->ctid = tp.t_data->t_ctid;
-		tmfd->xmax = HeapTupleHeaderGetUpdateXid(tp.t_data);
+		tmfd->xmax = HeapTupleGetUpdateXidAny(&tp);
 		if (result == TM_SelfModified)
-			tmfd->cmax = HeapTupleHeaderGetCmax(tp.t_data);
+			tmfd->cmax = HeapTupleGetCmax(&tp);
 		else
 			tmfd->cmax = InvalidCommandId;
 		UnlockReleaseBuffer(buffer);
@@ -2890,7 +3465,7 @@ l1:
 	CheckForSerializableConflictIn(relation, tid, BufferGetBlockNumber(buffer));
 
 	/* replace cid with a combo CID if necessary */
-	HeapTupleHeaderAdjustCmax(tp.t_data, &cid, &iscombo);
+	HeapTupleHeaderAdjustCmax(&tp, &cid, &iscombo);
 
 	/*
 	 * Compute replica identity tuple before entering the critical section so
@@ -2908,11 +3483,20 @@ l1:
 	 */
 	MultiXactIdSetOldestMember();
 
-	compute_new_xmax_infomask(HeapTupleHeaderGetRawXmax(tp.t_data),
+	compute_new_xmax_infomask(HeapTupleGetRawXmax(&tp),
 							  tp.t_data->t_infomask, tp.t_data->t_infomask2,
 							  xid, LockTupleExclusive, true,
 							  &new_xmax, &new_infomask, &new_infomask2);
 
+#ifdef USE_ASSERT_CHECKING
+	if (IsToastRelation(relation))
+		Assert((new_infomask & HEAP_XMAX_IS_MULTI) == false);
+#endif
+
+	heap_page_prepare_for_xid(relation, buffer, new_xmax,
+							  (new_infomask & HEAP_XMAX_IS_MULTI) ? true : false);
+	HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
+
 	START_CRIT_SECTION();
 
 	/*
@@ -2922,7 +3506,7 @@ l1:
 	 * the subsequent page pruning will be a no-op and the hint will be
 	 * cleared.
 	 */
-	PageSetPrunable(page, xid);
+	PageSetPrunable(page, xid, IsToastRelation(relation));
 
 	if (PageIsAllVisible(page))
 	{
@@ -2938,10 +3522,15 @@ l1:
 	tp.t_data->t_infomask |= new_infomask;
 	tp.t_data->t_infomask2 |= new_infomask2;
 	HeapTupleHeaderClearHotUpdated(tp.t_data);
-	HeapTupleHeaderSetXmax(tp.t_data, new_xmax);
+	HeapTupleSetXmax(&tp, new_xmax);
+	if (IsToastRelation(relation))
+		ToastTupleHeaderSetXmax(page, &tp);
+	else
+		HeapTupleHeaderSetXmax(page, &tp);
 	HeapTupleHeaderSetCmax(tp.t_data, cid, iscombo);
 	/* Make sure there is no forward chain link in t_ctid */
 	tp.t_data->t_ctid = tp.t_self;
+	HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
 
 	/* Signal that this is actually a move into another partition */
 	if (changingPart)
@@ -2977,6 +3566,8 @@ l1:
 											  tp.t_data->t_infomask2);
 		xlrec.offnum = ItemPointerGetOffsetNumber(&tp.t_self);
 		xlrec.xmax = new_xmax;
+		if (IsToastRelation(relation))
+			xlrec.flags |= XLH_DELETE_PAGE_ON_TOAST_RELATION;
 
 		if (old_key_tuple != NULL)
 		{
@@ -3132,7 +3723,8 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 	HeapTuple	heaptup;
 	HeapTuple	old_key_tuple = NULL;
 	bool		old_key_copied = false;
-	Page		page;
+	Page		page,
+				newpage;
 	BlockNumber block;
 	MultiXactStatus mxact_status;
 	Buffer		buffer,
@@ -3225,6 +3817,7 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 	oldtup.t_data = (HeapTupleHeader) PageGetItem(page, lp);
 	oldtup.t_len = ItemIdGetLength(lp);
 	oldtup.t_self = *otid;
+	HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
 
 	/* the new tuple is ready, except for this: */
 	newtup->t_tableOid = RelationGetRelid(relation);
@@ -3318,7 +3911,7 @@ l2:
 		 */
 
 		/* must copy state data before unlocking buffer */
-		xwait = HeapTupleHeaderGetRawXmax(oldtup.t_data);
+		xwait = HeapTupleGetRawXmax(&oldtup);
 		infomask = oldtup.t_data->t_infomask;
 
 		/*
@@ -3369,6 +3962,7 @@ l2:
 				checked_lockers = true;
 				locker_remains = remain != 0;
 				LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
+				HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
 
 				/*
 				 * If xwait had just locked the tuple then some other xact
@@ -3377,7 +3971,7 @@ l2:
 				 */
 				if (xmax_infomask_changed(oldtup.t_data->t_infomask,
 										  infomask) ||
-					!TransactionIdEquals(HeapTupleHeaderGetRawXmax(oldtup.t_data),
+					!TransactionIdEquals(HeapTupleGetRawXmax(&oldtup),
 										 xwait))
 					goto l2;
 			}
@@ -3403,7 +3997,7 @@ l2:
 			 * subxact aborts.
 			 */
 			if (!HEAP_XMAX_IS_LOCKED_ONLY(oldtup.t_data->t_infomask))
-				update_xact = HeapTupleGetUpdateXid(oldtup.t_data);
+				update_xact = HeapTupleGetUpdateXid(&oldtup);
 			else
 				update_xact = InvalidTransactionId;
 
@@ -3451,6 +4045,8 @@ l2:
 			checked_lockers = true;
 			LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 
+			HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
+
 			/*
 			 * xwait is done, but if xwait had just locked the tuple then some
 			 * other xact could update this tuple before we get to this point.
@@ -3458,7 +4054,7 @@ l2:
 			 */
 			if (xmax_infomask_changed(oldtup.t_data->t_infomask, infomask) ||
 				!TransactionIdEquals(xwait,
-									 HeapTupleHeaderGetRawXmax(oldtup.t_data)))
+									 HeapTupleGetRawXmax(&oldtup)))
 				goto l2;
 
 			/* Otherwise check if it committed or aborted */
@@ -3495,9 +4091,9 @@ l2:
 		Assert(result != TM_Updated ||
 			   !ItemPointerEquals(&oldtup.t_self, &oldtup.t_data->t_ctid));
 		tmfd->ctid = oldtup.t_data->t_ctid;
-		tmfd->xmax = HeapTupleHeaderGetUpdateXid(oldtup.t_data);
+		tmfd->xmax = HeapTupleGetUpdateXidAny(&oldtup);
 		if (result == TM_SelfModified)
-			tmfd->cmax = HeapTupleHeaderGetCmax(oldtup.t_data);
+			tmfd->cmax = HeapTupleGetCmax(&oldtup);
 		else
 			tmfd->cmax = InvalidCommandId;
 		UnlockReleaseBuffer(buffer);
@@ -3527,6 +4123,7 @@ l2:
 		LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
 		visibilitymap_pin(relation, block, &vmbuffer);
 		LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
+		HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
 		goto l2;
 	}
 
@@ -3536,7 +4133,7 @@ l2:
 	 * If the tuple we're updating is locked, we need to preserve the locking
 	 * info in the old tuple's Xmax.  Prepare a new Xmax value for this.
 	 */
-	compute_new_xmax_infomask(HeapTupleHeaderGetRawXmax(oldtup.t_data),
+	compute_new_xmax_infomask(HeapTupleGetRawXmax(&oldtup),
 							  oldtup.t_data->t_infomask,
 							  oldtup.t_data->t_infomask2,
 							  xid, *lockmode, true,
@@ -3555,7 +4152,7 @@ l2:
 		(checked_lockers && !locker_remains))
 		xmax_new_tuple = InvalidTransactionId;
 	else
-		xmax_new_tuple = HeapTupleHeaderGetRawXmax(oldtup.t_data);
+		xmax_new_tuple = HeapTupleGetRawXmax(&oldtup);
 
 	if (!TransactionIdIsValid(xmax_new_tuple))
 	{
@@ -3588,17 +4185,15 @@ l2:
 	 */
 	newtup->t_data->t_infomask &= ~(HEAP_XACT_MASK);
 	newtup->t_data->t_infomask2 &= ~(HEAP2_XACT_MASK);
-	HeapTupleHeaderSetXmin(newtup->t_data, xid);
 	HeapTupleHeaderSetCmin(newtup->t_data, cid);
 	newtup->t_data->t_infomask |= HEAP_UPDATED | infomask_new_tuple;
 	newtup->t_data->t_infomask2 |= infomask2_new_tuple;
-	HeapTupleHeaderSetXmax(newtup->t_data, xmax_new_tuple);
 
 	/*
 	 * Replace cid with a combo CID if necessary.  Note that we already put
 	 * the plain cid into the new tuple.
 	 */
-	HeapTupleHeaderAdjustCmax(oldtup.t_data, &cid, &iscombo);
+	HeapTupleHeaderAdjustCmax(&oldtup, &cid, &iscombo);
 
 	/*
 	 * If the toaster needs to be activated, OR if the new tuple will not fit
@@ -3628,7 +4223,7 @@ l2:
 
 	newtupsize = MAXALIGN(newtup->t_len);
 
-	if (need_toast || newtupsize > pagefree)
+	if (need_toast || newtupsize > pagefree || HeapPageIsDoubleXmax(page))
 	{
 		TransactionId xmax_lock_old_tuple;
 		uint16		infomask_lock_old_tuple,
@@ -3653,7 +4248,7 @@ l2:
 		 * updating, because the potentially created multixact would otherwise
 		 * be wrong.
 		 */
-		compute_new_xmax_infomask(HeapTupleHeaderGetRawXmax(oldtup.t_data),
+		compute_new_xmax_infomask(HeapTupleGetRawXmax(&oldtup),
 								  oldtup.t_data->t_infomask,
 								  oldtup.t_data->t_infomask2,
 								  xid, *lockmode, false,
@@ -3662,6 +4257,15 @@ l2:
 
 		Assert(HEAP_XMAX_IS_LOCKED_ONLY(infomask_lock_old_tuple));
 
+#ifdef USE_ASSERT_CHECKING
+		if (IsToastRelation(relation))
+			Assert((infomask_lock_old_tuple & HEAP_XMAX_IS_MULTI) == false);
+#endif
+
+		heap_page_prepare_for_xid(relation, buffer, xmax_lock_old_tuple,
+								  (infomask_lock_old_tuple & HEAP_XMAX_IS_MULTI) ? true : false);
+		HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
+
 		START_CRIT_SECTION();
 
 		/* Clear obsolete visibility flags ... */
@@ -3670,10 +4274,12 @@ l2:
 		HeapTupleClearHotUpdated(&oldtup);
 		/* ... and store info about transaction updating this tuple */
 		Assert(TransactionIdIsValid(xmax_lock_old_tuple));
-		HeapTupleHeaderSetXmax(oldtup.t_data, xmax_lock_old_tuple);
 		oldtup.t_data->t_infomask |= infomask_lock_old_tuple;
 		oldtup.t_data->t_infomask2 |= infomask2_lock_old_tuple;
+		HeapTupleSetXmax(&oldtup, xmax_lock_old_tuple);
+		HeapTupleHeaderSetXmax(page, &oldtup);
 		HeapTupleHeaderSetCmax(oldtup.t_data, cid, iscombo);
+		HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
 
 		/* temporarily make it look not-updated, but locked */
 		oldtup.t_data->t_ctid = oldtup.t_self;
@@ -3755,7 +4361,11 @@ l2:
 		 */
 		for (;;)
 		{
-			if (newtupsize > pagefree)
+			/*
+			 * We can't fit new tuple to "double xmax" page, since it's
+			 * impossible to set xmin there.
+			 */
+			if (newtupsize > pagefree || HeapPageIsDoubleXmax(page))
 			{
 				/* It doesn't fit, must use RelationGetBufferForTuple. */
 				newbuf = RelationGetBufferForTuple(relation, heaptup->t_len,
@@ -3788,6 +4398,9 @@ l2:
 				break;
 			}
 		}
+
+		/* Copy possibly updated xid base to old tuple after relocking */
+		HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
 	}
 	else
 	{
@@ -3847,6 +4460,47 @@ l2:
 										   id_has_external,
 										   &old_key_copied);
 
+	newpage = BufferGetPage(newbuf);
+
+	/*
+	 * Prepare pages for the current xid, that witten to the new tuple's Xmax
+	 * and old page's pd_prune_xid.
+	 */
+	heap_page_prepare_for_xid(relation, buffer, xid, false);
+	if (newbuf != buffer)
+		heap_page_prepare_for_xid(relation, newbuf, xid, false);
+
+#ifdef USE_ASSERT_CHECKING
+	if (IsToastRelation(relation))
+	{
+		Assert((infomask_old_tuple & HEAP_XMAX_IS_MULTI) == false);
+		Assert((heaptup->t_data->t_infomask & HEAP_XMAX_IS_MULTI) == false);
+	}
+#endif
+
+	/* Prepare pages for tuple's Xmax */
+	heap_page_prepare_for_xid(relation, buffer, xmax_old_tuple,
+							  (infomask_old_tuple & HEAP_XMAX_IS_MULTI) ? true : false);
+	heap_page_prepare_for_xid(relation, newbuf, xmax_new_tuple,
+							  (heaptup->t_data->t_infomask & HEAP_XMAX_IS_MULTI) ? true : false);
+
+	/* Copy possibly updated Xid bases to the both tuples. */
+	HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
+
+	/*
+	 * Set new tuple's Xmin/Xmax, old tuple's Xmin/Xmax were already shifted.
+	 */
+	HeapTupleSetXmin(heaptup, xid);
+	if (IsToastRelation(relation))
+		ToastTupleHeaderSetXmin(newpage, heaptup);
+	else
+		HeapTupleHeaderSetXmin(newpage, heaptup);
+	HeapTupleSetXmax(heaptup, xmax_new_tuple);
+	if (IsToastRelation(relation))
+		ToastTupleHeaderSetXmax(newpage, heaptup);
+	else
+		HeapTupleHeaderSetXmax(newpage, heaptup);
+
 	/* NO EREPORT(ERROR) from here till changes are logged */
 	START_CRIT_SECTION();
 
@@ -3862,7 +4516,9 @@ l2:
 	 * not to optimize for aborts.  Note that heap_xlog_update must be kept in
 	 * sync if this decision changes.
 	 */
-	PageSetPrunable(page, xid);
+
+	Assert(!IsToastRelation(relation));
+	PageSetPrunable(page, xid, false);
 
 	if (use_hot_update)
 	{
@@ -3889,10 +4545,12 @@ l2:
 	oldtup.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
 	/* ... and store info about transaction updating this tuple */
 	Assert(TransactionIdIsValid(xmax_old_tuple));
-	HeapTupleHeaderSetXmax(oldtup.t_data, xmax_old_tuple);
 	oldtup.t_data->t_infomask |= infomask_old_tuple;
 	oldtup.t_data->t_infomask2 |= infomask2_old_tuple;
+	HeapTupleSetXmax(&oldtup, xmax_old_tuple);
+	HeapTupleHeaderSetXmax(page, &oldtup);
 	HeapTupleHeaderSetCmax(oldtup.t_data, cid, iscombo);
+	HeapTupleCopyBaseFromPage(&oldtup, page, IsToastRelation(relation));
 
 	/* record address of new tuple in t_ctid of old one */
 	oldtup.t_data->t_ctid = heaptup->t_self;
@@ -3946,6 +4604,20 @@ l2:
 
 	END_CRIT_SECTION();
 
+	if (newtup != heaptup)
+	{
+		/*
+		 * Set new tuple's Xmin/Xmax only after both xid base preparations.
+		 * Old tuple's Xmin/Xmax were already shifted because old tuple is on
+		 * the page.
+		 */
+		HeapTupleCopyBase(newtup, heaptup);
+		HeapTupleSetXmin(newtup, xid);
+		HeapTupleHeaderSetXmin(newpage, newtup);
+		HeapTupleSetXmax(newtup, xmax_new_tuple);
+		HeapTupleHeaderSetXmax(newpage, newtup);
+	}
+
 	if (newbuf != buffer)
 		LockBuffer(newbuf, BUFFER_LOCK_UNLOCK);
 	LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
@@ -4284,6 +4956,7 @@ heap_lock_tuple(Relation relation, HeapTuple tuple,
 	tuple->t_data = (HeapTupleHeader) PageGetItem(page, lp);
 	tuple->t_len = ItemIdGetLength(lp);
 	tuple->t_tableOid = RelationGetRelid(relation);
+	HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 
 l3:
 	result = HeapTupleSatisfiesUpdate(tuple, cid, *buffer);
@@ -4310,7 +4983,7 @@ l3:
 		ItemPointerData t_ctid;
 
 		/* must copy state data before unlocking buffer */
-		xwait = HeapTupleHeaderGetRawXmax(tuple->t_data);
+		xwait = HeapTupleGetRawXmax(tuple);
 		infomask = tuple->t_data->t_infomask;
 		infomask2 = tuple->t_data->t_infomask2;
 		ItemPointerCopy(&tuple->t_data->t_ctid, &t_ctid);
@@ -4468,11 +5141,13 @@ l3:
 						result = res;
 						/* recovery code expects to have buffer lock held */
 						LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+						HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 						goto failed;
 					}
 				}
 
 				LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+				HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 
 				/*
 				 * Make sure it's still an appropriate lock, else start over.
@@ -4481,7 +5156,7 @@ l3:
 				 * now need to follow the update chain to lock the new
 				 * versions.
 				 */
-				if (!HeapTupleHeaderIsOnlyLocked(tuple->t_data) &&
+				if (!HeapTupleIsOnlyLocked(tuple) &&
 					((tuple->t_data->t_infomask2 & HEAP_KEYS_UPDATED) ||
 					 !updated))
 					goto l3;
@@ -4508,6 +5183,7 @@ l3:
 				!HEAP_XMAX_IS_EXCL_LOCKED(infomask))
 			{
 				LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+				HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 
 				/*
 				 * Make sure it's still an appropriate lock, else start over.
@@ -4536,8 +5212,10 @@ l3:
 					 * meantime, start over.
 					 */
 					LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+					HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
+
 					if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
-						!TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
+						!TransactionIdEquals(HeapTupleGetRawXmax(tuple),
 											 xwait))
 						goto l3;
 
@@ -4548,10 +5226,11 @@ l3:
 			else if (HEAP_XMAX_IS_KEYSHR_LOCKED(infomask))
 			{
 				LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+				HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 
 				/* if the xmax changed in the meantime, start over */
 				if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
-					!TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
+					!TransactionIdEquals(HeapTupleGetRawXmax(tuple),
 										 xwait))
 					goto l3;
 				/* otherwise, we're good */
@@ -4576,8 +5255,10 @@ l3:
 		{
 			/* ... but if the xmax changed in the meantime, start over */
 			LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+			HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
+
 			if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
-				!TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
+				!TransactionIdEquals(HeapTupleGetRawXmax(tuple),
 									 xwait))
 				goto l3;
 			Assert(HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_data->t_infomask));
@@ -4598,6 +5279,7 @@ l3:
 		if (require_sleep && (result == TM_Updated || result == TM_Deleted))
 		{
 			LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+			HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 			goto failed;
 		}
 		else if (require_sleep)
@@ -4623,6 +5305,7 @@ l3:
 				result = TM_WouldBlock;
 				/* recovery code expects to have buffer lock held */
 				LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+				HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 				goto failed;
 			}
 
@@ -4649,6 +5332,7 @@ l3:
 							result = TM_WouldBlock;
 							/* recovery code expects to have buffer lock held */
 							LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+							HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 							goto failed;
 						}
 						break;
@@ -4689,6 +5373,7 @@ l3:
 							result = TM_WouldBlock;
 							/* recovery code expects to have buffer lock held */
 							LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+							HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 							goto failed;
 						}
 						break;
@@ -4715,11 +5400,13 @@ l3:
 					result = res;
 					/* recovery code expects to have buffer lock held */
 					LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+					HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 					goto failed;
 				}
 			}
 
 			LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+			HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 
 			/*
 			 * xwait is done, but if xwait had just locked the tuple then some
@@ -4727,7 +5414,7 @@ l3:
 			 * Check for xmax change, and start over if so.
 			 */
 			if (xmax_infomask_changed(tuple->t_data->t_infomask, infomask) ||
-				!TransactionIdEquals(HeapTupleHeaderGetRawXmax(tuple->t_data),
+				!TransactionIdEquals(HeapTupleGetRawXmax(tuple),
 									 xwait))
 				goto l3;
 
@@ -4755,7 +5442,7 @@ l3:
 		if (!require_sleep ||
 			(tuple->t_data->t_infomask & HEAP_XMAX_INVALID) ||
 			HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_data->t_infomask) ||
-			HeapTupleHeaderIsOnlyLocked(tuple->t_data))
+			HeapTupleIsOnlyLocked(tuple))
 			result = TM_Ok;
 		else if (!ItemPointerEquals(&tuple->t_self, &tuple->t_data->t_ctid))
 			result = TM_Updated;
@@ -4781,9 +5468,9 @@ failed:
 		Assert(result != TM_Updated ||
 			   !ItemPointerEquals(&tuple->t_self, &tuple->t_data->t_ctid));
 		tmfd->ctid = tuple->t_data->t_ctid;
-		tmfd->xmax = HeapTupleHeaderGetUpdateXid(tuple->t_data);
+		tmfd->xmax = HeapTupleGetUpdateXidAny(tuple);
 		if (result == TM_SelfModified)
-			tmfd->cmax = HeapTupleHeaderGetCmax(tuple->t_data);
+			tmfd->cmax = HeapTupleGetCmax(tuple);
 		else
 			tmfd->cmax = InvalidCommandId;
 		goto out_locked;
@@ -4803,10 +5490,11 @@ failed:
 		LockBuffer(*buffer, BUFFER_LOCK_UNLOCK);
 		visibilitymap_pin(relation, block, &vmbuffer);
 		LockBuffer(*buffer, BUFFER_LOCK_EXCLUSIVE);
+		HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
 		goto l3;
 	}
 
-	xmax = HeapTupleHeaderGetRawXmax(tuple->t_data);
+	xmax = HeapTupleGetRawXmax(tuple);
 	old_infomask = tuple->t_data->t_infomask;
 
 	/*
@@ -4828,6 +5516,15 @@ failed:
 							  GetCurrentTransactionId(), mode, false,
 							  &xid, &new_infomask, &new_infomask2);
 
+#ifdef USE_ASSERT_CHECKING
+	if (IsToastRelation(relation))
+		Assert((new_infomask & HEAP_XMAX_IS_MULTI) == false);
+#endif
+
+	heap_page_prepare_for_xid(relation, *buffer, xid,
+							  (new_infomask & HEAP_XMAX_IS_MULTI) ? true : false);
+	HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(relation));
+
 	START_CRIT_SECTION();
 
 	/*
@@ -4846,7 +5543,8 @@ failed:
 	tuple->t_data->t_infomask2 |= new_infomask2;
 	if (HEAP_XMAX_IS_LOCKED_ONLY(new_infomask))
 		HeapTupleHeaderClearHotUpdated(tuple->t_data);
-	HeapTupleHeaderSetXmax(tuple->t_data, xid);
+	HeapTupleSetXmax(tuple, xid);
+	HeapTupleHeaderSetXmax(page, tuple);
 
 	/*
 	 * Make sure there is no forward chain link in t_ctid.  Note that in the
@@ -5440,12 +6138,18 @@ l4:
 			LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
 		}
 
+		/*
+		 * Copy xid base after buffer relocking, it could have changed since
+		 * heap_fetch().
+		 */
+		HeapTupleCopyBaseFromPage(&mytup, BufferGetPage(buf), IsToastRelation(rel));
+
 		/*
 		 * Check the tuple XMIN against prior XMAX, if any.  If we reached the
 		 * end of the chain, we're done, so return success.
 		 */
 		if (TransactionIdIsValid(priorXmax) &&
-			!TransactionIdEquals(HeapTupleHeaderGetXmin(mytup.t_data),
+			!TransactionIdEquals(HeapTupleGetXmin(&mytup),
 								 priorXmax))
 		{
 			result = TM_Ok;
@@ -5457,7 +6161,7 @@ l4:
 		 * (sub)transaction, then we already locked the last live one in the
 		 * chain, thus we're done, so return success.
 		 */
-		if (TransactionIdDidAbort(HeapTupleHeaderGetXmin(mytup.t_data)))
+		if (TransactionIdDidAbort(HeapTupleGetXmin(&mytup)))
 		{
 			result = TM_Ok;
 			goto out_locked;
@@ -5465,7 +6169,7 @@ l4:
 
 		old_infomask = mytup.t_data->t_infomask;
 		old_infomask2 = mytup.t_data->t_infomask2;
-		xmax = HeapTupleHeaderGetRawXmax(mytup.t_data);
+		xmax = HeapTupleGetRawXmax(&mytup);
 
 		/*
 		 * If this tuple version has been updated or locked by some concurrent
@@ -5478,7 +6182,7 @@ l4:
 			TransactionId rawxmax;
 			bool		needwait;
 
-			rawxmax = HeapTupleHeaderGetRawXmax(mytup.t_data);
+			rawxmax = HeapTupleGetRawXmax(&mytup);
 			if (old_infomask & HEAP_XMAX_IS_MULTI)
 			{
 				int			nmembers;
@@ -5619,14 +6323,24 @@ l4:
 								VISIBILITYMAP_ALL_FROZEN))
 			cleared_all_frozen = true;
 
+#ifdef USE_ASSERT_CHECKING
+		if (IsToastRelation(rel))
+			Assert((new_infomask & HEAP_XMAX_IS_MULTI) == false);
+#endif
+
+		heap_page_prepare_for_xid(rel, buf, new_xmax,
+								  (new_infomask & HEAP_XMAX_IS_MULTI) ? true : false);
+		HeapTupleCopyBaseFromPage(&mytup, BufferGetPage(buf), IsToastRelation(rel));
+
 		START_CRIT_SECTION();
 
 		/* ... and set them */
-		HeapTupleHeaderSetXmax(mytup.t_data, new_xmax);
 		mytup.t_data->t_infomask &= ~HEAP_XMAX_BITS;
 		mytup.t_data->t_infomask2 &= ~HEAP_KEYS_UPDATED;
 		mytup.t_data->t_infomask |= new_infomask;
 		mytup.t_data->t_infomask2 |= new_infomask2;
+		HeapTupleSetXmax(&mytup, new_xmax);
+		HeapTupleHeaderSetXmax(BufferGetPage(buf), &mytup);
 
 		MarkBufferDirty(buf);
 
@@ -5660,14 +6374,14 @@ next:
 		if (mytup.t_data->t_infomask & HEAP_XMAX_INVALID ||
 			HeapTupleHeaderIndicatesMovedPartitions(mytup.t_data) ||
 			ItemPointerEquals(&mytup.t_self, &mytup.t_data->t_ctid) ||
-			HeapTupleHeaderIsOnlyLocked(mytup.t_data))
+			HeapTupleIsOnlyLocked(&mytup))
 		{
 			result = TM_Ok;
 			goto out_locked;
 		}
 
 		/* tail recursion */
-		priorXmax = HeapTupleHeaderGetUpdateXid(mytup.t_data);
+		priorXmax = HeapTupleGetUpdateXidAny(&mytup);
 		ItemPointerCopy(&(mytup.t_data->t_ctid), &tupid);
 		UnlockReleaseBuffer(buf);
 	}
@@ -5874,12 +6588,13 @@ heap_abort_speculative(Relation relation, ItemPointer tid)
 	tp.t_data = (HeapTupleHeader) PageGetItem(page, lp);
 	tp.t_len = ItemIdGetLength(lp);
 	tp.t_self = *tid;
+	HeapTupleCopyBaseFromPage(&tp, page, IsToastRelation(relation));
 
 	/*
 	 * Sanity check that the tuple really is a speculatively inserted tuple,
 	 * inserted by us.
 	 */
-	if (tp.t_data->t_choice.t_heap.t_xmin != xid)
+	if (HeapTupleGetRawXmin(&tp) != xid)
 		elog(ERROR, "attempted to kill a tuple inserted by another transaction");
 	if (!(IsToastRelation(relation) || HeapTupleHeaderIsSpeculative(tp.t_data)))
 		elog(ERROR, "attempted to kill a non-speculative tuple");
@@ -5908,7 +6623,9 @@ heap_abort_speculative(Relation relation, ItemPointer tid)
 		prune_xid = relation->rd_rel->relfrozenxid;
 	else
 		prune_xid = TransactionXmin;
-	PageSetPrunable(page, prune_xid);
+	Assert(TransactionIdIsValid(prune_xid));
+	heap_page_prepare_for_xid(relation, buffer, prune_xid, false);
+	PageSetPrunable(page, prune_xid, IsToastRelation(relation));
 
 	/* store transaction information of xact deleting the tuple */
 	tp.t_data->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
@@ -5917,9 +6634,15 @@ heap_abort_speculative(Relation relation, ItemPointer tid)
 	/*
 	 * Set the tuple header xmin to InvalidTransactionId.  This makes the
 	 * tuple immediately invisible everyone.  (In particular, to any
-	 * transactions waiting on the speculative token, woken up later.)
+	 * transactions waiting on the speculative token, woken up later.) Don't
+	 * need to reload xid base from page because InvalidTransactionId doesn't
+	 * require xid base to be valid.
 	 */
-	HeapTupleHeaderSetXmin(tp.t_data, InvalidTransactionId);
+	HeapTupleSetXmin(&tp, InvalidTransactionId);
+	if (IsToastRelation(relation))
+		ToastTupleHeaderSetXmin(page, &tp);
+	else
+		HeapTupleHeaderSetXmin(page, &tp);
 
 	/* Clear the speculative insertion token too */
 	tp.t_data->t_ctid = tp.t_self;
@@ -5938,6 +6661,8 @@ heap_abort_speculative(Relation relation, ItemPointer tid)
 		XLogRecPtr	recptr;
 
 		xlrec.flags = XLH_DELETE_IS_SUPER;
+		if (IsToastRelation(relation))
+			xlrec.flags |= XLH_DELETE_PAGE_ON_TOAST_RELATION;
 		xlrec.infobits_set = compute_infobits(tp.t_data->t_infomask,
 											  tp.t_data->t_infomask2);
 		xlrec.offnum = ItemPointerGetOffsetNumber(&tp.t_self);
@@ -6267,7 +6992,7 @@ FreezeMultiXactId(MultiXactId multi, uint16 t_infomask,
 	 * individual members might even show that we don't need to keep anything.
 	 */
 	nnewmembers = 0;
-	newmembers = palloc(sizeof(MultiXactMember) * nmembers);
+	newmembers = palloc0(sizeof(MultiXactMember) * nmembers);
 	has_lockers = false;
 	update_xid = InvalidTransactionId;
 	update_committed = false;
@@ -6467,7 +7192,7 @@ FreezeMultiXactId(MultiXactId multi, uint16 t_infomask,
  * The *frz WAL record we output completely removes all old XIDs during REDO.
  */
 bool
-heap_prepare_freeze_tuple(HeapTupleHeader tuple,
+heap_prepare_freeze_tuple(HeapTuple htup,
 						  TransactionId relfrozenxid, TransactionId relminmxid,
 						  TransactionId cutoff_xid, TransactionId cutoff_multi,
 						  xl_heap_freeze_tuple *frz, bool *totally_frozen,
@@ -6479,11 +7204,12 @@ heap_prepare_freeze_tuple(HeapTupleHeader tuple,
 	bool		xmin_frozen;
 	bool		freeze_xmax;
 	TransactionId xid;
+	HeapTupleHeader tuple = htup->t_data;
 
 	frz->frzflags = 0;
 	frz->t_infomask2 = tuple->t_infomask2;
 	frz->t_infomask = tuple->t_infomask;
-	frz->xmax = HeapTupleHeaderGetRawXmax(tuple);
+	frz->xmax = HeapTupleGetRawXmax(htup);
 
 	/*
 	 * Process xmin.  xmin_frozen has two slightly different meanings: in the
@@ -6495,7 +7221,7 @@ heap_prepare_freeze_tuple(HeapTupleHeader tuple,
 	 * handling, since either way the tuple's xmin will be a permanent value
 	 * once we're done with it.
 	 */
-	xid = HeapTupleHeaderGetXmin(tuple);
+	xid = HeapTupleGetXmin(htup);
 	if (!TransactionIdIsNormal(xid))
 		xmin_frozen = true;
 	else
@@ -6537,7 +7263,7 @@ heap_prepare_freeze_tuple(HeapTupleHeader tuple,
 	 *
 	 * Make sure to keep heap_tuple_would_freeze in sync with this.
 	 */
-	xid = HeapTupleHeaderGetRawXmax(tuple);
+	xid = HeapTupleGetRawXmax(htup);
 
 	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
 	{
@@ -6671,7 +7397,7 @@ heap_prepare_freeze_tuple(HeapTupleHeader tuple,
 		}
 	}
 	else if ((tuple->t_infomask & HEAP_XMAX_INVALID) ||
-			 !TransactionIdIsValid(HeapTupleHeaderGetRawXmax(tuple)))
+			 !TransactionIdIsValid(HeapTupleGetRawXmax(htup)))
 	{
 		freeze_xmax = false;
 		xmax_already_frozen = true;
@@ -6767,18 +7493,35 @@ heap_prepare_freeze_tuple(HeapTupleHeader tuple,
  * NB: All code in here must be safe to execute during crash recovery!
  */
 void
-heap_execute_freeze_tuple(HeapTupleHeader tuple, xl_heap_freeze_tuple *frz)
+heap_execute_freeze_tuple(HeapTuple htup, xl_heap_freeze_tuple *frz)
 {
-	HeapTupleHeaderSetXmax(tuple, frz->xmax);
+	HeapTupleHeader tuple = htup->t_data;
+
+	tuple->t_infomask = frz->t_infomask;
+	tuple->t_infomask2 = frz->t_infomask2;
+
+	HeapTupleSetXmax(htup, frz->xmax);
 
 	if (frz->frzflags & XLH_FREEZE_XVAC)
 		HeapTupleHeaderSetXvac(tuple, FrozenTransactionId);
 
 	if (frz->frzflags & XLH_INVALID_XVAC)
 		HeapTupleHeaderSetXvac(tuple, InvalidTransactionId);
+}
 
-	tuple->t_infomask = frz->t_infomask;
-	tuple->t_infomask2 = frz->t_infomask2;
+void
+heap_execute_freeze_tuple_page(Page page, HeapTupleHeader htup,
+							   xl_heap_freeze_tuple *frz, bool is_toast)
+{
+	HeapTupleData tuple;
+
+	tuple.t_data = htup;
+	heap_execute_freeze_tuple(&tuple, frz);
+
+	if (is_toast)
+		ToastTupleHeaderSetXmax(page, &tuple);
+	else
+		HeapTupleHeaderSetXmax(page, &tuple);
 }
 
 /*
@@ -6788,7 +7531,7 @@ heap_execute_freeze_tuple(HeapTupleHeader tuple, xl_heap_freeze_tuple *frz)
  * Useful for callers like CLUSTER that perform their own WAL logging.
  */
 bool
-heap_freeze_tuple(HeapTupleHeader tuple,
+heap_freeze_tuple(HeapTuple tuple,
 				  TransactionId relfrozenxid, TransactionId relminmxid,
 				  TransactionId cutoff_xid, TransactionId cutoff_multi)
 {
@@ -6955,10 +7698,10 @@ MultiXactIdGetUpdateXid(TransactionId xmax, uint16 t_infomask)
  * checking the hint bits.
  */
 TransactionId
-HeapTupleGetUpdateXid(HeapTupleHeader tuple)
+HeapTupleGetUpdateXid(HeapTuple tuple)
 {
-	return MultiXactIdGetUpdateXid(HeapTupleHeaderGetRawXmax(tuple),
-								   tuple->t_infomask);
+	return MultiXactIdGetUpdateXid(HeapTupleGetRawXmax(tuple),
+								   tuple->t_data->t_infomask);
 }
 
 /*
@@ -7184,15 +7927,18 @@ ConditionalMultiXactIdWait(MultiXactId multi, MultiXactStatus status,
  * will eventually require freezing (if tuple isn't removed by pruning first).
  */
 bool
-heap_tuple_needs_eventual_freeze(HeapTupleHeader tuple)
+heap_tuple_needs_eventual_freeze(HeapTuple htup)
 {
 	TransactionId xid;
+	HeapTupleHeader tuple;
+
+	tuple = htup->t_data;
 
 	/*
 	 * If xmin is a normal transaction ID, this tuple is definitely not
 	 * frozen.
 	 */
-	xid = HeapTupleHeaderGetXmin(tuple);
+	xid = HeapTupleGetXmin(htup);
 	if (TransactionIdIsNormal(xid))
 		return true;
 
@@ -7203,13 +7949,13 @@ heap_tuple_needs_eventual_freeze(HeapTupleHeader tuple)
 	{
 		MultiXactId multi;
 
-		multi = HeapTupleHeaderGetRawXmax(tuple);
+		multi = HeapTupleGetRawXmax(htup);
 		if (MultiXactIdIsValid(multi))
 			return true;
 	}
 	else
 	{
-		xid = HeapTupleHeaderGetRawXmax(tuple);
+		xid = HeapTupleGetRawXmax(htup);
 		if (TransactionIdIsNormal(xid))
 			return true;
 	}
@@ -7237,7 +7983,7 @@ heap_tuple_needs_eventual_freeze(HeapTupleHeader tuple)
  * never freeze here, which makes tracking the oldest extant XID/MXID simple.
  */
 bool
-heap_tuple_would_freeze(HeapTupleHeader tuple, TransactionId cutoff_xid,
+heap_tuple_would_freeze(HeapTuple htup, TransactionId cutoff_xid,
 						MultiXactId cutoff_multi,
 						TransactionId *relfrozenxid_out,
 						MultiXactId *relminmxid_out)
@@ -7245,9 +7991,10 @@ heap_tuple_would_freeze(HeapTupleHeader tuple, TransactionId cutoff_xid,
 	TransactionId xid;
 	MultiXactId multi;
 	bool		would_freeze = false;
+	HeapTupleHeader tuple = htup->t_data;
 
 	/* First deal with xmin */
-	xid = HeapTupleHeaderGetXmin(tuple);
+	xid = HeapTupleGetXmin(htup);
 	if (TransactionIdIsNormal(xid))
 	{
 		if (TransactionIdPrecedes(xid, *relfrozenxid_out))
@@ -7260,9 +8007,9 @@ heap_tuple_would_freeze(HeapTupleHeader tuple, TransactionId cutoff_xid,
 	xid = InvalidTransactionId;
 	multi = InvalidMultiXactId;
 	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
-		multi = HeapTupleHeaderGetRawXmax(tuple);
+		multi = HeapTupleGetRawXmax(htup);
 	else
-		xid = HeapTupleHeaderGetRawXmax(tuple);
+		xid = HeapTupleGetRawXmax(htup);
 
 	if (TransactionIdIsNormal(xid))
 	{
@@ -7335,14 +8082,14 @@ heap_tuple_would_freeze(HeapTupleHeader tuple, TransactionId cutoff_xid,
  * with queries.
  */
 void
-HeapTupleHeaderAdvanceLatestRemovedXid(HeapTupleHeader tuple,
+HeapTupleHeaderAdvanceLatestRemovedXid(HeapTuple tuple,
 									   TransactionId *latestRemovedXid)
 {
-	TransactionId xmin = HeapTupleHeaderGetXmin(tuple);
-	TransactionId xmax = HeapTupleHeaderGetUpdateXid(tuple);
-	TransactionId xvac = HeapTupleHeaderGetXvac(tuple);
+	TransactionId xmin = HeapTupleGetXmin(tuple);
+	TransactionId xmax = HeapTupleGetUpdateXidAny(tuple);
+	TransactionId xvac = HeapTupleHeaderGetXvac(tuple->t_data);
 
-	if (tuple->t_infomask & HEAP_MOVED)
+	if (tuple->t_data->t_infomask & HEAP_MOVED)
 	{
 		if (TransactionIdPrecedes(*latestRemovedXid, xvac))
 			*latestRemovedXid = xvac;
@@ -7354,8 +8101,8 @@ HeapTupleHeaderAdvanceLatestRemovedXid(HeapTupleHeader tuple,
 	 *
 	 * Look for a committed hint bit, or if no xmin bit is set, check clog.
 	 */
-	if (HeapTupleHeaderXminCommitted(tuple) ||
-		(!HeapTupleHeaderXminInvalid(tuple) && TransactionIdDidCommit(xmin)))
+	if (HeapTupleHeaderXminCommitted(tuple->t_data) ||
+		(!HeapTupleHeaderXminInvalid(tuple->t_data) && TransactionIdDidCommit(xmin)))
 	{
 		if (xmax != xmin &&
 			TransactionIdFollows(xmax, *latestRemovedXid))
@@ -7705,7 +8452,7 @@ heap_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
 		for (;;)
 		{
 			ItemId		lp;
-			HeapTupleHeader htup;
+			HeapTupleData htup;
 
 			/* Sanity check (pure paranoia) */
 			if (offnum < FirstOffsetNumber)
@@ -7742,16 +8489,18 @@ heap_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
 			if (!ItemIdIsNormal(lp))
 				break;
 
-			htup = (HeapTupleHeader) PageGetItem(page, lp);
+			htup.t_data = (HeapTupleHeader) PageGetItem(page, lp);
+			htup.t_len = ItemIdGetLength(lp);
+			HeapTupleCopyBaseFromPage(&htup, page, IsToastRelation(rel));
 
 			/*
 			 * Check the tuple XMIN against prior XMAX, if any
 			 */
 			if (TransactionIdIsValid(priorXmax) &&
-				!TransactionIdEquals(HeapTupleHeaderGetXmin(htup), priorXmax))
+				!TransactionIdEquals(HeapTupleGetXmin(&htup), priorXmax))
 				break;
 
-			HeapTupleHeaderAdvanceLatestRemovedXid(htup, &latestRemovedXid);
+			HeapTupleHeaderAdvanceLatestRemovedXid(&htup, &latestRemovedXid);
 
 			/*
 			 * If the tuple is not HOT-updated, then we are at the end of this
@@ -7759,13 +8508,13 @@ heap_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
 			 * chain (they get their own index entries) -- just move on to
 			 * next htid from index AM caller.
 			 */
-			if (!HeapTupleHeaderIsHotUpdated(htup))
+			if (!HeapTupleHeaderIsHotUpdated(htup.t_data))
 				break;
 
 			/* Advance to next HOT chain member */
-			Assert(ItemPointerGetBlockNumber(&htup->t_ctid) == blkno);
-			offnum = ItemPointerGetOffsetNumber(&htup->t_ctid);
-			priorXmax = HeapTupleHeaderGetUpdateXid(htup);
+			Assert(ItemPointerGetBlockNumber(&htup.t_data->t_ctid) == blkno);
+			offnum = ItemPointerGetOffsetNumber(&htup.t_data->t_ctid);
+			priorXmax = HeapTupleGetUpdateXidAny(&htup);
 		}
 
 		/* Enable further/final shrinking of deltids for caller */
@@ -8171,6 +8920,9 @@ log_heap_freeze(Relation reln, Buffer buffer, TransactionId cutoff_xid,
 
 	xlrec.cutoff_xid = cutoff_xid;
 	xlrec.ntuples = ntuples;
+	xlrec.flags = 0;
+	if (IsToastRelation(reln))
+		xlrec.flags |= XLH_FREEZE_PAGE_ON_TOAST_RELATION;
 
 	XLogBeginInsert();
 	XLogRegisterData((char *) &xlrec, SizeOfHeapFreezePage);
@@ -8345,13 +9097,13 @@ log_heap_update(Relation reln, Buffer oldbuf,
 
 	/* Prepare WAL data for the old page */
 	xlrec.old_offnum = ItemPointerGetOffsetNumber(&oldtup->t_self);
-	xlrec.old_xmax = HeapTupleHeaderGetRawXmax(oldtup->t_data);
+	xlrec.old_xmax = HeapTupleGetRawXmax(oldtup);
 	xlrec.old_infobits_set = compute_infobits(oldtup->t_data->t_infomask,
 											  oldtup->t_data->t_infomask2);
 
 	/* Prepare WAL data for the new page */
 	xlrec.new_offnum = ItemPointerGetOffsetNumber(&newtup->t_self);
-	xlrec.new_xmax = HeapTupleHeaderGetRawXmax(newtup->t_data);
+	xlrec.new_xmax = HeapTupleGetRawXmax(newtup);
 
 	bufflags = REGBUF_STANDARD;
 	if (init)
@@ -8363,6 +9115,9 @@ log_heap_update(Relation reln, Buffer oldbuf,
 	if (oldbuf != newbuf)
 		XLogRegisterBuffer(1, oldbuf, REGBUF_STANDARD);
 
+	if (info & XLOG_HEAP_INIT_PAGE)
+		XLogRegisterData((char *) &HeapPageGetSpecial(page)->pd_xid_base, sizeof(TransactionId));
+
 	XLogRegisterData((char *) &xlrec, SizeOfHeapUpdate);
 
 	/*
@@ -8475,8 +9230,8 @@ log_heap_new_cid(Relation relation, HeapTuple tup)
 	{
 		Assert(!(hdr->t_infomask & HEAP_XMAX_INVALID));
 		Assert(!HeapTupleHeaderXminInvalid(hdr));
-		xlrec.cmin = HeapTupleHeaderGetCmin(hdr);
-		xlrec.cmax = HeapTupleHeaderGetCmax(hdr);
+		xlrec.cmin = HeapTupleGetCmin(tup);
+		xlrec.cmax = HeapTupleGetCmax(tup);
 		xlrec.combocid = HeapTupleHeaderGetRawCommandId(hdr);
 	}
 	/* No combo CID, so only cmin or cmax can be set by this TX */
@@ -8678,7 +9433,9 @@ heap_xlog_prune(XLogReaderState *record)
 		heap_page_prune_execute(buffer,
 								redirected, nredirected,
 								nowdead, ndead,
-								nowunused, nunused);
+								nowunused, nunused,
+								true,
+								xlrec->flags & XLH_PRUNE_ON_TOAST_RELATION);
 
 		/*
 		 * Note: we don't worry about updating the page's prunability hints.
@@ -8970,7 +9727,8 @@ heap_xlog_freeze_page(XLogReaderState *record)
 			lp = PageGetItemId(page, xlrec_tp->offset); /* offsets are one-based */
 			tuple = (HeapTupleHeader) PageGetItem(page, lp);
 
-			heap_execute_freeze_tuple(tuple, xlrec_tp);
+			heap_execute_freeze_tuple_page(page, tuple, xlrec_tp,
+										   xlrec->flags & XLH_FREEZE_PAGE_ON_TOAST_RELATION);
 		}
 
 		PageSetLSN(page, lsn);
@@ -9041,6 +9799,8 @@ heap_xlog_delete(XLogReaderState *record)
 
 	if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
 	{
+		HeapTupleData tuple;
+
 		page = BufferGetPage(buffer);
 
 		if (PageGetMaxOffsetNumber(page) >= xlrec->offnum)
@@ -9056,14 +9816,29 @@ heap_xlog_delete(XLogReaderState *record)
 		HeapTupleHeaderClearHotUpdated(htup);
 		fix_infomask_from_infobits(xlrec->infobits_set,
 								   &htup->t_infomask, &htup->t_infomask2);
+		tuple.t_data = htup;
+
 		if (!(xlrec->flags & XLH_DELETE_IS_SUPER))
-			HeapTupleHeaderSetXmax(htup, xlrec->xmax);
+		{
+			HeapTupleSetXmax(&tuple, xlrec->xmax);
+			if (xlrec->flags & XLH_DELETE_PAGE_ON_TOAST_RELATION)
+				ToastTupleHeaderSetXmax(page, &tuple);
+			else
+				HeapTupleHeaderSetXmax(page, &tuple);
+		}
 		else
-			HeapTupleHeaderSetXmin(htup, InvalidTransactionId);
+		{
+			HeapTupleSetXmin(&tuple, InvalidTransactionId);
+			if (xlrec->flags & XLH_DELETE_PAGE_ON_TOAST_RELATION)
+				ToastTupleHeaderSetXmin(page, &tuple);
+			else
+				HeapTupleHeaderSetXmin(page, &tuple);
+		}
 		HeapTupleHeaderSetCmax(htup, FirstCommandId, false);
 
 		/* Mark the page as a candidate for pruning */
-		PageSetPrunable(page, XLogRecGetXid(record));
+		PageSetPrunable(page, XLogRecGetXid(record),
+						xlrec->flags & XLH_DELETE_PAGE_ON_TOAST_RELATION);
 
 		if (xlrec->flags & XLH_DELETE_ALL_VISIBLE_CLEARED)
 			PageClearAllVisible(page);
@@ -9084,7 +9859,7 @@ static void
 heap_xlog_insert(XLogReaderState *record)
 {
 	XLogRecPtr	lsn = record->EndRecPtr;
-	xl_heap_insert *xlrec = (xl_heap_insert *) XLogRecGetData(record);
+	xl_heap_insert *xlrec;
 	Buffer		buffer;
 	Page		page;
 	union
@@ -9100,6 +9875,17 @@ heap_xlog_insert(XLogReaderState *record)
 	BlockNumber blkno;
 	ItemPointerData target_tid;
 	XLogRedoAction action;
+	bool		isinit = (XLogRecGetInfo(record) & XLOG_HEAP_INIT_PAGE) != 0;
+	TransactionId pd_xid_base = InvalidTransactionId;
+	Pointer		rec_data = (Pointer) XLogRecGetData(record);
+
+	if (isinit)
+	{
+		pd_xid_base = *((TransactionId *) rec_data);
+		rec_data += sizeof(TransactionId);
+	}
+
+	xlrec = (xl_heap_insert *) rec_data;
 
 	XLogRecGetBlockTag(record, 0, &target_locator, NULL, &blkno);
 	ItemPointerSetBlockNumber(&target_tid, blkno);
@@ -9124,11 +9910,22 @@ heap_xlog_insert(XLogReaderState *record)
 	 * If we inserted the first and only tuple on the page, re-initialize the
 	 * page from scratch.
 	 */
-	if (XLogRecGetInfo(record) & XLOG_HEAP_INIT_PAGE)
+	if (isinit)
 	{
 		buffer = XLogInitBufferForRedo(record, 0);
 		page = BufferGetPage(buffer);
-		PageInit(page, BufferGetPageSize(buffer), 0);
+
+		if (xlrec->flags & XLH_INSERT_ON_TOAST_RELATION)
+		{
+			PageInit(page, BufferGetPageSize(buffer), sizeof(ToastPageSpecialData));
+			ToastPageGetSpecial(page)->pd_xid_base = pd_xid_base;
+		}
+		else
+		{
+			PageInit(page, BufferGetPageSize(buffer), sizeof(HeapPageSpecialData));
+			HeapPageGetSpecial(page)->pd_xid_base = pd_xid_base;
+		}
+
 		action = BLK_NEEDS_REDO;
 	}
 	else
@@ -9137,6 +9934,7 @@ heap_xlog_insert(XLogReaderState *record)
 	{
 		Size		datalen;
 		char	   *data;
+		HeapTupleData tuple;
 
 		page = BufferGetPage(buffer);
 
@@ -9160,7 +9958,12 @@ heap_xlog_insert(XLogReaderState *record)
 		htup->t_infomask2 = xlhdr.t_infomask2;
 		htup->t_infomask = xlhdr.t_infomask;
 		htup->t_hoff = xlhdr.t_hoff;
-		HeapTupleHeaderSetXmin(htup, XLogRecGetXid(record));
+		tuple.t_data = htup;
+		HeapTupleSetXmin(&tuple, XLogRecGetXid(record));
+		if (xlrec->flags & XLH_INSERT_ON_TOAST_RELATION)
+			ToastTupleHeaderSetXmin(page, &tuple);
+		else
+			HeapTupleHeaderSetXmin(page, &tuple);
 		HeapTupleHeaderSetCmin(htup, FirstCommandId);
 		htup->t_ctid = target_tid;
 
@@ -9181,6 +9984,7 @@ heap_xlog_insert(XLogReaderState *record)
 
 		MarkBufferDirty(buffer);
 	}
+
 	if (BufferIsValid(buffer))
 		UnlockReleaseBuffer(buffer);
 
@@ -9220,12 +10024,19 @@ heap_xlog_multi_insert(XLogReaderState *record)
 	int			i;
 	bool		isinit = (XLogRecGetInfo(record) & XLOG_HEAP_INIT_PAGE) != 0;
 	XLogRedoAction action;
+	TransactionId pd_xid_base = InvalidTransactionId;
+	Pointer		rec_data = (Pointer) XLogRecGetData(record);
 
 	/*
 	 * Insertion doesn't overwrite MVCC data, so no conflict processing is
 	 * required.
 	 */
-	xlrec = (xl_heap_multi_insert *) XLogRecGetData(record);
+	if (isinit)
+	{
+		pd_xid_base = *((TransactionId *) rec_data);
+		rec_data += sizeof(TransactionId);
+	}
+	xlrec = (xl_heap_multi_insert *) rec_data;
 
 	XLogRecGetBlockTag(record, 0, &rlocator, NULL, &blkno);
 
@@ -9252,7 +10063,18 @@ heap_xlog_multi_insert(XLogReaderState *record)
 	{
 		buffer = XLogInitBufferForRedo(record, 0);
 		page = BufferGetPage(buffer);
-		PageInit(page, BufferGetPageSize(buffer), 0);
+
+		if (xlrec->flags & XLH_INSERT_ON_TOAST_RELATION)
+		{
+			PageInit(page, BufferGetPageSize(buffer), sizeof(ToastPageSpecialData));
+			ToastPageGetSpecial(page)->pd_xid_base = pd_xid_base;
+		}
+		else
+		{
+			PageInit(page, BufferGetPageSize(buffer), sizeof(HeapPageSpecialData));
+			HeapPageGetSpecial(page)->pd_xid_base = pd_xid_base;
+		}
+
 		action = BLK_NEEDS_REDO;
 	}
 	else
@@ -9273,6 +10095,7 @@ heap_xlog_multi_insert(XLogReaderState *record)
 		{
 			OffsetNumber offnum;
 			xl_multi_insert_tuple *xlhdr;
+			HeapTupleData tuple;
 
 			/*
 			 * If we're reinitializing the page, the tuples are stored in
@@ -9303,7 +10126,9 @@ heap_xlog_multi_insert(XLogReaderState *record)
 			htup->t_infomask2 = xlhdr->t_infomask2;
 			htup->t_infomask = xlhdr->t_infomask;
 			htup->t_hoff = xlhdr->t_hoff;
-			HeapTupleHeaderSetXmin(htup, XLogRecGetXid(record));
+			tuple.t_data = htup;
+			HeapTupleSetXmin(&tuple, XLogRecGetXid(record));
+			HeapTupleHeaderSetXmin(page, &tuple);
 			HeapTupleHeaderSetCmin(htup, FirstCommandId);
 			ItemPointerSetBlockNumber(&htup->t_ctid, blkno);
 			ItemPointerSetOffsetNumber(&htup->t_ctid, offnum);
@@ -9351,7 +10176,7 @@ static void
 heap_xlog_update(XLogReaderState *record, bool hot_update)
 {
 	XLogRecPtr	lsn = record->EndRecPtr;
-	xl_heap_update *xlrec = (xl_heap_update *) XLogRecGetData(record);
+	xl_heap_update *xlrec;
 	RelFileLocator rlocator;
 	BlockNumber oldblk;
 	BlockNumber newblk;
@@ -9376,6 +10201,17 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 	Size		freespace = 0;
 	XLogRedoAction oldaction;
 	XLogRedoAction newaction;
+	bool		isinit = (XLogRecGetInfo(record) & XLOG_HEAP_INIT_PAGE) != 0;
+	TransactionId pd_xid_base = InvalidTransactionId;
+	Pointer		rec_data = (Pointer) XLogRecGetData(record);
+
+	if (isinit)
+	{
+		pd_xid_base = *((TransactionId *) rec_data);
+		rec_data += sizeof(TransactionId);
+	}
+
+	xlrec = (xl_heap_update *) rec_data;
 
 	/* initialize to keep the compiler quiet */
 	oldtup.t_data = NULL;
@@ -9422,6 +10258,8 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 									  &obuffer);
 	if (oldaction == BLK_NEEDS_REDO)
 	{
+		HeapTupleData tuple;
+
 		page = BufferGetPage(obuffer);
 		offnum = xlrec->old_offnum;
 		if (PageGetMaxOffsetNumber(page) >= offnum)
@@ -9434,6 +10272,8 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 
 		oldtup.t_data = htup;
 		oldtup.t_len = ItemIdGetLength(lp);
+		/* Toast tuples are never updated. */
+		HeapTupleCopyBaseFromPage(&oldtup, page, false);
 
 		htup->t_infomask &= ~(HEAP_XMAX_BITS | HEAP_MOVED);
 		htup->t_infomask2 &= ~HEAP_KEYS_UPDATED;
@@ -9443,13 +10283,16 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 			HeapTupleHeaderClearHotUpdated(htup);
 		fix_infomask_from_infobits(xlrec->old_infobits_set, &htup->t_infomask,
 								   &htup->t_infomask2);
-		HeapTupleHeaderSetXmax(htup, xlrec->old_xmax);
+		tuple.t_data = htup;
+		HeapTupleSetXmax(&tuple, xlrec->old_xmax);
+		HeapTupleHeaderSetXmax(page, &tuple);
 		HeapTupleHeaderSetCmax(htup, FirstCommandId, false);
 		/* Set forward chain link in t_ctid */
 		htup->t_ctid = newtid;
 
 		/* Mark the page as a candidate for pruning */
-		PageSetPrunable(page, XLogRecGetXid(record));
+		/* Toast tuples are never updated. */
+		PageSetPrunable(page, XLogRecGetXid(record), false);
 
 		if (xlrec->flags & XLH_UPDATE_OLD_ALL_VISIBLE_CLEARED)
 			PageClearAllVisible(page);
@@ -9466,11 +10309,15 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 		nbuffer = obuffer;
 		newaction = oldaction;
 	}
-	else if (XLogRecGetInfo(record) & XLOG_HEAP_INIT_PAGE)
+	else if (isinit)
 	{
 		nbuffer = XLogInitBufferForRedo(record, 0);
 		page = (Page) BufferGetPage(nbuffer);
-		PageInit(page, BufferGetPageSize(nbuffer), 0);
+
+		/* Toast tuples are never updated. */
+		PageInit(page, BufferGetPageSize(nbuffer), sizeof(HeapPageSpecialData));
+
+		HeapPageGetSpecial(page)->pd_xid_base = pd_xid_base;
 		newaction = BLK_NEEDS_REDO;
 	}
 	else
@@ -9498,6 +10345,7 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 		char	   *recdata_end;
 		Size		datalen;
 		Size		tuplen;
+		HeapTupleData tuple;
 
 		recdata = XLogRecGetBlockData(record, 0, &datalen);
 		recdata_end = recdata + datalen;
@@ -9576,9 +10424,12 @@ heap_xlog_update(XLogReaderState *record, bool hot_update)
 		htup->t_infomask = xlhdr.t_infomask;
 		htup->t_hoff = xlhdr.t_hoff;
 
-		HeapTupleHeaderSetXmin(htup, XLogRecGetXid(record));
+		tuple.t_data = htup;
+		HeapTupleSetXmin(&tuple, XLogRecGetXid(record));
+		HeapTupleHeaderSetXmin(page, &tuple);
 		HeapTupleHeaderSetCmin(htup, FirstCommandId);
-		HeapTupleHeaderSetXmax(htup, xlrec->new_xmax);
+		HeapTupleSetXmax(&tuple, xlrec->new_xmax);
+		HeapTupleHeaderSetXmax(page, &tuple);
 		/* Make sure there is no forward chain link in t_ctid */
 		htup->t_ctid = newtid;
 
@@ -9689,6 +10540,8 @@ heap_xlog_lock(XLogReaderState *record)
 
 	if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
 	{
+		HeapTupleData tuple;
+
 		page = (Page) BufferGetPage(buffer);
 
 		offnum = xlrec->offnum;
@@ -9717,7 +10570,10 @@ heap_xlog_lock(XLogReaderState *record)
 						   BufferGetBlockNumber(buffer),
 						   offnum);
 		}
-		HeapTupleHeaderSetXmax(htup, xlrec->locking_xid);
+
+		tuple.t_data = htup;
+		HeapTupleSetXmax(&tuple, xlrec->locking_xid);
+		HeapTupleHeaderSetXmax(page, &tuple);
 		HeapTupleHeaderSetCmax(htup, FirstCommandId, false);
 		PageSetLSN(page, lsn);
 		MarkBufferDirty(buffer);
@@ -9762,6 +10618,8 @@ heap_xlog_lock_updated(XLogReaderState *record)
 
 	if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
 	{
+		HeapTupleData tuple;
+
 		page = BufferGetPage(buffer);
 
 		offnum = xlrec->offnum;
@@ -9777,7 +10635,9 @@ heap_xlog_lock_updated(XLogReaderState *record)
 		htup->t_infomask2 &= ~HEAP_KEYS_UPDATED;
 		fix_infomask_from_infobits(xlrec->infobits_set, &htup->t_infomask,
 								   &htup->t_infomask2);
-		HeapTupleHeaderSetXmax(htup, xlrec->xmax);
+		tuple.t_data = htup;
+		HeapTupleSetXmax(&tuple, xlrec->xmax);
+		HeapTupleHeaderSetXmax(page, &tuple);
 
 		PageSetLSN(page, lsn);
 		MarkBufferDirty(buffer);
@@ -9827,6 +10687,33 @@ heap_xlog_inplace(XLogReaderState *record)
 		UnlockReleaseBuffer(buffer);
 }
 
+static void
+heap_xlog_base_shift(XLogReaderState *record)
+{
+	XLogRecPtr			lsn = record->EndRecPtr;
+	xl_heap_base_shift *xlrec = (xl_heap_base_shift *) XLogRecGetData(record);
+	Buffer				buffer;
+	Page				page;
+	BlockNumber			blkno;
+	RelFileLocator		target_node;
+
+	XLogRecGetBlockTag(record, 0, &target_node, NULL, &blkno);
+
+	if (XLogReadBufferForRedo(record, 0, &buffer) == BLK_NEEDS_REDO)
+	{
+		page = BufferGetPage(buffer);
+		heap_page_shift_base(NULL, InvalidBuffer, page, xlrec->multi,
+							 xlrec->delta,
+							 xlrec->flags & XLH_BASE_SHIFT_ON_TOAST_RELATION);
+		PageSetLSN(page, lsn);
+		MarkBufferDirty(buffer);
+	}
+
+	if (BufferIsValid(buffer))
+		UnlockReleaseBuffer(buffer);
+}
+
+
 void
 heap_redo(XLogReaderState *record)
 {
@@ -9913,6 +10800,21 @@ heap2_redo(XLogReaderState *record)
 	}
 }
 
+void
+heap3_redo(XLogReaderState *record)
+{
+	uint8		info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
+
+	switch (info & XLOG_HEAP_OPMASK)
+	{
+		case XLOG_HEAP3_BASE_SHIFT:
+			heap_xlog_base_shift(record);
+			break;
+		default:
+			elog(PANIC, "heap3_redo: unknown op code %u", info);
+	}
+}
+
 /*
  * Mask a heap page before performing consistency checks on it.
  */
@@ -9925,6 +10827,10 @@ heap_mask(char *pagedata, BlockNumber blkno)
 	mask_page_lsn_and_checksum(page);
 
 	mask_page_hint_bits(page);
+
+	/* Ignore prune_xid (it's like a hint-bit) */
+	HeapPageSetPruneXid(page, InvalidTransactionId, false);
+
 	mask_unused_space(page);
 
 	for (off = 1; off <= PageGetMaxOffsetNumber(page); off++)
@@ -10040,14 +10946,14 @@ HeapCheckForSerializableConflictOut(bool visible, Relation relation,
 		case HEAPTUPLE_LIVE:
 			if (visible)
 				return;
-			xid = HeapTupleHeaderGetXmin(tuple->t_data);
+			xid = HeapTupleGetXmin(tuple);
 			break;
 		case HEAPTUPLE_RECENTLY_DEAD:
 		case HEAPTUPLE_DELETE_IN_PROGRESS:
 			if (visible)
-				xid = HeapTupleHeaderGetUpdateXid(tuple->t_data);
+				xid = HeapTupleGetUpdateXidAny(tuple);
 			else
-				xid = HeapTupleHeaderGetXmin(tuple->t_data);
+				xid = HeapTupleGetXmin(tuple);
 
 			if (TransactionIdPrecedes(xid, TransactionXmin))
 			{
@@ -10057,7 +10963,7 @@ HeapCheckForSerializableConflictOut(bool visible, Relation relation,
 			}
 			break;
 		case HEAPTUPLE_INSERT_IN_PROGRESS:
-			xid = HeapTupleHeaderGetXmin(tuple->t_data);
+			xid = HeapTupleGetXmin(tuple);
 			break;
 		case HEAPTUPLE_DEAD:
 			Assert(!visible);
diff --git a/src/backend/access/heap/heapam_handler.c b/src/backend/access/heap/heapam_handler.c
index 335abea67c..a7d1a82864 100644
--- a/src/backend/access/heap/heapam_handler.c
+++ b/src/backend/access/heap/heapam_handler.c
@@ -413,7 +413,7 @@ tuple_lock_retry:
 					 * changes in an existing tuple, except to invalid or
 					 * frozen, and neither of those can match priorXmax.)
 					 */
-					if (!TransactionIdEquals(HeapTupleHeaderGetXmin(tuple->t_data),
+					if (!TransactionIdEquals(HeapTupleGetXmin(tuple),
 											 priorXmax))
 					{
 						ReleaseBuffer(buffer);
@@ -473,7 +473,7 @@ tuple_lock_retry:
 					 * variable instead of doing HeapTupleHeaderGetXmin again.
 					 */
 					if (TransactionIdIsCurrentTransactionId(priorXmax) &&
-						HeapTupleHeaderGetCmin(tuple->t_data) >= cid)
+						HeapTupleGetCmin(tuple) >= cid)
 					{
 						tmfd->xmax = priorXmax;
 
@@ -481,7 +481,7 @@ tuple_lock_retry:
 						 * Cmin is the problematic value, so store that. See
 						 * above.
 						 */
-						tmfd->cmax = HeapTupleHeaderGetCmin(tuple->t_data);
+						tmfd->cmax = HeapTupleGetCmin(tuple);
 						ReleaseBuffer(buffer);
 						return TM_SelfModified;
 					}
@@ -507,7 +507,7 @@ tuple_lock_retry:
 				/*
 				 * As above, if xmin isn't what we're expecting, do nothing.
 				 */
-				if (!TransactionIdEquals(HeapTupleHeaderGetXmin(tuple->t_data),
+				if (!TransactionIdEquals(HeapTupleGetXmin(tuple),
 										 priorXmax))
 				{
 					ReleaseBuffer(buffer);
@@ -538,7 +538,7 @@ tuple_lock_retry:
 				/* updated, so look at the updated row */
 				*tid = tuple->t_data->t_ctid;
 				/* updated row should have xmin matching this xmax */
-				priorXmax = HeapTupleHeaderGetUpdateXid(tuple->t_data);
+				priorXmax = HeapTupleGetUpdateXidAny(tuple);
 				ReleaseBuffer(buffer);
 				/* loop back to fetch next in chain */
 			}
@@ -858,7 +858,7 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
 				 * case we had better copy it.
 				 */
 				if (!is_system_catalog &&
-					!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(tuple->t_data)))
+					!TransactionIdIsCurrentTransactionId(HeapTupleGetXmin(tuple)))
 					elog(WARNING, "concurrent insert in progress within table \"%s\"",
 						 RelationGetRelationName(OldHeap));
 				/* treat as live */
@@ -870,7 +870,7 @@ heapam_relation_copy_for_cluster(Relation OldHeap, Relation NewHeap,
 				 * Similar situation to INSERT_IN_PROGRESS case.
 				 */
 				if (!is_system_catalog &&
-					!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetUpdateXid(tuple->t_data)))
+					!TransactionIdIsCurrentTransactionId(HeapTupleGetUpdateXidAny(tuple)))
 					elog(WARNING, "concurrent delete in progress within table \"%s\"",
 						 RelationGetRelationName(OldHeap));
 				/* treat as recently dead */
@@ -1055,6 +1055,7 @@ heapam_scan_analyze_next_tuple(TableScanDesc scan, TransactionId OldestXmin,
 		targtuple->t_tableOid = RelationGetRelid(scan->rs_rd);
 		targtuple->t_data = (HeapTupleHeader) PageGetItem(targpage, itemid);
 		targtuple->t_len = ItemIdGetLength(itemid);
+		HeapTupleCopyBaseFromPage(targtuple, targpage, IsToastRelation(scan->rs_rd));
 
 		switch (HeapTupleSatisfiesVacuum(targtuple, OldestXmin,
 										 hscan->rs_cbuf))
@@ -1090,7 +1091,7 @@ heapam_scan_analyze_next_tuple(TableScanDesc scan, TransactionId OldestXmin,
 				 * numbers we report to the cumulative stats system to make
 				 * this come out right.)
 				 */
-				if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(targtuple->t_data)))
+				if (TransactionIdIsCurrentTransactionId(HeapTupleGetXmin(targtuple)))
 				{
 					sample_it = true;
 					*liverows += 1;
@@ -1121,7 +1122,7 @@ heapam_scan_analyze_next_tuple(TableScanDesc scan, TransactionId OldestXmin,
 				 * but not the post-image.  We also get sane results if the
 				 * concurrent transaction never commits.
 				 */
-				if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetUpdateXid(targtuple->t_data)))
+				if (TransactionIdIsCurrentTransactionId(HeapTupleGetUpdateXidAny(targtuple)))
 					*deadrows += 1;
 				else
 				{
@@ -1370,7 +1371,7 @@ heapam_index_build_range_scan(Relation heapRelation,
 			Page		page = BufferGetPage(hscan->rs_cbuf);
 
 			LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
-			heap_get_root_tuples(page, root_offsets);
+			heap_get_root_tuples(heapRelation, page, root_offsets);
 			LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
 
 			root_blkno = hscan->rs_cblock;
@@ -1463,7 +1464,7 @@ heapam_index_build_range_scan(Relation heapRelation,
 					 * before commit there.  Give a warning if neither case
 					 * applies.
 					 */
-					xwait = HeapTupleHeaderGetXmin(heapTuple->t_data);
+					xwait = HeapTupleGetXmin(heapTuple);
 					if (!TransactionIdIsCurrentTransactionId(xwait))
 					{
 						if (!is_system_catalog)
@@ -1522,7 +1523,7 @@ heapam_index_build_range_scan(Relation heapRelation,
 						break;
 					}
 
-					xwait = HeapTupleHeaderGetUpdateXid(heapTuple->t_data);
+					xwait = HeapTupleGetUpdateXidAny(heapTuple);
 					if (!TransactionIdIsCurrentTransactionId(xwait))
 					{
 						if (!is_system_catalog)
@@ -1667,7 +1668,7 @@ heapam_index_build_range_scan(Relation heapRelation,
 				Page		page = BufferGetPage(hscan->rs_cbuf);
 
 				LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
-				heap_get_root_tuples(page, root_offsets);
+				heap_get_root_tuples(heapRelation, page, root_offsets);
 				LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
 			}
 
@@ -1833,7 +1834,7 @@ heapam_index_validate_scan(Relation heapRelation,
 			Page		page = BufferGetPage(hscan->rs_cbuf);
 
 			LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_SHARE);
-			heap_get_root_tuples(page, root_offsets);
+			heap_get_root_tuples(heapRelation, page, root_offsets);
 			LockBuffer(hscan->rs_cbuf, BUFFER_LOCK_UNLOCK);
 
 			memset(in_index, 0, sizeof(in_index));
@@ -2200,13 +2201,14 @@ heapam_scan_bitmap_next_block(TableScanDesc scan,
 			loctup.t_data = (HeapTupleHeader) PageGetItem((Page) dp, lp);
 			loctup.t_len = ItemIdGetLength(lp);
 			loctup.t_tableOid = scan->rs_rd->rd_id;
+			HeapTupleCopyBaseFromPage(&loctup, dp, IsToastRelation(scan->rs_rd));
 			ItemPointerSet(&loctup.t_self, page, offnum);
 			valid = HeapTupleSatisfiesVisibility(&loctup, snapshot, buffer);
 			if (valid)
 			{
 				hscan->rs_vistuples[ntup++] = offnum;
 				PredicateLockTID(scan->rs_rd, &loctup.t_self, snapshot,
-								 HeapTupleHeaderGetXmin(loctup.t_data));
+								 HeapTupleGetXmin(&loctup));
 			}
 			HeapCheckForSerializableConflictOut(valid, scan->rs_rd, &loctup,
 												buffer, snapshot);
@@ -2245,6 +2247,7 @@ heapam_scan_bitmap_next_tuple(TableScanDesc scan,
 	hscan->rs_ctup.t_data = (HeapTupleHeader) PageGetItem((Page) dp, lp);
 	hscan->rs_ctup.t_len = ItemIdGetLength(lp);
 	hscan->rs_ctup.t_tableOid = scan->rs_rd->rd_id;
+	HeapTupleCopyBaseFromPage(&hscan->rs_ctup, dp, IsToastRelation(scan->rs_rd));
 	ItemPointerSet(&hscan->rs_ctup.t_self, hscan->rs_cblock, targoffset);
 
 	pgstat_count_heap_fetch(scan->rs_rd);
@@ -2385,6 +2388,7 @@ heapam_scan_sample_next_tuple(TableScanDesc scan, SampleScanState *scanstate,
 
 			tuple->t_data = (HeapTupleHeader) PageGetItem(page, itemid);
 			tuple->t_len = ItemIdGetLength(itemid);
+			HeapTupleCopyBaseFromPage(tuple, page, IsToastRelation(scan->rs_rd));
 			ItemPointerSet(&(tuple->t_self), blockno, tupoffset);
 
 
diff --git a/src/backend/access/heap/heapam_visibility.c b/src/backend/access/heap/heapam_visibility.c
index ff0b8a688d..4112a936d1 100644
--- a/src/backend/access/heap/heapam_visibility.c
+++ b/src/backend/access/heap/heapam_visibility.c
@@ -217,7 +217,7 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 				}
 			}
 		}
-		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmin(htup)))
 		{
 			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
 				return true;
@@ -229,7 +229,7 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 			{
 				TransactionId xmax;
 
-				xmax = HeapTupleGetUpdateXid(tuple);
+				xmax = HeapTupleGetUpdateXid(htup);
 
 				/* not LOCKED_ONLY, so it has to have an xmax */
 				Assert(TransactionIdIsValid(xmax));
@@ -241,7 +241,7 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 					return false;
 			}
 
-			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+			if (!TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 			{
 				/* deleting subtransaction must have aborted */
 				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -251,11 +251,11 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 
 			return false;
 		}
-		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsInProgress(HeapTupleGetRawXmin(htup)))
 			return false;
-		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdDidCommit(HeapTupleGetRawXmin(htup)))
 			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
-						HeapTupleHeaderGetRawXmin(tuple));
+						HeapTupleGetRawXmin(htup));
 		else
 		{
 			/* it must have aborted or crashed */
@@ -284,7 +284,7 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
 			return true;
 
-		xmax = HeapTupleGetUpdateXid(tuple);
+		xmax = HeapTupleGetUpdateXid(htup);
 
 		/* not LOCKED_ONLY, so it has to have an xmax */
 		Assert(TransactionIdIsValid(xmax));
@@ -299,17 +299,17 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 		return true;
 	}
 
-	if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+	if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 	{
 		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
 			return true;
 		return false;
 	}
 
-	if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
+	if (TransactionIdIsInProgress(HeapTupleGetRawXmax(htup)))
 		return true;
 
-	if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
+	if (!TransactionIdDidCommit(HeapTupleGetRawXmax(htup)))
 	{
 		/* it must have aborted or crashed */
 		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -327,7 +327,7 @@ HeapTupleSatisfiesSelf(HeapTuple htup, Snapshot snapshot, Buffer buffer)
 	}
 
 	SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
-				HeapTupleHeaderGetRawXmax(tuple));
+				HeapTupleGetRawXmax(htup));
 	return false;
 }
 
@@ -416,7 +416,7 @@ HeapTupleSatisfiesToast(HeapTuple htup, Snapshot snapshot,
 		 * is canceled by super-deleting the tuple.  This also applies to
 		 * TOAST tuples created during speculative insertion.
 		 */
-		else if (!TransactionIdIsValid(HeapTupleHeaderGetXmin(tuple)))
+		else if (!TransactionIdIsValid(HeapTupleGetXmin(htup)))
 			return false;
 	}
 
@@ -506,9 +506,9 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 				}
 			}
 		}
-		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmin(htup)))
 		{
-			if (HeapTupleHeaderGetCmin(tuple) >= curcid)
+			if (HeapTupleGetCmin(htup) >= curcid)
 				return TM_Invisible;	/* inserted after scan started */
 
 			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
@@ -518,7 +518,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 			{
 				TransactionId xmax;
 
-				xmax = HeapTupleHeaderGetRawXmax(tuple);
+				xmax = HeapTupleGetRawXmax(htup);
 
 				/*
 				 * Careful here: even though this tuple was created by our own
@@ -549,7 +549,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 			{
 				TransactionId xmax;
 
-				xmax = HeapTupleGetUpdateXid(tuple);
+				xmax = HeapTupleGetUpdateXid(htup);
 
 				/* not LOCKED_ONLY, so it has to have an xmax */
 				Assert(TransactionIdIsValid(xmax));
@@ -557,21 +557,21 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 				/* deleting subtransaction must have aborted */
 				if (!TransactionIdIsCurrentTransactionId(xmax))
 				{
-					if (MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple),
+					if (MultiXactIdIsRunning(HeapTupleGetRawXmax(htup),
 											 false))
 						return TM_BeingModified;
 					return TM_Ok;
 				}
 				else
 				{
-					if (HeapTupleHeaderGetCmax(tuple) >= curcid)
+					if (HeapTupleGetCmax(htup) >= curcid)
 						return TM_SelfModified; /* updated after scan started */
 					else
 						return TM_Invisible;	/* updated before scan started */
 				}
 			}
 
-			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+			if (!TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 			{
 				/* deleting subtransaction must have aborted */
 				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -579,16 +579,16 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 				return TM_Ok;
 			}
 
-			if (HeapTupleHeaderGetCmax(tuple) >= curcid)
+			if (HeapTupleGetCmax(htup) >= curcid)
 				return TM_SelfModified; /* updated after scan started */
 			else
 				return TM_Invisible;	/* updated before scan started */
 		}
-		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsInProgress(HeapTupleGetRawXmin(htup)))
 			return TM_Invisible;
-		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdDidCommit(HeapTupleGetRawXmin(htup)))
 			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
-						HeapTupleHeaderGetRawXmin(tuple));
+						HeapTupleGetRawXmin(htup));
 		else
 		{
 			/* it must have aborted or crashed */
@@ -622,17 +622,17 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 
 		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
 		{
-			if (MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple), true))
+			if (MultiXactIdIsRunning(HeapTupleGetRawXmax(htup), true))
 				return TM_BeingModified;
 
 			SetHintBits(tuple, buffer, HEAP_XMAX_INVALID, InvalidTransactionId);
 			return TM_Ok;
 		}
 
-		xmax = HeapTupleGetUpdateXid(tuple);
+		xmax = HeapTupleGetUpdateXid(htup);
 		if (!TransactionIdIsValid(xmax))
 		{
-			if (MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple), false))
+			if (MultiXactIdIsRunning(HeapTupleGetRawXmax(htup), false))
 				return TM_BeingModified;
 		}
 
@@ -641,13 +641,13 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 
 		if (TransactionIdIsCurrentTransactionId(xmax))
 		{
-			if (HeapTupleHeaderGetCmax(tuple) >= curcid)
+			if (HeapTupleGetCmax(htup) >= curcid)
 				return TM_SelfModified; /* updated after scan started */
 			else
 				return TM_Invisible;	/* updated before scan started */
 		}
 
-		if (MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple), false))
+		if (MultiXactIdIsRunning(HeapTupleGetRawXmax(htup), false))
 			return TM_BeingModified;
 
 		if (TransactionIdDidCommit(xmax))
@@ -663,7 +663,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 		 * what about the other members?
 		 */
 
-		if (!MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple), false))
+		if (!MultiXactIdIsRunning(HeapTupleGetRawXmax(htup), false))
 		{
 			/*
 			 * There's no member, even just a locker, alive anymore, so we can
@@ -680,20 +680,20 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 		}
 	}
 
-	if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+	if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 	{
 		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
 			return TM_BeingModified;
-		if (HeapTupleHeaderGetCmax(tuple) >= curcid)
+		if (HeapTupleGetCmax(htup) >= curcid)
 			return TM_SelfModified; /* updated after scan started */
 		else
 			return TM_Invisible;	/* updated before scan started */
 	}
 
-	if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
+	if (TransactionIdIsInProgress(HeapTupleGetRawXmax(htup)))
 		return TM_BeingModified;
 
-	if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
+	if (!TransactionIdDidCommit(HeapTupleGetRawXmax(htup)))
 	{
 		/* it must have aborted or crashed */
 		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -711,7 +711,7 @@ HeapTupleSatisfiesUpdate(HeapTuple htup, CommandId curcid,
 	}
 
 	SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
-				HeapTupleHeaderGetRawXmax(tuple));
+				HeapTupleGetRawXmax(htup));
 	if (!ItemPointerEquals(&htup->t_self, &tuple->t_ctid))
 		return TM_Updated;		/* updated by other */
 	else
@@ -794,7 +794,7 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 				}
 			}
 		}
-		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmin(htup)))
 		{
 			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
 				return true;
@@ -806,7 +806,7 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 			{
 				TransactionId xmax;
 
-				xmax = HeapTupleGetUpdateXid(tuple);
+				xmax = HeapTupleGetUpdateXid(htup);
 
 				/* not LOCKED_ONLY, so it has to have an xmax */
 				Assert(TransactionIdIsValid(xmax));
@@ -818,7 +818,7 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 					return false;
 			}
 
-			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+			if (!TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 			{
 				/* deleting subtransaction must have aborted */
 				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -828,7 +828,7 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 
 			return false;
 		}
-		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsInProgress(HeapTupleGetRawXmin(htup)))
 		{
 			/*
 			 * Return the speculative token to caller.  Caller can worry about
@@ -844,13 +844,13 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 				Assert(snapshot->speculativeToken != 0);
 			}
 
-			snapshot->xmin = HeapTupleHeaderGetRawXmin(tuple);
+			snapshot->xmin = HeapTupleGetRawXmin(htup);
 			/* XXX shouldn't we fall through to look at xmax? */
 			return true;		/* in insertion by other */
 		}
-		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdDidCommit(HeapTupleGetRawXmin(htup)))
 			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
-						HeapTupleHeaderGetRawXmin(tuple));
+						HeapTupleGetRawXmin(htup));
 		else
 		{
 			/* it must have aborted or crashed */
@@ -879,7 +879,7 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
 			return true;
 
-		xmax = HeapTupleGetUpdateXid(tuple);
+		xmax = HeapTupleGetUpdateXid(htup);
 
 		/* not LOCKED_ONLY, so it has to have an xmax */
 		Assert(TransactionIdIsValid(xmax));
@@ -897,21 +897,21 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 		return true;
 	}
 
-	if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+	if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 	{
 		if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
 			return true;
 		return false;
 	}
 
-	if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
+	if (TransactionIdIsInProgress(HeapTupleGetRawXmax(htup)))
 	{
 		if (!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask))
-			snapshot->xmax = HeapTupleHeaderGetRawXmax(tuple);
+			snapshot->xmax = HeapTupleGetRawXmax(htup);
 		return true;
 	}
 
-	if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
+	if (!TransactionIdDidCommit(HeapTupleGetRawXmax(htup)))
 	{
 		/* it must have aborted or crashed */
 		SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -929,7 +929,7 @@ HeapTupleSatisfiesDirty(HeapTuple htup, Snapshot snapshot,
 	}
 
 	SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
-				HeapTupleHeaderGetRawXmax(tuple));
+				HeapTupleGetRawXmax(htup));
 	return false;				/* updated by other */
 }
 
@@ -1008,9 +1008,9 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 				}
 			}
 		}
-		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmin(htup)))
 		{
-			if (HeapTupleHeaderGetCmin(tuple) >= snapshot->curcid)
+			if (HeapTupleGetCmin(htup) >= snapshot->curcid)
 				return false;	/* inserted after scan started */
 
 			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
@@ -1023,7 +1023,7 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 			{
 				TransactionId xmax;
 
-				xmax = HeapTupleGetUpdateXid(tuple);
+				xmax = HeapTupleGetUpdateXid(htup);
 
 				/* not LOCKED_ONLY, so it has to have an xmax */
 				Assert(TransactionIdIsValid(xmax));
@@ -1031,13 +1031,13 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 				/* updating subtransaction must have aborted */
 				if (!TransactionIdIsCurrentTransactionId(xmax))
 					return true;
-				else if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
+				else if (HeapTupleGetCmax(htup) >= snapshot->curcid)
 					return true;	/* updated after scan started */
 				else
 					return false;	/* updated before scan started */
 			}
 
-			if (!TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+			if (!TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 			{
 				/* deleting subtransaction must have aborted */
 				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -1045,16 +1045,16 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 				return true;
 			}
 
-			if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
+			if (HeapTupleGetCmax(htup) >= snapshot->curcid)
 				return true;	/* deleted after scan started */
 			else
 				return false;	/* deleted before scan started */
 		}
-		else if (XidInMVCCSnapshot(HeapTupleHeaderGetRawXmin(tuple), snapshot))
+		else if (XidInMVCCSnapshot(HeapTupleGetRawXmin(htup), snapshot))
 			return false;
-		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdDidCommit(HeapTupleGetRawXmin(htup)))
 			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
-						HeapTupleHeaderGetRawXmin(tuple));
+						HeapTupleGetRawXmin(htup));
 		else
 		{
 			/* it must have aborted or crashed */
@@ -1067,7 +1067,7 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 	{
 		/* xmin is committed, but maybe not according to our snapshot */
 		if (!HeapTupleHeaderXminFrozen(tuple) &&
-			XidInMVCCSnapshot(HeapTupleHeaderGetRawXmin(tuple), snapshot))
+			XidInMVCCSnapshot(HeapTupleGetRawXmin(htup), snapshot))
 			return false;		/* treat as still in progress */
 	}
 
@@ -1086,14 +1086,14 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 		/* already checked above */
 		Assert(!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask));
 
-		xmax = HeapTupleGetUpdateXid(tuple);
+		xmax = HeapTupleGetUpdateXid(htup);
 
 		/* not LOCKED_ONLY, so it has to have an xmax */
 		Assert(TransactionIdIsValid(xmax));
 
 		if (TransactionIdIsCurrentTransactionId(xmax))
 		{
-			if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
+			if (HeapTupleGetCmax(htup) >= snapshot->curcid)
 				return true;	/* deleted after scan started */
 			else
 				return false;	/* deleted before scan started */
@@ -1108,18 +1108,18 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 
 	if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
 	{
-		if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmax(tuple)))
+		if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmax(htup)))
 		{
-			if (HeapTupleHeaderGetCmax(tuple) >= snapshot->curcid)
+			if (HeapTupleGetCmax(htup) >= snapshot->curcid)
 				return true;	/* deleted after scan started */
 			else
 				return false;	/* deleted before scan started */
 		}
 
-		if (XidInMVCCSnapshot(HeapTupleHeaderGetRawXmax(tuple), snapshot))
+		if (XidInMVCCSnapshot(HeapTupleGetRawXmax(htup), snapshot))
 			return true;
 
-		if (!TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
+		if (!TransactionIdDidCommit(HeapTupleGetRawXmax(htup)))
 		{
 			/* it must have aborted or crashed */
 			SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
@@ -1129,12 +1129,12 @@ HeapTupleSatisfiesMVCC(HeapTuple htup, Snapshot snapshot,
 
 		/* xmax transaction committed */
 		SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
-					HeapTupleHeaderGetRawXmax(tuple));
+					HeapTupleGetRawXmax(htup));
 	}
 	else
 	{
 		/* xmax is committed, but maybe not according to our snapshot */
-		if (XidInMVCCSnapshot(HeapTupleHeaderGetRawXmax(tuple), snapshot))
+		if (XidInMVCCSnapshot(HeapTupleGetRawXmax(htup), snapshot))
 			return true;		/* treat as still in progress */
 	}
 
@@ -1249,21 +1249,21 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 				return HEAPTUPLE_DEAD;
 			}
 		}
-		else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmin(htup)))
 		{
 			if (tuple->t_infomask & HEAP_XMAX_INVALID)	/* xid invalid */
 				return HEAPTUPLE_INSERT_IN_PROGRESS;
 			/* only locked? run infomask-only check first, for performance */
 			if (HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask) ||
-				HeapTupleHeaderIsOnlyLocked(tuple))
+				HeapTupleIsOnlyLocked(htup))
 				return HEAPTUPLE_INSERT_IN_PROGRESS;
 			/* inserted and then deleted by same xact */
-			if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetUpdateXid(tuple)))
+			if (TransactionIdIsCurrentTransactionId(HeapTupleGetUpdateXidAny(htup)))
 				return HEAPTUPLE_DELETE_IN_PROGRESS;
 			/* deleting subtransaction must have aborted */
 			return HEAPTUPLE_INSERT_IN_PROGRESS;
 		}
-		else if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdIsInProgress(HeapTupleGetRawXmin(htup)))
 		{
 			/*
 			 * It'd be possible to discern between INSERT/DELETE in progress
@@ -1275,9 +1275,9 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 			 */
 			return HEAPTUPLE_INSERT_IN_PROGRESS;
 		}
-		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmin(tuple)))
+		else if (TransactionIdDidCommit(HeapTupleGetRawXmin(htup)))
 			SetHintBits(tuple, buffer, HEAP_XMIN_COMMITTED,
-						HeapTupleHeaderGetRawXmin(tuple));
+						HeapTupleGetRawXmin(htup));
 		else
 		{
 			/*
@@ -1319,14 +1319,14 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 				 * possibly be running; otherwise have to check.
 				 */
 				if (!HEAP_LOCKED_UPGRADED(tuple->t_infomask) &&
-					MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple),
+					MultiXactIdIsRunning(HeapTupleGetRawXmax(htup),
 										 true))
 					return HEAPTUPLE_LIVE;
 				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID, InvalidTransactionId);
 			}
 			else
 			{
-				if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
+				if (TransactionIdIsInProgress(HeapTupleGetRawXmax(htup)))
 					return HEAPTUPLE_LIVE;
 				SetHintBits(tuple, buffer, HEAP_XMAX_INVALID,
 							InvalidTransactionId);
@@ -1344,7 +1344,7 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 
 	if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
 	{
-		TransactionId xmax = HeapTupleGetUpdateXid(tuple);
+		TransactionId xmax = HeapTupleGetUpdateXid(htup);
 
 		/* already checked above */
 		Assert(!HEAP_XMAX_IS_LOCKED_ONLY(tuple->t_infomask));
@@ -1367,7 +1367,7 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 			*dead_after = xmax;
 			return HEAPTUPLE_RECENTLY_DEAD;
 		}
-		else if (!MultiXactIdIsRunning(HeapTupleHeaderGetRawXmax(tuple), false))
+		else if (!MultiXactIdIsRunning(HeapTupleGetRawXmax(htup), false))
 		{
 			/*
 			 * Not in Progress, Not Committed, so either Aborted or crashed.
@@ -1381,11 +1381,11 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 
 	if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED))
 	{
-		if (TransactionIdIsInProgress(HeapTupleHeaderGetRawXmax(tuple)))
+		if (TransactionIdIsInProgress(HeapTupleGetRawXmax(htup)))
 			return HEAPTUPLE_DELETE_IN_PROGRESS;
-		else if (TransactionIdDidCommit(HeapTupleHeaderGetRawXmax(tuple)))
+		else if (TransactionIdDidCommit(HeapTupleGetRawXmax(htup)))
 			SetHintBits(tuple, buffer, HEAP_XMAX_COMMITTED,
-						HeapTupleHeaderGetRawXmax(tuple));
+						HeapTupleGetRawXmax(htup));
 		else
 		{
 			/*
@@ -1407,7 +1407,7 @@ HeapTupleSatisfiesVacuumHorizon(HeapTuple htup, Buffer buffer, TransactionId *de
 	 * Deleter committed, allow caller to check if it was recent enough that
 	 * some open transactions could still see the tuple.
 	 */
-	*dead_after = HeapTupleHeaderGetRawXmax(tuple);
+	*dead_after = HeapTupleGetRawXmax(htup);
 	return HEAPTUPLE_RECENTLY_DEAD;
 }
 
@@ -1503,7 +1503,7 @@ HeapTupleIsSurelyDead(HeapTuple htup, GlobalVisState *vistest)
 
 	/* Deleter committed, so tuple is dead if the XID is old enough. */
 	return GlobalVisTestIsRemovableXid(vistest,
-									   HeapTupleHeaderGetRawXmax(tuple));
+									   HeapTupleGetRawXmax(htup));
 }
 
 /*
@@ -1516,8 +1516,9 @@ HeapTupleIsSurelyDead(HeapTuple htup, GlobalVisState *vistest)
  * at the top of this file.
  */
 bool
-HeapTupleHeaderIsOnlyLocked(HeapTupleHeader tuple)
+HeapTupleIsOnlyLocked(HeapTuple htup)
 {
+	HeapTupleHeader tuple = htup->t_data;
 	TransactionId xmax;
 
 	/* if there's no valid Xmax, then there's obviously no update either */
@@ -1528,7 +1529,7 @@ HeapTupleHeaderIsOnlyLocked(HeapTupleHeader tuple)
 		return true;
 
 	/* invalid xmax means no update */
-	if (!TransactionIdIsValid(HeapTupleHeaderGetRawXmax(tuple)))
+	if (!TransactionIdIsValid(HeapTupleGetRawXmax(htup)))
 		return true;
 
 	/*
@@ -1539,7 +1540,7 @@ HeapTupleHeaderIsOnlyLocked(HeapTupleHeader tuple)
 		return false;
 
 	/* ... but if it's a multi, then perhaps the updating Xid aborted. */
-	xmax = HeapTupleGetUpdateXid(tuple);
+	xmax = HeapTupleGetUpdateXid(htup);
 
 	/* not LOCKED_ONLY, so it has to have an xmax */
 	Assert(TransactionIdIsValid(xmax));
@@ -1587,8 +1588,8 @@ HeapTupleSatisfiesHistoricMVCC(HeapTuple htup, Snapshot snapshot,
 							   Buffer buffer)
 {
 	HeapTupleHeader tuple = htup->t_data;
-	TransactionId xmin = HeapTupleHeaderGetXmin(tuple);
-	TransactionId xmax = HeapTupleHeaderGetRawXmax(tuple);
+	TransactionId xmin = HeapTupleGetXmin(htup);
+	TransactionId xmax = HeapTupleGetRawXmax(htup);
 
 	Assert(ItemPointerIsValid(&htup->t_self));
 	Assert(htup->t_tableOid != InvalidOid);
@@ -1688,7 +1689,7 @@ HeapTupleSatisfiesHistoricMVCC(HeapTuple htup, Snapshot snapshot,
 	 */
 	else if (tuple->t_infomask & HEAP_XMAX_IS_MULTI)
 	{
-		xmax = HeapTupleGetUpdateXid(tuple);
+		xmax = HeapTupleGetUpdateXid(htup);
 	}
 
 	/* check if it's one of our txids, toplevel is also in there */
diff --git a/src/backend/access/heap/heaptoast.c b/src/backend/access/heap/heaptoast.c
index 1575a81b01..252e57cc1d 100644
--- a/src/backend/access/heap/heaptoast.c
+++ b/src/backend/access/heap/heaptoast.c
@@ -307,6 +307,7 @@ heap_toast_insert_or_update(Relation rel, HeapTuple newtup, HeapTuple oldtup,
 		result_tuple->t_len = new_tuple_len;
 		result_tuple->t_self = newtup->t_self;
 		result_tuple->t_tableOid = newtup->t_tableOid;
+		HeapTupleCopyBase(result_tuple, newtup);
 		new_data = (HeapTupleHeader) ((char *) result_tuple + HEAPTUPLESIZE);
 		result_tuple->t_data = new_data;
 
@@ -395,6 +396,7 @@ toast_flatten_tuple(HeapTuple tup, TupleDesc tupleDesc)
 	 */
 	new_tuple->t_self = tup->t_self;
 	new_tuple->t_tableOid = tup->t_tableOid;
+	HeapTupleCopyBase(new_tuple, tup);
 
 	new_tuple->t_data->t_choice = tup->t_data->t_choice;
 	new_tuple->t_data->t_ctid = tup->t_data->t_ctid;
@@ -467,6 +469,7 @@ toast_flatten_tuple_to_datum(HeapTupleHeader tup,
 	ItemPointerSetInvalid(&(tmptup.t_self));
 	tmptup.t_tableOid = InvalidOid;
 	tmptup.t_data = tup;
+	HeapTupleSetZeroBase(&tmptup);
 
 	/*
 	 * Break down the tuple into fields.
diff --git a/src/backend/access/heap/hio.c b/src/backend/access/heap/hio.c
index ae2e2ce37a..14008f6966 100644
--- a/src/backend/access/heap/hio.c
+++ b/src/backend/access/heap/hio.c
@@ -19,6 +19,7 @@
 #include "access/hio.h"
 #include "access/htup_details.h"
 #include "access/visibilitymap.h"
+#include "catalog/catalog.h"
 #include "storage/bufmgr.h"
 #include "storage/freespace.h"
 #include "storage/lmgr.h"
@@ -59,6 +60,19 @@ RelationPutHeapTuple(Relation relation,
 	/* Add the tuple to the page */
 	pageHeader = BufferGetPage(buffer);
 
+	HeapTupleSetXmin(tuple, tuple->t_xmin);
+	if (IsToastRelation(relation))
+	{
+		ToastTupleHeaderSetXmin(pageHeader, tuple);
+		ToastTupleHeaderSetXmax(pageHeader, tuple);
+	}
+	else
+	{
+		HeapTupleHeaderSetXmin(pageHeader, tuple);
+		HeapTupleHeaderSetXmax(pageHeader, tuple);
+	}
+	HeapTupleSetXmax(tuple, tuple->t_xmax);
+
 	offnum = PageAddItem(pageHeader, (Item) tuple->t_data,
 						 tuple->t_len, InvalidOffsetNumber, false, true);
 
@@ -243,7 +257,7 @@ RelationAddExtraBlocks(Relation relation, BulkInsertState bistate)
 
 		/* we'll need this info below */
 		blockNum = BufferGetBlockNumber(buffer);
-		freespace = BufferGetPageSize(buffer) - SizeOfPageHeaderData;
+		freespace = BufferGetPageSize(buffer) - SizeOfPageHeaderData - MAXALIGN(sizeof(HeapPageSpecialData));
 
 		UnlockReleaseBuffer(buffer);
 
@@ -514,6 +528,9 @@ loop:
 		/*
 		 * Now we can check to see if there's enough free space here. If so,
 		 * we're done.
+		 *
+		 * "Double xmax" page is not suitable for any new tuple, since xmin
+		 * can't be set there.
 		 */
 		page = BufferGetPage(buffer);
 
@@ -525,12 +542,23 @@ loop:
 		 */
 		if (PageIsNew(page))
 		{
-			PageInit(page, BufferGetPageSize(buffer), 0);
+			if (IsToastRelation(relation))
+			{
+				PageInit(page, BufferGetPageSize(buffer), sizeof(ToastPageSpecialData));
+				ToastPageGetSpecial(page)->pd_xid_base = RecentXmin - FirstNormalTransactionId;
+			}
+			else
+			{
+				PageInit(page, BufferGetPageSize(buffer), sizeof(HeapPageSpecialData));
+				HeapPageGetSpecial(page)->pd_xid_base = RecentXmin - FirstNormalTransactionId;
+			}
+
 			MarkBufferDirty(buffer);
 		}
 
 		pageFreeSpace = PageGetHeapFreeSpace(page);
-		if (targetFreeSpace <= pageFreeSpace)
+		if (targetFreeSpace <= pageFreeSpace &&
+			!HeapPageIsDoubleXmax(page))
 		{
 			/* use this page as future insert target, too */
 			RelationSetTargetBlock(relation, targetBlock);
@@ -635,7 +663,17 @@ loop:
 			 BufferGetBlockNumber(buffer),
 			 RelationGetRelationName(relation));
 
-	PageInit(page, BufferGetPageSize(buffer), 0);
+	if (IsToastRelation(relation))
+	{
+		PageInit(page, BufferGetPageSize(buffer), sizeof(ToastPageSpecialData));
+		ToastPageGetSpecial(page)->pd_xid_base = RecentXmin - FirstNormalTransactionId;
+	}
+	else
+	{
+		PageInit(page, BufferGetPageSize(buffer), sizeof(HeapPageSpecialData));
+		HeapPageGetSpecial(page)->pd_xid_base = RecentXmin - FirstNormalTransactionId;
+	}
+
 	MarkBufferDirty(buffer);
 
 	/*
diff --git a/src/backend/access/heap/pruneheap.c b/src/backend/access/heap/pruneheap.c
index 9f43bbe25f..7dc8fede3a 100644
--- a/src/backend/access/heap/pruneheap.c
+++ b/src/backend/access/heap/pruneheap.c
@@ -91,6 +91,17 @@ static void heap_prune_record_dead(PruneState *prstate, OffsetNumber offnum);
 static void heap_prune_record_unused(PruneState *prstate, OffsetNumber offnum);
 static void page_verify_redirects(Page page);
 
+static inline bool
+XidFitsPage(Page page, TransactionId xid, bool is_toast)
+{
+	TransactionId	base;
+
+	base = is_toast ? ToastPageGetSpecial(page)->pd_xid_base :
+					  HeapPageGetSpecial(page)->pd_xid_base;
+
+	return xid >= base + FirstNormalTransactionId &&
+		   xid <= base + MaxShortTransactionId;
+}
 
 /*
  * Optionally prune and repair fragmentation in the specified page.
@@ -136,7 +147,8 @@ heap_page_prune_opt(Relation relation, Buffer buffer)
 	 * determining the appropriate horizon is a waste if there's no prune_xid
 	 * (i.e. no updates/deletes left potentially dead tuples around).
 	 */
-	prune_xid = ((PageHeader) page)->pd_prune_xid;
+	prune_xid = HeapPageGetPruneXidNoAssert(page, IsToastRelation(relation));
+
 	if (!TransactionIdIsValid(prune_xid))
 		return;
 
@@ -207,7 +219,7 @@ heap_page_prune_opt(Relation relation, Buffer buffer)
 						nnewlpdead;
 
 			ndeleted = heap_page_prune(relation, buffer, vistest, limited_xmin,
-									   limited_ts, &nnewlpdead, NULL);
+									   limited_ts, &nnewlpdead, NULL, true);
 
 			/*
 			 * Report the number of tuples reclaimed to pgstats.  This is
@@ -268,7 +280,8 @@ heap_page_prune(Relation relation, Buffer buffer,
 				TransactionId old_snap_xmin,
 				TimestampTz old_snap_ts,
 				int *nnewlpdead,
-				OffsetNumber *off_loc)
+				OffsetNumber *off_loc,
+				bool repairFragmentation)
 {
 	int			ndeleted = 0;
 	Page		page = BufferGetPage(buffer);
@@ -339,6 +352,7 @@ heap_page_prune(Relation relation, Buffer buffer,
 		htup = (HeapTupleHeader) PageGetItem(page, itemid);
 		tup.t_data = htup;
 		tup.t_len = ItemIdGetLength(itemid);
+		HeapTupleCopyBaseFromPage(&tup, page, IsToastRelation(relation));
 		ItemPointerSet(&(tup.t_self), blockno, offnum);
 
 		/*
@@ -393,13 +407,17 @@ heap_page_prune(Relation relation, Buffer buffer,
 		heap_page_prune_execute(buffer,
 								prstate.redirected, prstate.nredirected,
 								prstate.nowdead, prstate.ndead,
-								prstate.nowunused, prstate.nunused);
+								prstate.nowunused, prstate.nunused,
+								repairFragmentation,
+								IsToastRelation(relation));
 
 		/*
 		 * Update the page's pd_prune_xid field to either zero, or the lowest
 		 * XID of any soon-prunable tuple.
 		 */
-		((PageHeader) page)->pd_prune_xid = prstate.new_prune_xid;
+		if (XidFitsPage(page, prstate.new_prune_xid, IsToastRelation(relation)))
+			HeapPageSetPruneXid(page, prstate.new_prune_xid,
+								IsToastRelation(relation));
 
 		/*
 		 * Also clear the "page is full" flag, since there's no point in
@@ -421,6 +439,9 @@ heap_page_prune(Relation relation, Buffer buffer,
 			xlrec.latestRemovedXid = prstate.latestRemovedXid;
 			xlrec.nredirected = prstate.nredirected;
 			xlrec.ndead = prstate.ndead;
+			xlrec.flags = 0;
+			if (IsToastRelation(relation))
+				xlrec.flags |= XLH_PRUNE_ON_TOAST_RELATION;
 
 			XLogBeginInsert();
 			XLogRegisterData((char *) &xlrec, SizeOfHeapPrune);
@@ -461,10 +482,12 @@ heap_page_prune(Relation relation, Buffer buffer,
 		 * point in repeating the prune/defrag process until something else
 		 * happens to the page.
 		 */
-		if (((PageHeader) page)->pd_prune_xid != prstate.new_prune_xid ||
+		bool	is_toast = IsToastRelation(relation);
+
+		if (HeapPageGetPruneXid(page, is_toast) != prstate.new_prune_xid ||
 			PageIsFull(page))
 		{
-			((PageHeader) page)->pd_prune_xid = prstate.new_prune_xid;
+			HeapPageSetPruneXid(page, prstate.new_prune_xid, is_toast);
 			PageClearFull(page);
 			MarkBufferDirtyHint(buffer, true);
 		}
@@ -601,6 +624,9 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 	OffsetNumber chainitems[MaxHeapTuplesPerPage];
 	int			nchain = 0,
 				i;
+	HeapTupleData tup;
+
+	tup.t_tableOid = RelationGetRelid(prstate->rel);
 
 	rootlp = PageGetItemId(dp, rootoffnum);
 
@@ -612,6 +638,11 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 		Assert(prstate->htsv[rootoffnum] != -1);
 		htup = (HeapTupleHeader) PageGetItem(dp, rootlp);
 
+		tup.t_data = htup;
+		tup.t_len = ItemIdGetLength(rootlp);
+		ItemPointerSet(&(tup.t_self), BufferGetBlockNumber(buffer), rootoffnum);
+		HeapTupleCopyBaseFromPage(&tup, dp, IsToastRelation(prstate->rel));
+
 		if (HeapTupleHeaderIsHeapOnly(htup))
 		{
 			/*
@@ -636,7 +667,7 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 				!HeapTupleHeaderIsHotUpdated(htup))
 			{
 				heap_prune_record_unused(prstate, rootoffnum);
-				HeapTupleHeaderAdvanceLatestRemovedXid(htup,
+				HeapTupleHeaderAdvanceLatestRemovedXid(&tup,
 													   &prstate->latestRemovedXid);
 				ndeleted++;
 			}
@@ -703,11 +734,16 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 		Assert(prstate->htsv[offnum] != -1);
 		htup = (HeapTupleHeader) PageGetItem(dp, lp);
 
+		tup.t_data = htup;
+		tup.t_len = ItemIdGetLength(lp);
+		HeapTupleCopyBaseFromPage(&tup, dp, IsToastRelation(prstate->rel));
+		ItemPointerSet(&(tup.t_self), BufferGetBlockNumber(buffer), offnum);
+
 		/*
 		 * Check the tuple XMIN against prior XMAX, if any
 		 */
 		if (TransactionIdIsValid(priorXmax) &&
-			!TransactionIdEquals(HeapTupleHeaderGetXmin(htup), priorXmax))
+			!TransactionIdEquals(HeapTupleGetXmin(&tup), priorXmax))
 			break;
 
 		/*
@@ -734,7 +770,7 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 				 * that the page is reconsidered for pruning in future.
 				 */
 				heap_prune_record_prunable(prstate,
-										   HeapTupleHeaderGetUpdateXid(htup));
+										   HeapTupleGetUpdateXidAny(&tup));
 				break;
 
 			case HEAPTUPLE_DELETE_IN_PROGRESS:
@@ -744,7 +780,7 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 				 * that the page is reconsidered for pruning in future.
 				 */
 				heap_prune_record_prunable(prstate,
-										   HeapTupleHeaderGetUpdateXid(htup));
+										   HeapTupleGetUpdateXidAny(&tup));
 				break;
 
 			case HEAPTUPLE_LIVE:
@@ -773,7 +809,7 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 		if (tupdead)
 		{
 			latestdead = offnum;
-			HeapTupleHeaderAdvanceLatestRemovedXid(htup,
+			HeapTupleHeaderAdvanceLatestRemovedXid(&tup,
 												   &prstate->latestRemovedXid);
 		}
 		else if (!recent_dead)
@@ -795,7 +831,7 @@ heap_prune_chain(Buffer buffer, OffsetNumber rootoffnum, PruneState *prstate)
 		Assert(ItemPointerGetBlockNumber(&htup->t_ctid) ==
 			   BufferGetBlockNumber(buffer));
 		offnum = ItemPointerGetOffsetNumber(&htup->t_ctid);
-		priorXmax = HeapTupleHeaderGetUpdateXid(htup);
+		priorXmax = HeapTupleGetUpdateXidAny(&tup);
 	}
 
 	/*
@@ -912,7 +948,9 @@ void
 heap_page_prune_execute(Buffer buffer,
 						OffsetNumber *redirected, int nredirected,
 						OffsetNumber *nowdead, int ndead,
-						OffsetNumber *nowunused, int nunused)
+						OffsetNumber *nowunused, int nunused,
+						bool repairFragmentation,
+						bool is_toast)
 {
 	Page		page = (Page) BufferGetPage(buffer);
 	OffsetNumber *offnum;
@@ -1036,7 +1074,8 @@ heap_page_prune_execute(Buffer buffer,
 	 * Finally, repair any fragmentation, and update the page's hint bit about
 	 * whether it has free pointers.
 	 */
-	PageRepairFragmentation(page);
+	if (repairFragmentation)
+		PageRepairFragmentation(page, is_toast);
 
 	/*
 	 * Now that the page has been modified, assert that redirect items still
@@ -1108,7 +1147,7 @@ page_verify_redirects(Page page)
  * and reused by a completely unrelated tuple.
  */
 void
-heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
+heap_get_root_tuples(Relation relation, Page page, OffsetNumber *root_offsets)
 {
 	OffsetNumber offnum,
 				maxoff;
@@ -1123,6 +1162,7 @@ heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
 		HeapTupleHeader htup;
 		OffsetNumber nextoffnum;
 		TransactionId priorXmax;
+		HeapTupleData tup;
 
 		/* skip unused and dead items */
 		if (!ItemIdIsUsed(lp) || ItemIdIsDead(lp))
@@ -1131,6 +1171,8 @@ heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
 		if (ItemIdIsNormal(lp))
 		{
 			htup = (HeapTupleHeader) PageGetItem(page, lp);
+			tup.t_data = htup;
+			HeapTupleCopyBaseFromPage(&tup, page, IsToastRelation(relation));
 
 			/*
 			 * Check if this tuple is part of a HOT-chain rooted at some other
@@ -1152,7 +1194,7 @@ heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
 
 			/* Set up to scan the HOT-chain */
 			nextoffnum = ItemPointerGetOffsetNumber(&htup->t_ctid);
-			priorXmax = HeapTupleHeaderGetUpdateXid(htup);
+			priorXmax = HeapTupleGetUpdateXidAny(&tup);
 		}
 		else
 		{
@@ -1191,9 +1233,11 @@ heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
 				break;
 
 			htup = (HeapTupleHeader) PageGetItem(page, lp);
+			tup.t_data = htup;
+			HeapTupleCopyBaseFromPage(&tup, page, IsToastRelation(relation));
 
 			if (TransactionIdIsValid(priorXmax) &&
-				!TransactionIdEquals(priorXmax, HeapTupleHeaderGetXmin(htup)))
+				!TransactionIdEquals(priorXmax, HeapTupleGetXmin(&tup)))
 				break;
 
 			/* Remember the root line pointer for this item */
@@ -1207,7 +1251,7 @@ heap_get_root_tuples(Page page, OffsetNumber *root_offsets)
 			Assert(!HeapTupleHeaderIndicatesMovedPartitions(htup));
 
 			nextoffnum = ItemPointerGetOffsetNumber(&htup->t_ctid);
-			priorXmax = HeapTupleHeaderGetUpdateXid(htup);
+			priorXmax = HeapTupleGetUpdateXidAny(&tup);
 		}
 	}
 }
diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index 197f06b5ec..a132fa1425 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -379,6 +379,7 @@ rewrite_heap_tuple(RewriteState state,
 		   &old_tuple->t_data->t_choice.t_heap,
 		   sizeof(HeapTupleFields));
 
+	HeapTupleCopyBase(new_tuple, old_tuple);
 	new_tuple->t_data->t_infomask &= ~HEAP_XACT_MASK;
 	new_tuple->t_data->t_infomask2 &= ~HEAP2_XACT_MASK;
 	new_tuple->t_data->t_infomask |=
@@ -388,7 +389,7 @@ rewrite_heap_tuple(RewriteState state,
 	 * While we have our hands on the tuple, we may as well freeze any
 	 * eligible xmin or xmax, so that future VACUUM effort can be saved.
 	 */
-	heap_freeze_tuple(new_tuple->t_data,
+	heap_freeze_tuple(new_tuple,
 					  state->rs_old_rel->rd_rel->relfrozenxid,
 					  state->rs_old_rel->rd_rel->relminmxid,
 					  state->rs_freeze_xid,
@@ -404,7 +405,7 @@ rewrite_heap_tuple(RewriteState state,
 	 * If the tuple has been updated, check the old-to-new mapping hash table.
 	 */
 	if (!((old_tuple->t_data->t_infomask & HEAP_XMAX_INVALID) ||
-		  HeapTupleHeaderIsOnlyLocked(old_tuple->t_data)) &&
+		  HeapTupleIsOnlyLocked(old_tuple)) &&
 		!HeapTupleHeaderIndicatesMovedPartitions(old_tuple->t_data) &&
 		!(ItemPointerEquals(&(old_tuple->t_self),
 							&(old_tuple->t_data->t_ctid))))
@@ -412,7 +413,7 @@ rewrite_heap_tuple(RewriteState state,
 		OldToNewMapping mapping;
 
 		memset(&hashkey, 0, sizeof(hashkey));
-		hashkey.xmin = HeapTupleHeaderGetUpdateXid(old_tuple->t_data);
+		hashkey.xmin = HeapTupleGetUpdateXidAny(old_tuple);
 		hashkey.tid = old_tuple->t_data->t_ctid;
 
 		mapping = (OldToNewMapping)
@@ -485,7 +486,7 @@ rewrite_heap_tuple(RewriteState state,
 		 * RECENTLY_DEAD if and only if the xmin is not before OldestXmin.
 		 */
 		if ((new_tuple->t_data->t_infomask & HEAP_UPDATED) &&
-			!TransactionIdPrecedes(HeapTupleHeaderGetXmin(new_tuple->t_data),
+			!TransactionIdPrecedes(HeapTupleGetXmin(new_tuple),
 								   state->rs_oldest_xmin))
 		{
 			/*
@@ -494,7 +495,7 @@ rewrite_heap_tuple(RewriteState state,
 			UnresolvedTup unresolved;
 
 			memset(&hashkey, 0, sizeof(hashkey));
-			hashkey.xmin = HeapTupleHeaderGetXmin(new_tuple->t_data);
+			hashkey.xmin = HeapTupleGetXmin(new_tuple);
 			hashkey.tid = old_tid;
 
 			unresolved = hash_search(state->rs_unresolved_tups, &hashkey,
@@ -582,7 +583,7 @@ rewrite_heap_dead_tuple(RewriteState state, HeapTuple old_tuple)
 	bool		found;
 
 	memset(&hashkey, 0, sizeof(hashkey));
-	hashkey.xmin = HeapTupleHeaderGetXmin(old_tuple->t_data);
+	hashkey.xmin = HeapTupleGetXmin(old_tuple);
 	hashkey.tid = old_tuple->t_self;
 
 	unresolved = hash_search(state->rs_unresolved_tups, &hashkey,
@@ -618,6 +619,8 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
 	Size		len;
 	OffsetNumber newoff;
 	HeapTuple	heaptup;
+	TransactionId xmin;
+	bool        immutable_tuple;
 
 	/*
 	 * If the new tuple is too big for storage or contains already toasted
@@ -652,9 +655,19 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
 	len = MAXALIGN(heaptup->t_len); /* be conservative */
 
 	/*
-	 * If we're gonna fail for oversize tuple, do it right away
+	 * Due to update to 64-xid maximum plain tuple size was decreased due to adding
+	 * PageSpecial to a heap page. Pages with tuple that became too large to fit,
+	 * should remain in Double Xmax format (read only). Inserting plain tuples with
+	 * size over new MaxHeapTupleSizs is prohibited anyway, but vaccum full will
+	 * transfer this page to a rebuild relation unmodified.
 	 */
-	if (len > MaxHeapTupleSize)
+	immutable_tuple = len <= MaxHeapTupleSize_32 && len > MaxHeapTupleSize;
+
+	/*
+	 * If we're gonna fail for oversize tuple, do it right away. But allow to process
+	 * immutable_tuple (see above).
+	 */
+	if (len > MaxHeapTupleSize && !immutable_tuple)
 		ereport(ERROR,
 				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
 				 errmsg("row is too big: size %zu, maximum size %zu",
@@ -703,10 +716,42 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
 	if (!state->rs_buffer_valid)
 	{
 		/* Initialize a new empty page */
-		PageInit(page, BLCKSZ, 0);
+		if (immutable_tuple)
+			/* Initialize DoubleXmax page */
+			PageInit(page, BLCKSZ, 0);
+		else
+		{
+			Size	special_size;
+
+			special_size = IsToastRelation(state->rs_new_rel) ?
+								sizeof(ToastPageSpecialData) :
+								sizeof(HeapPageSpecialData);
+			PageInit(page, BLCKSZ, special_size);
+		}
 		state->rs_buffer_valid = true;
 	}
 
+	rewrite_page_prepare_for_xid(page, heaptup,
+								 IsToastRelation(state->rs_new_rel));
+
+	/*
+	 * Tuple with HEAP_XMIN_FROZEN in t_infomask should have xmin set
+	 * to FrozenTransactionId to avoid these tuples be treated like normal.
+	 */
+	xmin = HeapTupleGetXmin(heaptup);
+	HeapTupleSetXmin(heaptup, xmin);
+
+	/*
+	 * Tuples on DoubleXmax page could not appear modified after they had been
+	 * frozen by pg_upgrade. Just check this to be safe.
+	 */
+	Assert(!immutable_tuple || xmin == FrozenTransactionId);
+
+	if (!immutable_tuple)
+		HeapTupleHeaderSetXmin(page, heaptup);
+
+	HeapTupleHeaderSetXmax(page, heaptup);
+
 	/* And now we can insert the tuple into the page */
 	newoff = PageAddItem(page, (Item) heaptup->t_data, heaptup->t_len,
 						 InvalidOffsetNumber, false, true);
@@ -999,7 +1044,10 @@ logical_rewrite_log_mapping(RewriteState state, TransactionId xid,
 				 "pg_logical/mappings/" LOGICAL_REWRITE_FORMAT,
 				 dboid, relid,
 				 LSN_FORMAT_ARGS(state->rs_begin_lsn),
-				 xid, GetCurrentTransactionId());
+				 (uint32) (xid >> 32),
+				 (uint32) xid,
+				 (uint32) (GetCurrentTransactionId() >> 32),
+				 (uint32) GetCurrentTransactionId());
 
 		dlist_init(&src->mappings);
 		src->num_mappings = 0;
@@ -1048,9 +1096,9 @@ logical_rewrite_heap_tuple(RewriteState state, ItemPointerData old_tid,
 	if (!state->rs_logical_rewrite)
 		return;
 
-	xmin = HeapTupleHeaderGetXmin(new_tuple->t_data);
+	xmin = HeapTupleGetXmin(new_tuple);
 	/* use *GetUpdateXid to correctly deal with multixacts */
-	xmax = HeapTupleHeaderGetUpdateXid(new_tuple->t_data);
+	xmax = HeapTupleGetUpdateXidAny(new_tuple);
 
 	/*
 	 * Log the mapping iff the tuple has been created recently.
@@ -1121,7 +1169,10 @@ heap_xlog_logical_rewrite(XLogReaderState *r)
 			 "pg_logical/mappings/" LOGICAL_REWRITE_FORMAT,
 			 xlrec->mapped_db, xlrec->mapped_rel,
 			 LSN_FORMAT_ARGS(xlrec->start_lsn),
-			 xlrec->mapped_xid, XLogRecGetXid(r));
+			 (uint32) (xlrec->mapped_xid >> 32),
+			 (uint32) xlrec->mapped_xid,
+			 (uint32) (XLogRecGetXid(r) >> 32),
+			 (uint32) XLogRecGetXid(r));
 
 	fd = OpenTransientFile(path,
 						   O_CREAT | O_WRONLY | PG_BINARY);
@@ -1217,10 +1268,12 @@ CheckPointLogicalRewriteHeap(void)
 		Oid			dboid;
 		Oid			relid;
 		XLogRecPtr	lsn;
-		TransactionId rewrite_xid;
-		TransactionId create_xid;
-		uint32		hi,
-					lo;
+		uint32		lsn_hi,
+					lsn_lo,
+					rewrite_xid_hi,
+					rewrite_xid_lo,
+					create_xid_hi,
+					create_xid_lo;
 
 		if (strcmp(mapping_de->d_name, ".") == 0 ||
 			strcmp(mapping_de->d_name, "..") == 0)
@@ -1235,10 +1288,12 @@ CheckPointLogicalRewriteHeap(void)
 			continue;
 
 		if (sscanf(mapping_de->d_name, LOGICAL_REWRITE_FORMAT,
-				   &dboid, &relid, &hi, &lo, &rewrite_xid, &create_xid) != 6)
+				   &dboid, &relid, &lsn_hi, &lsn_lo,
+				   &rewrite_xid_hi, &rewrite_xid_lo,
+				   &create_xid_hi, &create_xid_lo) != 8)
 			elog(ERROR, "could not parse filename \"%s\"", mapping_de->d_name);
 
-		lsn = ((uint64) hi) << 32 | lo;
+		lsn = ((uint64) lsn_hi) << 32 | lsn_lo;
 
 		if (lsn < cutoff || cutoff == InvalidXLogRecPtr)
 		{
diff --git a/src/backend/access/heap/vacuumlazy.c b/src/backend/access/heap/vacuumlazy.c
index 1171616ba6..fb8b367cf7 100644
--- a/src/backend/access/heap/vacuumlazy.c
+++ b/src/backend/access/heap/vacuumlazy.c
@@ -46,6 +46,7 @@
 #include "access/xlog.h"
 #include "access/xloginsert.h"
 #include "catalog/index.h"
+#include "catalog/catalog.h"
 #include "catalog/storage.h"
 #include "commands/dbcommands.h"
 #include "commands/progress.h"
@@ -265,7 +266,6 @@ static bool lazy_vacuum_all_indexes(LVRelState *vacrel);
 static void lazy_vacuum_heap_rel(LVRelState *vacrel);
 static int	lazy_vacuum_heap_page(LVRelState *vacrel, BlockNumber blkno,
 								  Buffer buffer, int index, Buffer *vmbuffer);
-static bool lazy_check_wraparound_failsafe(LVRelState *vacrel);
 static void lazy_cleanup_all_indexes(LVRelState *vacrel);
 static IndexBulkDeleteResult *lazy_vacuum_one_index(Relation indrel,
 													IndexBulkDeleteResult *istat,
@@ -524,7 +524,6 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 	 * ensure that parallel VACUUM won't be attempted at all when relfrozenxid
 	 * is already dangerously old.)
 	 */
-	lazy_check_wraparound_failsafe(vacrel);
 	dead_items_alloc(vacrel, params->nworkers);
 
 	/*
@@ -641,7 +640,7 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 			WalUsage	walusage;
 			StringInfoData buf;
 			char	   *msgfmt;
-			int32		diff;
+			int64		diff;
 			int64		PageHitOp = VacuumPageHit - StartPageHit,
 						PageMissOp = VacuumPageMiss - StartPageMiss,
 						PageDirtyOp = VacuumPageDirty - StartPageDirty;
@@ -694,32 +693,35 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
 							 orig_rel_pages == 0 ? 100.0 :
 							 100.0 * vacrel->scanned_pages / orig_rel_pages);
 			appendStringInfo(&buf,
-							 _("tuples: %lld removed, %lld remain, %lld are dead but not yet removable\n"),
+							 _("tuples: %lld removed, %lld remain, %lld are dead but not yet removable, oldest xmin: %llu\n"),
 							 (long long) vacrel->tuples_deleted,
 							 (long long) vacrel->new_rel_tuples,
-							 (long long) vacrel->recently_dead_tuples);
+							 (long long) vacrel->recently_dead_tuples,
+							 (unsigned long long) OldestXmin);
 			if (vacrel->missed_dead_tuples > 0)
 				appendStringInfo(&buf,
 								 _("tuples missed: %lld dead from %u pages not removed due to cleanup lock contention\n"),
 								 (long long) vacrel->missed_dead_tuples,
 								 vacrel->missed_dead_pages);
-			diff = (int32) (ReadNextTransactionId() - OldestXmin);
+			diff = (int64) (ReadNextTransactionId() - OldestXmin);
 			appendStringInfo(&buf,
-							 _("removable cutoff: %llu, which was %d XIDs old when operation ended\n"),
-							 (unsigned long long) OldestXmin, diff);
+							 _("removable cutoff: %llu, which was %lld XIDs old when operation ended\n"),
+							 (unsigned long long) OldestXmin, (long long) diff);
 			if (frozenxid_updated)
 			{
-				diff = (int32) (vacrel->NewRelfrozenXid - vacrel->relfrozenxid);
+				diff = (int64) (vacrel->NewRelfrozenXid - vacrel->relfrozenxid);
 				appendStringInfo(&buf,
-								 _("new relfrozenxid: %llu, which is %d XIDs ahead of previous value\n"),
-								 (unsigned long long) vacrel->NewRelfrozenXid, diff);
+								 _("new relfrozenxid: %llu, which is %lld XIDs ahead of previous value\n"),
+								 (unsigned long long) vacrel->NewRelfrozenXid,
+								 (long long) diff);
 			}
 			if (minmulti_updated)
 			{
-				diff = (int32) (vacrel->NewRelminMxid - vacrel->relminmxid);
+				diff = (int64) (vacrel->NewRelminMxid - vacrel->relminmxid);
 				appendStringInfo(&buf,
-								 _("new relminmxid: %llu, which is %d MXIDs ahead of previous value\n"),
-								 (unsigned long long) vacrel->NewRelminMxid, diff);
+								 _("new relminmxid: %llu, which is %lld MXIDs ahead of previous value\n"),
+								 (unsigned long long) vacrel->NewRelminMxid,
+								 (long long) diff);
 			}
 			if (vacrel->do_index_vacuuming)
 			{
@@ -923,7 +925,6 @@ lazy_scan_heap(LVRelState *vacrel)
 		 */
 		if (blkno - next_failsafe_block >= FAILSAFE_EVERY_PAGES)
 		{
-			lazy_check_wraparound_failsafe(vacrel);
 			next_failsafe_block = blkno;
 		}
 
@@ -1443,7 +1444,14 @@ lazy_scan_new_or_empty(LVRelState *vacrel, Buffer buf, BlockNumber blkno,
 
 		if (GetRecordedFreeSpace(vacrel->rel, blkno) == 0)
 		{
-			freespace = BLCKSZ - SizeOfPageHeaderData;
+			Size		special_size;
+
+			special_size = IsToastRelation(vacrel->rel) ?
+								sizeof(ToastPageSpecialData) :
+								sizeof(HeapPageSpecialData);
+			freespace = BufferGetPageSize(buf)
+						- SizeOfPageHeaderData
+						- special_size;
 
 			RecordPageWithFreeSpace(vacrel->rel, blkno, freespace);
 		}
@@ -1547,6 +1555,7 @@ lazy_scan_prune(LVRelState *vacrel,
 				maxoff;
 	ItemId		itemid;
 	HeapTupleData tuple;
+	HeapTupleHeader htup;
 	HTSV_Result res;
 	int			tuples_deleted,
 				lpdead_items,
@@ -1589,7 +1598,7 @@ retry:
 	 */
 	tuples_deleted = heap_page_prune(rel, buf, vacrel->vistest,
 									 InvalidTransactionId, 0, &nnewlpdead,
-									 &vacrel->offnum);
+									 &vacrel->offnum, true);
 
 	/*
 	 * Now scan the page to collect LP_DEAD items and check for tuples
@@ -1655,6 +1664,7 @@ retry:
 		tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
 		tuple.t_len = ItemIdGetLength(itemid);
 		tuple.t_tableOid = RelationGetRelid(rel);
+		HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(rel));
 
 		/*
 		 * DEAD tuples are almost always pruned into LP_DEAD line pointers by
@@ -1718,7 +1728,7 @@ retry:
 					 * The inserter definitely committed. But is it old enough
 					 * that everyone sees it as committed?
 					 */
-					xmin = HeapTupleHeaderGetXmin(tuple.t_data);
+					xmin = HeapTupleGetXmin(&tuple);
 					if (!TransactionIdPrecedes(xmin, vacrel->OldestXmin))
 					{
 						prunestate->all_visible = false;
@@ -1774,7 +1784,7 @@ retry:
 		 * now.
 		 */
 		prunestate->hastup = true;	/* page makes rel truncation unsafe */
-		if (heap_prepare_freeze_tuple(tuple.t_data,
+		if (heap_prepare_freeze_tuple(&tuple,
 									  vacrel->relfrozenxid,
 									  vacrel->relminmxid,
 									  vacrel->FreezeLimit,
@@ -1828,12 +1838,10 @@ retry:
 		/* execute collected freezes */
 		for (int i = 0; i < nfrozen; i++)
 		{
-			HeapTupleHeader htup;
-
 			itemid = PageGetItemId(page, frozen[i].offset);
 			htup = (HeapTupleHeader) PageGetItem(page, itemid);
-
-			heap_execute_freeze_tuple(htup, &frozen[i]);
+			heap_execute_freeze_tuple_page(page, htup, &frozen[i],
+										   IsToastRelation(vacrel->rel));
 		}
 
 		/* Now WAL-log freezing if necessary */
@@ -1952,7 +1960,6 @@ lazy_scan_noprune(LVRelState *vacrel,
 				live_tuples,
 				recently_dead_tuples,
 				missed_dead_tuples;
-	HeapTupleHeader tupleheader;
 	TransactionId NewRelfrozenXid = vacrel->NewRelfrozenXid;
 	MultiXactId NewRelminMxid = vacrel->NewRelminMxid;
 	OffsetNumber deadoffsets[MaxHeapTuplesPerPage];
@@ -1998,8 +2005,13 @@ lazy_scan_noprune(LVRelState *vacrel,
 		}
 
 		*hastup = true;			/* page prevents rel truncation */
-		tupleheader = (HeapTupleHeader) PageGetItem(page, itemid);
-		if (heap_tuple_would_freeze(tupleheader,
+		ItemPointerSet(&(tuple.t_self), blkno, offnum);
+		tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
+		tuple.t_len = ItemIdGetLength(itemid);
+		tuple.t_tableOid = RelationGetRelid(vacrel->rel);
+		HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(vacrel->rel));
+
+		if (heap_tuple_would_freeze(&tuple,
 									vacrel->FreezeLimit,
 									vacrel->MultiXactCutoff,
 									&NewRelfrozenXid, &NewRelminMxid))
@@ -2032,11 +2044,6 @@ lazy_scan_noprune(LVRelState *vacrel,
 			 */
 		}
 
-		ItemPointerSet(&(tuple.t_self), blkno, offnum);
-		tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
-		tuple.t_len = ItemIdGetLength(itemid);
-		tuple.t_tableOid = RelationGetRelid(vacrel->rel);
-
 		switch (HeapTupleSatisfiesVacuum(&tuple, vacrel->OldestXmin, buf))
 		{
 			case HEAPTUPLE_DELETE_IN_PROGRESS:
@@ -2306,13 +2313,6 @@ lazy_vacuum_all_indexes(LVRelState *vacrel)
 	Assert(vacrel->do_index_vacuuming);
 	Assert(vacrel->do_index_cleanup);
 
-	/* Precheck for XID wraparound emergencies */
-	if (lazy_check_wraparound_failsafe(vacrel))
-	{
-		/* Wraparound emergency -- don't even start an index scan */
-		return false;
-	}
-
 	/* Report that we are now vacuuming indexes */
 	pgstat_progress_update_param(PROGRESS_VACUUM_PHASE,
 								 PROGRESS_VACUUM_PHASE_VACUUM_INDEX);
@@ -2327,13 +2327,6 @@ lazy_vacuum_all_indexes(LVRelState *vacrel)
 			vacrel->indstats[idx] =
 				lazy_vacuum_one_index(indrel, istat, vacrel->old_live_tuples,
 									  vacrel);
-
-			if (lazy_check_wraparound_failsafe(vacrel))
-			{
-				/* Wraparound emergency -- end current index scan */
-				allindexes = false;
-				break;
-			}
 		}
 	}
 	else
@@ -2341,13 +2334,6 @@ lazy_vacuum_all_indexes(LVRelState *vacrel)
 		/* Outsource everything to parallel variant */
 		parallel_vacuum_bulkdel_all_indexes(vacrel->pvs, vacrel->old_live_tuples,
 											vacrel->num_index_scans);
-
-		/*
-		 * Do a postcheck to consider applying wraparound failsafe now.  Note
-		 * that parallel VACUUM only gets the precheck and this postcheck.
-		 */
-		if (lazy_check_wraparound_failsafe(vacrel))
-			allindexes = false;
 	}
 
 	/*
@@ -2593,58 +2579,6 @@ lazy_vacuum_heap_page(LVRelState *vacrel, BlockNumber blkno, Buffer buffer,
 	return index;
 }
 
-/*
- * Trigger the failsafe to avoid wraparound failure when vacrel table has a
- * relfrozenxid and/or relminmxid that is dangerously far in the past.
- * Triggering the failsafe makes the ongoing VACUUM bypass any further index
- * vacuuming and heap vacuuming.  Truncating the heap is also bypassed.
- *
- * Any remaining work (work that VACUUM cannot just bypass) is typically sped
- * up when the failsafe triggers.  VACUUM stops applying any cost-based delay
- * that it started out with.
- *
- * Returns true when failsafe has been triggered.
- */
-static bool
-lazy_check_wraparound_failsafe(LVRelState *vacrel)
-{
-	Assert(TransactionIdIsNormal(vacrel->relfrozenxid));
-	Assert(MultiXactIdIsValid(vacrel->relminmxid));
-
-	/* Don't warn more than once per VACUUM */
-	if (vacrel->failsafe_active)
-		return true;
-
-	if (unlikely(vacuum_xid_failsafe_check(vacrel->relfrozenxid,
-										   vacrel->relminmxid)))
-	{
-		vacrel->failsafe_active = true;
-
-		/* Disable index vacuuming, index cleanup, and heap rel truncation */
-		vacrel->do_index_vacuuming = false;
-		vacrel->do_index_cleanup = false;
-		vacrel->do_rel_truncate = false;
-
-		ereport(WARNING,
-				(errmsg("bypassing nonessential maintenance of table \"%s.%s.%s\" as a failsafe after %d index scans",
-						get_database_name(MyDatabaseId),
-						vacrel->relnamespace,
-						vacrel->relname,
-						vacrel->num_index_scans),
-				 errdetail("The table's relfrozenxid or relminmxid is too far in the past."),
-				 errhint("Consider increasing configuration parameter \"maintenance_work_mem\" or \"autovacuum_work_mem\".\n"
-						 "You might also need to consider other ways for VACUUM to keep up with the allocation of transaction IDs.")));
-
-		/* Stop applying cost limits from this point on */
-		VacuumCostActive = false;
-		VacuumCostBalance = 0;
-
-		return true;
-	}
-
-	return false;
-}
-
 /*
  *	lazy_cleanup_all_indexes() -- cleanup all indexes of relation.
  */
@@ -3272,7 +3206,7 @@ heap_page_is_all_visible(LVRelState *vacrel, Buffer buf,
 		tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
 		tuple.t_len = ItemIdGetLength(itemid);
 		tuple.t_tableOid = RelationGetRelid(vacrel->rel);
-
+		HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(vacrel->rel));
 		switch (HeapTupleSatisfiesVacuum(&tuple, vacrel->OldestXmin, buf))
 		{
 			case HEAPTUPLE_LIVE:
@@ -3291,7 +3225,7 @@ heap_page_is_all_visible(LVRelState *vacrel, Buffer buf,
 					 * The inserter definitely committed. But is it old enough
 					 * that everyone sees it as committed?
 					 */
-					xmin = HeapTupleHeaderGetXmin(tuple.t_data);
+					xmin = HeapTupleGetXmin(&tuple);
 					if (!TransactionIdPrecedes(xmin, vacrel->OldestXmin))
 					{
 						all_visible = false;
@@ -3305,7 +3239,7 @@ heap_page_is_all_visible(LVRelState *vacrel, Buffer buf,
 
 					/* Check whether this tuple is already frozen or not */
 					if (all_visible && *all_frozen &&
-						heap_tuple_needs_eventual_freeze(tuple.t_data))
+						heap_tuple_needs_eventual_freeze(&tuple))
 						*all_frozen = false;
 				}
 				break;
diff --git a/src/backend/access/nbtree/nbtpage.c b/src/backend/access/nbtree/nbtpage.c
index 8b96708b3e..6c4b1f0f50 100644
--- a/src/backend/access/nbtree/nbtpage.c
+++ b/src/backend/access/nbtree/nbtpage.c
@@ -546,6 +546,7 @@ _bt_getroot(Relation rel, int access)
 			rootblkno = rootopaque->btpo_next;
 		}
 
+		/* Note: can't check btpo_level on deleted pages */
 		if (rootopaque->btpo_level != rootlevel)
 			elog(ERROR, "root page %u of index \"%s\" has level %u, expected %u",
 				 rootblkno, RelationGetRelationName(rel),
@@ -649,6 +650,7 @@ _bt_gettrueroot(Relation rel)
 		rootblkno = rootopaque->btpo_next;
 	}
 
+	/* Note: can't check btpo_level on deleted pages */
 	if (rootopaque->btpo_level != rootlevel)
 		elog(ERROR, "root page %u of index \"%s\" has level %u, expected %u",
 			 rootblkno, RelationGetRelationName(rel),
diff --git a/src/backend/access/nbtree/nbtsplitloc.c b/src/backend/access/nbtree/nbtsplitloc.c
index 241e26d338..c712ee645f 100644
--- a/src/backend/access/nbtree/nbtsplitloc.c
+++ b/src/backend/access/nbtree/nbtsplitloc.c
@@ -140,6 +140,7 @@ _bt_findsplitloc(Relation rel,
 				olddataitemstoleft,
 				perfectpenalty,
 				leaffillfactor;
+	int			maxTupleEnd PG_USED_FOR_ASSERTS_ONLY;
 	FindSplitData state;
 	FindSplitStrat strategy;
 	ItemId		itemid;
@@ -153,6 +154,7 @@ _bt_findsplitloc(Relation rel,
 
 	opaque = BTPageGetOpaque(origpage);
 	maxoff = PageGetMaxOffsetNumber(origpage);
+	maxTupleEnd = ItemIdGetTupleEnd(PageGetItemId(origpage, P_HIKEY));
 
 	/* Total free space available on a btree page, after fixed overhead */
 	leftspace = rightspace =
@@ -214,6 +216,18 @@ _bt_findsplitloc(Relation rel,
 		itemid = PageGetItemId(origpage, offnum);
 		itemsz = MAXALIGN(ItemIdGetLength(itemid)) + sizeof(ItemIdData);
 
+#ifdef USE_ASSERT_CHECKING
+
+		/*
+		 * Ending of rightmost tuple on a page can be shifted relative to left
+		 * boundary of BTPageOpaqueData due to conversion from EE96, which
+		 * used different BTPageOpaqueData layout. It is only checked in the
+		 * assert below.
+		 */
+		if (maxTupleEnd < ItemIdGetTupleEnd(itemid))
+			maxTupleEnd = ItemIdGetTupleEnd(itemid);
+#endif
+
 		/*
 		 * When item offset number is not newitemoff, neither side of the
 		 * split can be newitem.  Record a split after the previous data item
@@ -248,7 +262,7 @@ _bt_findsplitloc(Relation rel,
 	 * (Though only when it's possible that newitem will end up alone on new
 	 * right page.)
 	 */
-	Assert(olddataitemstoleft == olddataitemstotal);
+	Assert(olddataitemstoleft + ((PageHeader) origpage)->pd_special - maxTupleEnd == olddataitemstotal);
 	if (newitemoff > maxoff)
 		_bt_recsplitloc(&state, newitemoff, false, olddataitemstotal, 0);
 
diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index ad489e33b3..2c33033441 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -15,6 +15,8 @@
 #include "postgres.h"
 
 #include "access/bufmask.h"
+#include "access/heapam_xlog.h"
+#include "access/htup_details.h"
 #include "access/nbtree.h"
 #include "access/nbtxlog.h"
 #include "access/transam.h"
diff --git a/src/backend/access/rmgrdesc/gistdesc.c b/src/backend/access/rmgrdesc/gistdesc.c
index ad855894be..818c8c27ee 100644
--- a/src/backend/access/rmgrdesc/gistdesc.c
+++ b/src/backend/access/rmgrdesc/gistdesc.c
@@ -29,7 +29,7 @@ out_gistxlogPageReuse(StringInfo buf, gistxlogPageReuse *xlrec)
 	appendStringInfo(buf, "rel %u/%u/%u; blk %u; latestRemovedXid %llu",
 					 xlrec->locator.spcOid, xlrec->locator.dbOid,
 					 xlrec->locator.relNumber, xlrec->block,
-					 (unsigned long long) U64FromFullTransactionId(xlrec->latestRemovedFullXid));
+					 (unsigned long long) XidFromFullTransactionId(xlrec->latestRemovedFullXid));
 }
 
 static void
@@ -51,7 +51,7 @@ static void
 out_gistxlogPageDelete(StringInfo buf, gistxlogPageDelete *xlrec)
 {
 	appendStringInfo(buf, "deleteXid %llu; downlink %u",
-					 (unsigned long long) U64FromFullTransactionId(xlrec->deleteXid),
+					 (unsigned long long) XidFromFullTransactionId(xlrec->deleteXid),
 					 xlrec->downlinkOffset);
 }
 
diff --git a/src/backend/access/rmgrdesc/heapdesc.c b/src/backend/access/rmgrdesc/heapdesc.c
index 503808cf0a..407987d373 100644
--- a/src/backend/access/rmgrdesc/heapdesc.c
+++ b/src/backend/access/rmgrdesc/heapdesc.c
@@ -182,6 +182,23 @@ heap2_desc(StringInfo buf, XLogReaderState *record)
 	}
 }
 
+void
+heap3_desc(StringInfo buf, XLogReaderState *record)
+{
+	char	   *rec = XLogRecGetData(record);
+	uint8		info = XLogRecGetInfo(record) & ~XLR_INFO_MASK;
+
+	info &= XLOG_HEAP_OPMASK;
+	if (info == XLOG_HEAP3_BASE_SHIFT)
+	{
+		xl_heap_base_shift *xlrec = (xl_heap_base_shift *) rec;
+
+		appendStringInfo(buf, "%s delta %lld ",
+						 xlrec->multi ? "MultiXactId" : "XactId",
+						 (long long) xlrec->delta);
+	}
+}
+
 const char *
 heap_identify(uint8 info)
 {
@@ -265,3 +282,18 @@ heap2_identify(uint8 info)
 
 	return id;
 }
+
+const char *
+heap3_identify(uint8 info)
+{
+	const char *id = NULL;
+
+	switch (info & ~XLR_INFO_MASK)
+	{
+		case XLOG_HEAP3_BASE_SHIFT:
+			id = "BASE_SHIFT";
+			break;
+	}
+
+	return id;
+}
diff --git a/src/backend/access/rmgrdesc/mxactdesc.c b/src/backend/access/rmgrdesc/mxactdesc.c
index 950f9269f7..b9c1826770 100644
--- a/src/backend/access/rmgrdesc/mxactdesc.c
+++ b/src/backend/access/rmgrdesc/mxactdesc.c
@@ -65,9 +65,9 @@ multixact_desc(StringInfo buf, XLogReaderState *record)
 		xl_multixact_create *xlrec = (xl_multixact_create *) rec;
 		int			i;
 
-		appendStringInfo(buf, "%llu offset %u nmembers %d: ",
+		appendStringInfo(buf, "%llu offset %llu nmembers %d: ",
 						 (unsigned long long) xlrec->mid,
-						 xlrec->moff, xlrec->nmembers);
+						 (unsigned long long) xlrec->moff, xlrec->nmembers);
 		for (i = 0; i < xlrec->nmembers; i++)
 			out_member(buf, &xlrec->members[i]);
 	}
@@ -75,10 +75,11 @@ multixact_desc(StringInfo buf, XLogReaderState *record)
 	{
 		xl_multixact_truncate *xlrec = (xl_multixact_truncate *) rec;
 
-		appendStringInfo(buf, "offsets [%llu, %llu), members [%u, %u)",
+		appendStringInfo(buf, "offsets [%llu, %llu), members [%llu, %llu)",
 						 (unsigned long long) xlrec->startTruncOff,
 						 (unsigned long long) xlrec->endTruncOff,
-						 xlrec->startTruncMemb, xlrec->endTruncMemb);
+						 (unsigned long long) xlrec->startTruncMemb,
+						 (unsigned long long) xlrec->endTruncMemb);
 	}
 }
 
diff --git a/src/backend/access/rmgrdesc/nbtdesc.c b/src/backend/access/rmgrdesc/nbtdesc.c
index bf25c941e4..c739b65942 100644
--- a/src/backend/access/rmgrdesc/nbtdesc.c
+++ b/src/backend/access/rmgrdesc/nbtdesc.c
@@ -83,7 +83,7 @@ btree_desc(StringInfo buf, XLogReaderState *record)
 
 				appendStringInfo(buf, "left %u; right %u; level %u; safexid %llu; ",
 								 xlrec->leftsib, xlrec->rightsib, xlrec->level,
-								 (unsigned long long) U64FromFullTransactionId(xlrec->safexid));
+								 (unsigned long long) XidFromFullTransactionId(xlrec->safexid));
 				appendStringInfo(buf, "leafleft %u; leafright %u; leaftopparent %u",
 								 xlrec->leafleftsib, xlrec->leafrightsib,
 								 xlrec->leaftopparent);
@@ -103,7 +103,7 @@ btree_desc(StringInfo buf, XLogReaderState *record)
 				appendStringInfo(buf, "rel %u/%u/%u; latestRemovedXid %llu",
 								 xlrec->locator.spcOid, xlrec->locator.dbOid,
 								 xlrec->locator.relNumber,
-								 (unsigned long long) U64FromFullTransactionId(xlrec->latestRemovedFullXid));
+								 (unsigned long long) XidFromFullTransactionId(xlrec->latestRemovedFullXid));
 				break;
 			}
 		case XLOG_BTREE_META_CLEANUP:
diff --git a/src/backend/access/rmgrdesc/xactdesc.c b/src/backend/access/rmgrdesc/xactdesc.c
index b930943bb0..f97996d8e7 100644
--- a/src/backend/access/rmgrdesc/xactdesc.c
+++ b/src/backend/access/rmgrdesc/xactdesc.c
@@ -110,7 +110,8 @@ ParseCommitRecord(uint8 info, xl_xact_commit *xlrec, xl_xact_parsed_commit *pars
 	{
 		xl_xact_twophase *xl_twophase = (xl_xact_twophase *) data;
 
-		parsed->twophase_xid = xl_twophase->xid;
+		parsed->twophase_xid =
+			((uint64) xl_twophase->xid_hi << 32) | xl_twophase->xid_lo;
 
 		data += sizeof(xl_xact_twophase);
 
@@ -205,7 +206,8 @@ ParseAbortRecord(uint8 info, xl_xact_abort *xlrec, xl_xact_parsed_abort *parsed)
 	{
 		xl_xact_twophase *xl_twophase = (xl_xact_twophase *) data;
 
-		parsed->twophase_xid = xl_twophase->xid;
+		parsed->twophase_xid =
+			((uint64) xl_twophase->xid_hi << 32) | xl_twophase->xid_lo;
 
 		data += sizeof(xl_xact_twophase);
 
diff --git a/src/backend/access/rmgrdesc/xlogdesc.c b/src/backend/access/rmgrdesc/xlogdesc.c
index e7c357c8fd..927b2f8b3b 100644
--- a/src/backend/access/rmgrdesc/xlogdesc.c
+++ b/src/backend/access/rmgrdesc/xlogdesc.c
@@ -45,7 +45,7 @@ xlog_desc(StringInfo buf, XLogReaderState *record)
 		CheckPoint *checkpoint = (CheckPoint *) rec;
 
 		appendStringInfo(buf, "redo %X/%X; "
-						 "tli %u; prev tli %u; fpw %s; xid %llu; oid %u; multi %llu; offset %u; "
+						 "tli %u; prev tli %u; fpw %s; xid %llu; oid %u; multi %llu; offset %llu; "
 						 "oldest xid %llu in DB %u; oldest multi %llu in DB %u; "
 						 "oldest/newest commit timestamp xid: %llu/%llu; "
 						 "oldest running xid %llu; %s",
@@ -53,10 +53,10 @@ xlog_desc(StringInfo buf, XLogReaderState *record)
 						 checkpoint->ThisTimeLineID,
 						 checkpoint->PrevTimeLineID,
 						 checkpoint->fullPageWrites ? "true" : "false",
-						 (unsigned long long) U64FromFullTransactionId(checkpoint->nextXid),
+						 (unsigned long long) XidFromFullTransactionId(checkpoint->nextXid),
 						 checkpoint->nextOid,
 						 (unsigned long long) checkpoint->nextMulti,
-						 checkpoint->nextMultiOffset,
+						 (unsigned long long) checkpoint->nextMultiOffset,
 						 (unsigned long long) checkpoint->oldestXid,
 						 checkpoint->oldestXidDB,
 						 (unsigned long long) checkpoint->oldestMulti,
diff --git a/src/backend/access/transam/clog.c b/src/backend/access/transam/clog.c
index 46cb69ece0..f88bfd1021 100644
--- a/src/backend/access/transam/clog.c
+++ b/src/backend/access/transam/clog.c
@@ -294,7 +294,7 @@ TransactionIdSetPageStatus(TransactionId xid, int nsubxids,
 	 * sub-XIDs and all of the XIDs for which we're adjusting clog should be
 	 * on the same page.  Check those conditions, too.
 	 */
-	if (all_xact_same_page && xid == MyProc->xid &&
+	if (all_xact_same_page && xid == pg_atomic_read_u64(&MyProc->xid) &&
 		nsubxids <= THRESHOLD_SUBTRANS_CLOG_OPT &&
 		nsubxids == MyProc->subxidStatus.count &&
 		(nsubxids == 0 ||
@@ -713,7 +713,7 @@ void
 BootStrapCLOG(void)
 {
 	int			slotno;
-	int			pageno;
+	int64		pageno;
 
 	LWLockAcquire(XactSLRULock, LW_EXCLUSIVE);
 
@@ -727,7 +727,10 @@ BootStrapCLOG(void)
 	pageno = TransactionIdToPage(XidFromFullTransactionId(ShmemVariableCache->nextXid));
 	if (pageno != 0)
 	{
+		/* Create and zero the first page of the commit log */
 		slotno = ZeroCLOGPage(pageno, false);
+
+		/* Make sure it's written out */
 		SimpleLruWritePage(XactCtl, slotno);
 		Assert(!XactCtl->shared->page_dirty[slotno]);
 	}
@@ -921,24 +924,11 @@ TruncateCLOG(TransactionId oldestXact, Oid oldestxid_datoid)
 	SimpleLruTruncate(XactCtl, cutoffPage);
 }
 
-
 /*
  * Decide whether a CLOG page number is "older" for truncation purposes.
  *
- * We need to use comparison of TransactionIds here in order to do the right
- * thing with wraparound XID arithmetic.  However, TransactionIdPrecedes()
- * would get weird about permanent xact IDs.  So, offset both such that xid1,
- * xid2, and xid2 + CLOG_XACTS_PER_PAGE - 1 are all normal XIDs; this offset
- * is relevant to page 0 and to the page preceding page 0.
- *
- * The page containing oldestXact-2^31 is the important edge case.  The
- * portion of that page equaling or following oldestXact-2^31 is expendable,
- * but the portion preceding oldestXact-2^31 is not.  When oldestXact-2^31 is
- * the first XID of a page and segment, the entire page and segment is
- * expendable, and we could truncate the segment.  Recognizing that case would
- * require making oldestXact, not just the page containing oldestXact,
- * available to this callback.  The benefit would be rare and small, so we
- * don't optimize that edge case.
+ * With 64xid this function is just "<", but we left it as a function in order
+ * for its calls remain "vanilla" like.
  */
 static bool
 CLOGPagePrecedes(int64 page1, int64 page2)
diff --git a/src/backend/access/transam/commit_ts.c b/src/backend/access/transam/commit_ts.c
index f5713dd778..f08905d6a7 100644
--- a/src/backend/access/transam/commit_ts.c
+++ b/src/backend/access/transam/commit_ts.c
@@ -919,25 +919,6 @@ AdvanceOldestCommitTsXid(TransactionId oldestXact)
 /*
  * Decide whether a commitTS page number is "older" for truncation purposes.
  * Analogous to CLOGPagePrecedes().
- *
- * At default BLCKSZ, (1 << 31) % COMMIT_TS_XACTS_PER_PAGE == 128.  This
- * introduces differences compared to CLOG and the other SLRUs having (1 <<
- * 31) % per_page == 0.  This function never tests exactly
- * TransactionIdPrecedes(x-2^31, x).  When the system reaches xidStopLimit,
- * there are two possible counts of page boundaries between oldestXact and the
- * latest XID assigned, depending on whether oldestXact is within the first
- * 128 entries of its page.  Since this function doesn't know the location of
- * oldestXact within page2, it returns false for one page that actually is
- * expendable.  This is a wider (yet still negligible) version of the
- * truncation opportunity that CLOGPagePrecedes() cannot recognize.
- *
- * For the sake of a worked example, number entries with decimal values such
- * that page1==1 entries range from 1.0 to 1.999.  Let N+0.15 be the number of
- * pages that 2^31 entries will span (N is an integer).  If oldestXact=N+2.1,
- * then the final safe XID assignment leaves newestXact=1.95.  We keep page 2,
- * because entry=2.85 is the border that toggles whether entries precede the
- * last entry of the oldestXact page.  While page 2 is expendable at
- * oldestXact=N+2.1, it would be precious at oldestXact=N+2.9.
  */
 static bool
 CommitTsPagePrecedes(int64 page1, int64 page2)
diff --git a/src/backend/access/transam/multixact.c b/src/backend/access/transam/multixact.c
index 15ba6effc4..b4cdc875f8 100644
--- a/src/backend/access/transam/multixact.c
+++ b/src/backend/access/transam/multixact.c
@@ -112,15 +112,15 @@
 	((xid) / (MultiXactOffset) MULTIXACT_OFFSETS_PER_PAGE)
 #define MultiXactIdToOffsetEntry(xid) \
 	((xid) % (MultiXactOffset) MULTIXACT_OFFSETS_PER_PAGE)
-#define MultiXactIdToOffsetSegment(xid) (MultiXactIdToOffsetPage(xid) / SLRU_PAGES_PER_SEGMENT)
+#define MultiXactIdToOffsetSegment(xid) ((uint64)(MultiXactIdToOffsetPage(xid) / SLRU_PAGES_PER_SEGMENT))
 
 /*
  * The situation for members is a bit more complex: we store one byte of
  * additional flag bits for each TransactionId.  To do this without getting
- * into alignment issues, we store four bytes of flags, and then the
- * corresponding 4 Xids.  Each such 5-word (20-byte) set we call a "group", and
- * are stored as a whole in pages.  Thus, with 8kB BLCKSZ, we keep 409 groups
- * per page.  This wastes 12 bytes per page, but that's OK -- simplicity (and
+ * into alignment issues, we store eight bytes of flags, and then the
+ * corresponding 8 Xids.  Each such 9-word (72-byte) set we call a "group", and
+ * are stored as a whole in pages.  Thus, with 8kB BLCKSZ, we keep 113 groups
+ * per page.  This wastes 56 bytes per page, but that's OK -- simplicity (and
  * performance) trumps space efficiency here.
  *
  * Note that the "offset" macros work with byte offset, not array indexes, so
@@ -132,7 +132,7 @@
 #define MXACT_MEMBER_XACT_BITMASK	((1 << MXACT_MEMBER_BITS_PER_XACT) - 1)
 
 /* how many full bytes of flags are there in a group? */
-#define MULTIXACT_FLAGBYTES_PER_GROUP		4
+#define MULTIXACT_FLAGBYTES_PER_GROUP		8
 #define MULTIXACT_MEMBERS_PER_MEMBERGROUP	\
 	(MULTIXACT_FLAGBYTES_PER_GROUP * MXACT_MEMBER_FLAGS_PER_BYTE)
 /* size in bytes of a complete group */
@@ -142,22 +142,9 @@
 #define MULTIXACT_MEMBERS_PER_PAGE	\
 	(MULTIXACT_MEMBERGROUPS_PER_PAGE * MULTIXACT_MEMBERS_PER_MEMBERGROUP)
 
-/*
- * Because the number of items per page is not a divisor of the last item
- * number (member 0xFFFFFFFF), the last segment does not use the maximum number
- * of pages, and moreover the last used page therein does not use the same
- * number of items as previous pages.  (Another way to say it is that the
- * 0xFFFFFFFF member is somewhere in the middle of the last page, so the page
- * has some empty space after that item.)
- *
- * This constant is the number of members in the last page of the last segment.
- */
-#define MAX_MEMBERS_IN_LAST_MEMBERS_PAGE \
-		((uint32) ((0xFFFFFFFF % MULTIXACT_MEMBERS_PER_PAGE) + 1))
-
 /* page in which a member is to be found */
 #define MXOffsetToMemberPage(xid) ((xid) / (TransactionId) MULTIXACT_MEMBERS_PER_PAGE)
-#define MXOffsetToMemberSegment(xid) (MXOffsetToMemberPage(xid) / SLRU_PAGES_PER_SEGMENT)
+#define MXOffsetToMemberSegment(xid) ((uint64)(MXOffsetToMemberPage(xid) / SLRU_PAGES_PER_SEGMENT))
 
 /* Location (byte offset within page) of flag word for a given member */
 #define MXOffsetToFlagsOffset(xid) \
@@ -216,22 +203,8 @@ typedef struct MultiXactStateData
 	MultiXactId oldestMultiXactId;
 	Oid			oldestMultiXactDB;
 
-	/*
-	 * Oldest multixact offset that is potentially referenced by a multixact
-	 * referenced by a relation.  We don't always know this value, so there's
-	 * a flag here to indicate whether or not we currently do.
-	 */
-	MultiXactOffset oldestOffset;
-	bool		oldestOffsetKnown;
-
 	/* support for anti-wraparound measures */
 	MultiXactId multiVacLimit;
-	MultiXactId multiWarnLimit;
-	MultiXactId multiStopLimit;
-	MultiXactId multiWrapLimit;
-
-	/* support for members anti-wraparound measures */
-	MultiXactOffset offsetStopLimit;	/* known if oldestOffsetKnown */
 
 	/*
 	 * Per-backend data starts here.  We have two arrays stored in the area
@@ -361,9 +334,6 @@ static bool MultiXactOffsetPrecedes(MultiXactOffset offset1,
 									MultiXactOffset offset2);
 static void ExtendMultiXactOffset(MultiXactId multi);
 static void ExtendMultiXactMember(MultiXactOffset offset, int nmembers);
-static bool MultiXactOffsetWouldWrap(MultiXactOffset boundary,
-									 MultiXactOffset start, uint32 distance);
-static bool SetOffsetVacuumLimit(bool is_startup);
 static bool find_multixact_start(MultiXactId multi, MultiXactOffset *result);
 static void WriteMZeroPageXlogRec(int64 pageno, uint8 info);
 static void WriteMTruncateXlogRec(Oid oldestMultiDB,
@@ -397,6 +367,9 @@ MultiXactIdCreate(TransactionId xid1, MultiXactStatus status1,
 	/* MultiXactIdSetOldestMember() must have been called already. */
 	Assert(MultiXactIdIsValid(OldestMemberMXactId[MyBackendId]));
 
+	/* memset members array because with 64-bit xids it has a padding hole */
+	MemSet(members, 0, sizeof(members));
+
 	/*
 	 * Note: unlike MultiXactIdExpand, we don't bother to check that both XIDs
 	 * are still running.  In typical usage, xid2 will be our own XID and the
@@ -512,7 +485,7 @@ MultiXactIdExpand(MultiXactId multi, TransactionId xid, MultiXactStatus status)
 	 * end of the loop.
 	 */
 	newMembers = (MultiXactMember *)
-		palloc(sizeof(MultiXactMember) * (nmembers + 1));
+		palloc0(sizeof(MultiXactMember) * (nmembers + 1));
 
 	for (i = 0, j = 0; i < nmembers; i++)
 	{
@@ -527,7 +500,6 @@ MultiXactIdExpand(MultiXactId multi, TransactionId xid, MultiXactStatus status)
 
 	newMembers[j].xid = xid;
 	newMembers[j++].status = status;
-
 	newMulti = MultiXactIdCreateFromMembers(j, newMembers);
 
 	pfree(members);
@@ -903,8 +875,8 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
 	for (i = 0; i < nmembers; i++, offset++)
 	{
 		TransactionId *memberptr;
-		uint32	   *flagsptr;
-		uint32		flagsval;
+		uint64	   *flagsptr;
+		uint64		flagsval;
 		int			bshift;
 		int			flagsoff;
 		int			memberoff;
@@ -927,12 +899,12 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
 
 		*memberptr = members[i].xid;
 
-		flagsptr = (uint32 *)
+		flagsptr = (uint64 *)
 			(MultiXactMemberCtl->shared->page_buffer[slotno] + flagsoff);
 
 		flagsval = *flagsptr;
-		flagsval &= ~(((1 << MXACT_MEMBER_BITS_PER_XACT) - 1) << bshift);
-		flagsval |= (members[i].status << bshift);
+		flagsval &= ~((uint64) ((1ULL << MXACT_MEMBER_BITS_PER_XACT) - 1) << bshift);
+		flagsval |= ((uint64) members[i].status << bshift);
 		*flagsptr = flagsval;
 
 		MultiXactMemberCtl->shared->page_dirty[slotno] = true;
@@ -985,8 +957,6 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 	 * If we're past multiVacLimit or the safe threshold for member storage
 	 * space, or we don't know what the safe threshold for member storage is,
 	 * start trying to force autovacuum cycles.
-	 * If we're past multiWarnLimit, start issuing warnings.
-	 * If we're past multiStopLimit, refuse to create new MultiXactIds.
 	 *
 	 * Note these are pretty much the same protections in GetNewTransactionId.
 	 *----------
@@ -1000,41 +970,9 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 		 * possibility of deadlock while doing get_database_name(). First,
 		 * copy all the shared values we'll need in this path.
 		 */
-		MultiXactId multiWarnLimit = MultiXactState->multiWarnLimit;
-		MultiXactId multiStopLimit = MultiXactState->multiStopLimit;
-		MultiXactId multiWrapLimit = MultiXactState->multiWrapLimit;
-		Oid			oldest_datoid = MultiXactState->oldestMultiXactDB;
 
 		LWLockRelease(MultiXactGenLock);
 
-		if (IsUnderPostmaster &&
-			!MultiXactIdPrecedes(result, multiStopLimit))
-		{
-			char	   *oldest_datname = get_database_name(oldest_datoid);
-
-			/*
-			 * Immediately kick autovacuum into action as we're already in
-			 * ERROR territory.
-			 */
-			SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
-
-			/* complain even if that DB has disappeared */
-			if (oldest_datname)
-				ereport(ERROR,
-						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-						 errmsg("database is not accepting commands that generate new MultiXactIds to avoid wraparound data loss in database \"%s\"",
-								oldest_datname),
-						 errhint("Execute a database-wide VACUUM in that database.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-			else
-				ereport(ERROR,
-						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-						 errmsg("database is not accepting commands that generate new MultiXactIds to avoid wraparound data loss in database with OID %u",
-								oldest_datoid),
-						 errhint("Execute a database-wide VACUUM in that database.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		}
-
 		/*
 		 * To avoid swamping the postmaster with signals, we issue the autovac
 		 * request only once per 64K multis generated.  This still gives
@@ -1043,31 +981,6 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 		if (IsUnderPostmaster && (result % 65536) == 0)
 			SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
 
-		if (!MultiXactIdPrecedes(result, multiWarnLimit))
-		{
-			char	   *oldest_datname = get_database_name(oldest_datoid);
-
-			/* complain even if that DB has disappeared */
-			if (oldest_datname)
-				ereport(WARNING,
-						(errmsg_plural("database \"%s\" must be vacuumed before %u more MultiXactId is used",
-									   "database \"%s\" must be vacuumed before %u more MultiXactIds are used",
-									   multiWrapLimit - result,
-									   oldest_datname,
-									   multiWrapLimit - result),
-						 errhint("Execute a database-wide VACUUM in that database.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-			else
-				ereport(WARNING,
-						(errmsg_plural("database with OID %u must be vacuumed before %u more MultiXactId is used",
-									   "database with OID %u must be vacuumed before %u more MultiXactIds are used",
-									   multiWrapLimit - result,
-									   oldest_datoid,
-									   multiWrapLimit - result),
-						 errhint("Execute a database-wide VACUUM in that database.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		}
-
 		/* Re-acquire lock and start over */
 		LWLockAcquire(MultiXactGenLock, LW_EXCLUSIVE);
 		result = MultiXactState->nextMXact;
@@ -1092,78 +1005,6 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 	else
 		*offset = nextOffset;
 
-	/*----------
-	 * Protect against overrun of the members space as well, with the
-	 * following rules:
-	 *
-	 * If we're past offsetStopLimit, refuse to generate more multis.
-	 * If we're close to offsetStopLimit, emit a warning.
-	 *
-	 * Arbitrarily, we start emitting warnings when we're 20 segments or less
-	 * from offsetStopLimit.
-	 *
-	 * Note we haven't updated the shared state yet, so if we fail at this
-	 * point, the multixact ID we grabbed can still be used by the next guy.
-	 *
-	 * Note that there is no point in forcing autovacuum runs here: the
-	 * multixact freeze settings would have to be reduced for that to have any
-	 * effect.
-	 *----------
-	 */
-#define OFFSET_WARN_SEGMENTS	20
-	if (MultiXactState->oldestOffsetKnown &&
-		MultiXactOffsetWouldWrap(MultiXactState->offsetStopLimit, nextOffset,
-								 nmembers))
-	{
-		/* see comment in the corresponding offsets wraparound case */
-		SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
-
-		ereport(ERROR,
-				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-				 errmsg("multixact \"members\" limit exceeded"),
-				 errdetail_plural("This command would create a multixact with %u members, but the remaining space is only enough for %u member.",
-								  "This command would create a multixact with %u members, but the remaining space is only enough for %u members.",
-								  MultiXactState->offsetStopLimit - nextOffset - 1,
-								  nmembers,
-								  MultiXactState->offsetStopLimit - nextOffset - 1),
-				 errhint("Execute a database-wide VACUUM in database with OID %u with reduced vacuum_multixact_freeze_min_age and vacuum_multixact_freeze_table_age settings.",
-						 MultiXactState->oldestMultiXactDB)));
-	}
-
-	/*
-	 * Check whether we should kick autovacuum into action, to prevent members
-	 * wraparound. NB we use a much larger window to trigger autovacuum than
-	 * just the warning limit. The warning is just a measure of last resort -
-	 * this is in line with GetNewTransactionId's behaviour.
-	 */
-	if (!MultiXactState->oldestOffsetKnown ||
-		(MultiXactState->nextOffset - MultiXactState->oldestOffset
-		 > MULTIXACT_MEMBER_SAFE_THRESHOLD))
-	{
-		/*
-		 * To avoid swamping the postmaster with signals, we issue the autovac
-		 * request only when crossing a segment boundary. With default
-		 * compilation settings that's roughly after 50k members.  This still
-		 * gives plenty of chances before we get into real trouble.
-		 */
-		if ((MXOffsetToMemberPage(nextOffset) / SLRU_PAGES_PER_SEGMENT) !=
-			(MXOffsetToMemberPage(nextOffset + nmembers) / SLRU_PAGES_PER_SEGMENT))
-			SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
-	}
-
-	if (MultiXactState->oldestOffsetKnown &&
-		MultiXactOffsetWouldWrap(MultiXactState->offsetStopLimit,
-								 nextOffset,
-								 nmembers + MULTIXACT_MEMBERS_PER_PAGE * SLRU_PAGES_PER_SEGMENT * OFFSET_WARN_SEGMENTS))
-		ereport(WARNING,
-				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-				 errmsg_plural("database with OID %u must be vacuumed before %d more multixact member is used",
-							   "database with OID %u must be vacuumed before %d more multixact members are used",
-							   MultiXactState->offsetStopLimit - nextOffset + nmembers,
-							   MultiXactState->oldestMultiXactDB,
-							   MultiXactState->offsetStopLimit - nextOffset + nmembers),
-				 errhint("Execute a database-wide VACUUM in that database with reduced vacuum_multixact_freeze_min_age and vacuum_multixact_freeze_table_age settings.")));
-
 	ExtendMultiXactMember(nextOffset, nmembers);
 
 	/*
@@ -1192,8 +1033,8 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
 
 	LWLockRelease(MultiXactGenLock);
 
-	debug_elog4(DEBUG2, "GetNew: returning %llu offset %u",
-				(unsigned long long) result, *offset);
+	debug_elog4(DEBUG2, "GetNew: returning %llu offset %llu",
+				(unsigned long long) result, (unsigned long long) *offset);
 	return result;
 }
 
@@ -1303,14 +1144,14 @@ GetMultiXactIdMembers(MultiXactId multi, MultiXactMember **members,
 	if (MultiXactIdPrecedes(multi, oldestMXact))
 		ereport(ERROR,
 				(errcode(ERRCODE_INTERNAL_ERROR),
-				 errmsg("MultiXactId %u does no longer exist -- apparent wraparound",
-						multi)));
+				 errmsg("MultiXactId %llu does no longer exist -- apparent wraparound",
+						(unsigned long long) multi)));
 
 	if (!MultiXactIdPrecedes(multi, nextMXact))
 		ereport(ERROR,
 				(errcode(ERRCODE_INTERNAL_ERROR),
-				 errmsg("MultiXactId %u has not been created yet -- apparent wraparound",
-						multi)));
+				 errmsg("MultiXactId %llu has not been created yet -- apparent wraparound",
+						(unsigned long long) multi)));
 
 	/*
 	 * Find out the offset at which we need to start reading MultiXactMembers
@@ -1356,7 +1197,10 @@ retry:
 	offptr += entryno;
 	offset = *offptr;
 
-	Assert(offset != 0);
+	if (offset == 0)
+		ereport(ERROR,
+				(errmsg("found invalid zero offset in multixact %llu",
+						(unsigned long long) multi)));
 
 	/*
 	 * Use the same increment rule as GetNewMultiXactId(), that is, don't
@@ -1403,7 +1247,7 @@ retry:
 
 	LWLockRelease(MultiXactOffsetSLRULock);
 
-	ptr = (MultiXactMember *) palloc(length * sizeof(MultiXactMember));
+	ptr = (MultiXactMember *) palloc0(length * sizeof(MultiXactMember));
 
 	/* Now get the members themselves. */
 	LWLockAcquire(MultiXactMemberSLRULock, LW_EXCLUSIVE);
@@ -1413,7 +1257,7 @@ retry:
 	for (i = 0; i < length; i++, offset++)
 	{
 		TransactionId *xactptr;
-		uint32	   *flagsptr;
+		uint64	   *flagsptr;
 		int			flagsoff;
 		int			bshift;
 		int			memberoff;
@@ -1439,7 +1283,7 @@ retry:
 
 		flagsoff = MXOffsetToFlagsOffset(offset);
 		bshift = MXOffsetToFlagsBitShift(offset);
-		flagsptr = (uint32 *) (MultiXactMemberCtl->shared->page_buffer[slotno] + flagsoff);
+		flagsptr = (uint64 *) (MultiXactMemberCtl->shared->page_buffer[slotno] + flagsoff);
 
 		ptr[truelength].xid = *xactptr;
 		ptr[truelength].status = (*flagsptr >> bshift) & MXACT_MEMBER_XACT_BITMASK;
@@ -1904,7 +1748,7 @@ void
 BootStrapMultiXact(void)
 {
 	int			slotno;
-	int			pageno;
+	int64		pageno;
 
 	LWLockAcquire(MultiXactOffsetSLRULock, LW_EXCLUSIVE);
 
@@ -2225,8 +2069,9 @@ void
 MultiXactSetNextMXact(MultiXactId nextMulti,
 					  MultiXactOffset nextMultiOffset)
 {
-	debug_elog4(DEBUG2, "MultiXact: setting next multi to %llu offset %u",
-				(unsigned long long) nextMulti, nextMultiOffset);
+	debug_elog4(DEBUG2, "MultiXact: setting next multi to %llu offset %llu",
+				(unsigned long long) nextMulti,
+				(unsigned long long) nextMultiOffset);
 	LWLockAcquire(MultiXactGenLock, LW_EXCLUSIVE);
 	MultiXactState->nextMXact = nextMulti;
 	MultiXactState->nextOffset = nextMultiOffset;
@@ -2260,47 +2105,9 @@ SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid,
 					bool is_startup)
 {
 	MultiXactId multiVacLimit;
-	MultiXactId multiWarnLimit;
-	MultiXactId multiStopLimit;
-	MultiXactId multiWrapLimit;
-	MultiXactId curMulti;
-	bool		needs_offset_vacuum;
 
 	Assert(MultiXactIdIsValid(oldest_datminmxid));
 
-	/*
-	 * We pretend that a wrap will happen halfway through the multixact ID
-	 * space, but that's not really true, because multixacts wrap differently
-	 * from transaction IDs.  Note that, separately from any concern about
-	 * multixact IDs wrapping, we must ensure that multixact members do not
-	 * wrap.  Limits for that are set in SetOffsetVacuumLimit, not here.
-	 */
-	multiWrapLimit = oldest_datminmxid + (MaxMultiXactId >> 1);
-	if (multiWrapLimit < FirstMultiXactId)
-		multiWrapLimit += FirstMultiXactId;
-
-	/*
-	 * We'll refuse to continue assigning MultiXactIds once we get within 3M
-	 * multi of data loss.  See SetTransactionIdLimit.
-	 */
-	multiStopLimit = multiWrapLimit - 3000000;
-	if (multiStopLimit < FirstMultiXactId)
-		multiStopLimit -= FirstMultiXactId;
-
-	/*
-	 * We'll start complaining loudly when we get within 40M multis of data
-	 * loss.  This is kind of arbitrary, but if you let your gas gauge get
-	 * down to 2% of full, would you be looking for the next gas station?  We
-	 * need to be fairly liberal about this number because there are lots of
-	 * scenarios where most transactions are done by automatic clients that
-	 * won't pay attention to warnings.  (No, we're not gonna make this
-	 * configurable.  If you know enough to configure it, you know enough to
-	 * not get in this kind of trouble in the first place.)
-	 */
-	multiWarnLimit = multiWrapLimit - 40000000;
-	if (multiWarnLimit < FirstMultiXactId)
-		multiWarnLimit -= FirstMultiXactId;
-
 	/*
 	 * We'll start trying to force autovacuums when oldest_datminmxid gets to
 	 * be more than autovacuum_multixact_freeze_max_age mxids old.
@@ -2310,25 +2117,14 @@ SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid,
 	 * its value.  See SetTransactionIdLimit.
 	 */
 	multiVacLimit = oldest_datminmxid + autovacuum_multixact_freeze_max_age;
-	if (multiVacLimit < FirstMultiXactId)
-		multiVacLimit += FirstMultiXactId;
 
 	/* Grab lock for just long enough to set the new limit values */
 	LWLockAcquire(MultiXactGenLock, LW_EXCLUSIVE);
 	MultiXactState->oldestMultiXactId = oldest_datminmxid;
 	MultiXactState->oldestMultiXactDB = oldest_datoid;
 	MultiXactState->multiVacLimit = multiVacLimit;
-	MultiXactState->multiWarnLimit = multiWarnLimit;
-	MultiXactState->multiStopLimit = multiStopLimit;
-	MultiXactState->multiWrapLimit = multiWrapLimit;
-	curMulti = MultiXactState->nextMXact;
 	LWLockRelease(MultiXactGenLock);
 
-	/* Log the info */
-	ereport(DEBUG1,
-			(errmsg_internal("MultiXactId wrap limit is %u, limited by database with OID %u",
-							 multiWrapLimit, oldest_datoid)));
-
 	/*
 	 * Computing the actual limits is only possible once the data directory is
 	 * in a consistent state. There's no need to compute the limits while
@@ -2340,59 +2136,6 @@ SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid,
 		return;
 
 	Assert(!InRecovery);
-
-	/* Set limits for offset vacuum. */
-	needs_offset_vacuum = SetOffsetVacuumLimit(is_startup);
-
-	/*
-	 * If past the autovacuum force point, immediately signal an autovac
-	 * request.  The reason for this is that autovac only processes one
-	 * database per invocation.  Once it's finished cleaning up the oldest
-	 * database, it'll call here, and we'll signal the postmaster to start
-	 * another iteration immediately if there are still any old databases.
-	 */
-	if ((MultiXactIdPrecedes(multiVacLimit, curMulti) ||
-		 needs_offset_vacuum) && IsUnderPostmaster)
-		SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
-
-	/* Give an immediate warning if past the wrap warn point */
-	if (MultiXactIdPrecedes(multiWarnLimit, curMulti))
-	{
-		char	   *oldest_datname;
-
-		/*
-		 * We can be called when not inside a transaction, for example during
-		 * StartupXLOG().  In such a case we cannot do database access, so we
-		 * must just report the oldest DB's OID.
-		 *
-		 * Note: it's also possible that get_database_name fails and returns
-		 * NULL, for example because the database just got dropped.  We'll
-		 * still warn, even though the warning might now be unnecessary.
-		 */
-		if (IsTransactionState())
-			oldest_datname = get_database_name(oldest_datoid);
-		else
-			oldest_datname = NULL;
-
-		if (oldest_datname)
-			ereport(WARNING,
-					(errmsg_plural("database \"%s\" must be vacuumed before %u more MultiXactId is used",
-								   "database \"%s\" must be vacuumed before %u more MultiXactIds are used",
-								   multiWrapLimit - curMulti,
-								   oldest_datname,
-								   multiWrapLimit - curMulti),
-					 errhint("To avoid a database shutdown, execute a database-wide VACUUM in that database.\n"
-							 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		else
-			ereport(WARNING,
-					(errmsg_plural("database with OID %u must be vacuumed before %u more MultiXactId is used",
-								   "database with OID %u must be vacuumed before %u more MultiXactIds are used",
-								   multiWrapLimit - curMulti,
-								   oldest_datoid,
-								   multiWrapLimit - curMulti),
-					 errhint("To avoid a database shutdown, execute a database-wide VACUUM in that database.\n"
-							 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-	}
 }
 
 /*
@@ -2417,8 +2160,8 @@ MultiXactAdvanceNextMXact(MultiXactId minMulti,
 	}
 	if (MultiXactOffsetPrecedes(MultiXactState->nextOffset, minMultiOffset))
 	{
-		debug_elog3(DEBUG2, "MultiXact: setting next offset to %u",
-					minMultiOffset);
+		debug_elog3(DEBUG2, "MultiXact: setting next offset to %llu",
+					(unsigned long long) minMultiOffset);
 		MultiXactState->nextOffset = minMultiOffset;
 	}
 	LWLockRelease(MultiXactGenLock);
@@ -2490,7 +2233,7 @@ ExtendMultiXactMember(MultiXactOffset offset, int nmembers)
 	{
 		int			flagsoff;
 		int			flagsbit;
-		uint32		difference;
+		uint64		difference;
 
 		/*
 		 * Only zero when at first entry of a page.
@@ -2511,23 +2254,7 @@ ExtendMultiXactMember(MultiXactOffset offset, int nmembers)
 			LWLockRelease(MultiXactMemberSLRULock);
 		}
 
-		/*
-		 * Compute the number of items till end of current page.  Careful: if
-		 * addition of unsigned ints wraps around, we're at the last page of
-		 * the last segment; since that page holds a different number of items
-		 * than other pages, we need to do it differently.
-		 */
-		if (offset + MAX_MEMBERS_IN_LAST_MEMBERS_PAGE < offset)
-		{
-			/*
-			 * This is the last page of the last segment; we can compute the
-			 * number of items left to allocate in it without modulo
-			 * arithmetic.
-			 */
-			difference = MaxMultiXactOffset - offset + 1;
-		}
-		else
-			difference = MULTIXACT_MEMBERS_PER_PAGE - offset % MULTIXACT_MEMBERS_PER_PAGE;
+		difference = MULTIXACT_MEMBERS_PER_PAGE - offset % MULTIXACT_MEMBERS_PER_PAGE;
 
 		/*
 		 * Advance to next page, taking care to properly handle the wraparound
@@ -2591,184 +2318,6 @@ GetOldestMultiXactId(void)
 	return oldestMXact;
 }
 
-/*
- * Determine how aggressively we need to vacuum in order to prevent member
- * wraparound.
- *
- * To do so determine what's the oldest member offset and install the limit
- * info in MultiXactState, where it can be used to prevent overrun of old data
- * in the members SLRU area.
- *
- * The return value is true if emergency autovacuum is required and false
- * otherwise.
- */
-static bool
-SetOffsetVacuumLimit(bool is_startup)
-{
-	MultiXactId oldestMultiXactId;
-	MultiXactId nextMXact;
-	MultiXactOffset oldestOffset = 0;	/* placate compiler */
-	MultiXactOffset prevOldestOffset;
-	MultiXactOffset nextOffset;
-	bool		oldestOffsetKnown = false;
-	bool		prevOldestOffsetKnown;
-	MultiXactOffset offsetStopLimit = 0;
-	MultiXactOffset prevOffsetStopLimit;
-
-	/*
-	 * NB: Have to prevent concurrent truncation, we might otherwise try to
-	 * lookup an oldestMulti that's concurrently getting truncated away.
-	 */
-	LWLockAcquire(MultiXactTruncationLock, LW_SHARED);
-
-	/* Read relevant fields from shared memory. */
-	LWLockAcquire(MultiXactGenLock, LW_SHARED);
-	oldestMultiXactId = MultiXactState->oldestMultiXactId;
-	nextMXact = MultiXactState->nextMXact;
-	nextOffset = MultiXactState->nextOffset;
-	prevOldestOffsetKnown = MultiXactState->oldestOffsetKnown;
-	prevOldestOffset = MultiXactState->oldestOffset;
-	prevOffsetStopLimit = MultiXactState->offsetStopLimit;
-	Assert(MultiXactState->finishedStartup);
-	LWLockRelease(MultiXactGenLock);
-
-	/*
-	 * Determine the offset of the oldest multixact.  Normally, we can read
-	 * the offset from the multixact itself, but there's an important special
-	 * case: if there are no multixacts in existence at all, oldestMXact
-	 * obviously can't point to one.  It will instead point to the multixact
-	 * ID that will be assigned the next time one is needed.
-	 */
-	if (oldestMultiXactId == nextMXact)
-	{
-		/*
-		 * When the next multixact gets created, it will be stored at the next
-		 * offset.
-		 */
-		oldestOffset = nextOffset;
-		oldestOffsetKnown = true;
-	}
-	else
-	{
-		/*
-		 * Figure out where the oldest existing multixact's offsets are
-		 * stored. Due to bugs in early release of PostgreSQL 9.3.X and 9.4.X,
-		 * the supposedly-earliest multixact might not really exist.  We are
-		 * careful not to fail in that case.
-		 */
-		oldestOffsetKnown =
-			find_multixact_start(oldestMultiXactId, &oldestOffset);
-
-		if (oldestOffsetKnown)
-			ereport(DEBUG1,
-					(errmsg_internal("oldest MultiXactId member is at offset %llu",
-									 (unsigned long long) oldestOffset)));
-		else
-			ereport(LOG,
-					(errmsg("MultiXact member wraparound protections are disabled because oldest checkpointed MultiXact %llu does not exist on disk",
-							(unsigned long long) oldestMultiXactId)));
-	}
-
-	LWLockRelease(MultiXactTruncationLock);
-
-	/*
-	 * If we can, compute limits (and install them MultiXactState) to prevent
-	 * overrun of old data in the members SLRU area. We can only do so if the
-	 * oldest offset is known though.
-	 */
-	if (oldestOffsetKnown)
-	{
-		/* move back to start of the corresponding segment */
-		offsetStopLimit = oldestOffset - (oldestOffset %
-										  (MULTIXACT_MEMBERS_PER_PAGE * SLRU_PAGES_PER_SEGMENT));
-
-		/* always leave one segment before the wraparound point */
-		offsetStopLimit -= (MULTIXACT_MEMBERS_PER_PAGE * SLRU_PAGES_PER_SEGMENT);
-
-		if (!prevOldestOffsetKnown && !is_startup)
-			ereport(LOG,
-					(errmsg("MultiXact member wraparound protections are now enabled")));
-
-		ereport(DEBUG1,
-				(errmsg_internal("MultiXact member stop limit is now %llu based on MultiXact %llu",
-								 (unsigned long long) offsetStopLimit,
-								 (unsigned long long) oldestMultiXactId)));
-	}
-	else if (prevOldestOffsetKnown)
-	{
-		/*
-		 * If we failed to get the oldest offset this time, but we have a
-		 * value from a previous pass through this function, use the old
-		 * values rather than automatically forcing an emergency autovacuum
-		 * cycle again.
-		 */
-		oldestOffset = prevOldestOffset;
-		oldestOffsetKnown = true;
-		offsetStopLimit = prevOffsetStopLimit;
-	}
-
-	/* Install the computed values */
-	LWLockAcquire(MultiXactGenLock, LW_EXCLUSIVE);
-	MultiXactState->oldestOffset = oldestOffset;
-	MultiXactState->oldestOffsetKnown = oldestOffsetKnown;
-	MultiXactState->offsetStopLimit = offsetStopLimit;
-	LWLockRelease(MultiXactGenLock);
-
-	/*
-	 * Do we need an emergency autovacuum?	If we're not sure, assume yes.
-	 */
-	return !oldestOffsetKnown ||
-		(nextOffset - oldestOffset > MULTIXACT_MEMBER_SAFE_THRESHOLD);
-}
-
-/*
- * Return whether adding "distance" to "start" would move past "boundary".
- *
- * We use this to determine whether the addition is "wrapping around" the
- * boundary point, hence the name.  The reason we don't want to use the regular
- * 2^31-modulo arithmetic here is that we want to be able to use the whole of
- * the 2^32-1 space here, allowing for more multixacts than would fit
- * otherwise.
- */
-static bool
-MultiXactOffsetWouldWrap(MultiXactOffset boundary, MultiXactOffset start,
-						 uint32 distance)
-{
-	MultiXactOffset finish;
-
-	/*
-	 * Note that offset number 0 is not used (see GetMultiXactIdMembers), so
-	 * if the addition wraps around the UINT_MAX boundary, skip that value.
-	 */
-	finish = start + distance;
-	if (finish < start)
-		finish++;
-
-	/*-----------------------------------------------------------------------
-	 * When the boundary is numerically greater than the starting point, any
-	 * value numerically between the two is not wrapped:
-	 *
-	 *	<----S----B---->
-	 *	[---)			 = F wrapped past B (and UINT_MAX)
-	 *		 [---)		 = F not wrapped
-	 *			  [----] = F wrapped past B
-	 *
-	 * When the boundary is numerically less than the starting point (i.e. the
-	 * UINT_MAX wraparound occurs somewhere in between) then all values in
-	 * between are wrapped:
-	 *
-	 *	<----B----S---->
-	 *	[---)			 = F not wrapped past B (but wrapped past UINT_MAX)
-	 *		 [---)		 = F wrapped past B (and UINT_MAX)
-	 *			  [----] = F not wrapped
-	 *-----------------------------------------------------------------------
-	 */
-	if (start < boundary)
-		return finish >= boundary || finish < start;
-	else
-		return finish >= boundary && finish < start;
-}
-
 /*
  * Find the starting offset of the given MultiXactId.
  *
@@ -2812,97 +2361,6 @@ find_multixact_start(MultiXactId multi, MultiXactOffset *result)
 	return true;
 }
 
-/*
- * Determine how many multixacts, and how many multixact members, currently
- * exist.  Return false if unable to determine.
- */
-static bool
-ReadMultiXactCounts(uint32 *multixacts, MultiXactOffset *members)
-{
-	MultiXactOffset nextOffset;
-	MultiXactOffset oldestOffset;
-	MultiXactId oldestMultiXactId;
-	MultiXactId nextMultiXactId;
-	bool		oldestOffsetKnown;
-
-	LWLockAcquire(MultiXactGenLock, LW_SHARED);
-	nextOffset = MultiXactState->nextOffset;
-	oldestMultiXactId = MultiXactState->oldestMultiXactId;
-	nextMultiXactId = MultiXactState->nextMXact;
-	oldestOffset = MultiXactState->oldestOffset;
-	oldestOffsetKnown = MultiXactState->oldestOffsetKnown;
-	LWLockRelease(MultiXactGenLock);
-
-	if (!oldestOffsetKnown)
-		return false;
-
-	*members = nextOffset - oldestOffset;
-	*multixacts = nextMultiXactId - oldestMultiXactId;
-	return true;
-}
-
-/*
- * Multixact members can be removed once the multixacts that refer to them
- * are older than every datminmxid.  autovacuum_multixact_freeze_max_age and
- * vacuum_multixact_freeze_table_age work together to make sure we never have
- * too many multixacts; we hope that, at least under normal circumstances,
- * this will also be sufficient to keep us from using too many offsets.
- * However, if the average multixact has many members, we might exhaust the
- * members space while still using few enough members that these limits fail
- * to trigger full table scans for relminmxid advancement.  At that point,
- * we'd have no choice but to start failing multixact-creating operations
- * with an error.
- *
- * To prevent that, if more than a threshold portion of the members space is
- * used, we effectively reduce autovacuum_multixact_freeze_max_age and
- * to a value just less than the number of multixacts in use.  We hope that
- * this will quickly trigger autovacuuming on the table or tables with the
- * oldest relminmxid, thus allowing datminmxid values to advance and removing
- * some members.
- *
- * As the fraction of the member space currently in use grows, we become
- * more aggressive in clamping this value.  That not only causes autovacuum
- * to ramp up, but also makes any manual vacuums the user issues more
- * aggressive.  This happens because vacuum_set_xid_limits() clamps the
- * freeze table and the minimum freeze age based on the effective
- * autovacuum_multixact_freeze_max_age this function returns.  In the worst
- * case, we'll claim the freeze_max_age to zero, and every vacuum of any
- * table will try to freeze every multixact.
- *
- * It's possible that these thresholds should be user-tunable, but for now
- * we keep it simple.
- */
-int
-MultiXactMemberFreezeThreshold(void)
-{
-	MultiXactOffset members;
-	uint32		multixacts;
-	uint32		victim_multixacts;
-	double		fraction;
-
-	/* If we can't determine member space utilization, assume the worst. */
-	if (!ReadMultiXactCounts(&multixacts, &members))
-		return 0;
-
-	/* If member space utilization is low, no special action is required. */
-	if (members <= MULTIXACT_MEMBER_SAFE_THRESHOLD)
-		return autovacuum_multixact_freeze_max_age;
-
-	/*
-	 * Compute a target for relminmxid advancement.  The number of multixacts
-	 * we try to eliminate from the system is based on how far we are past
-	 * MULTIXACT_MEMBER_SAFE_THRESHOLD.
-	 */
-	fraction = (double) (members - MULTIXACT_MEMBER_SAFE_THRESHOLD) /
-		(MULTIXACT_MEMBER_DANGER_THRESHOLD - MULTIXACT_MEMBER_SAFE_THRESHOLD);
-	victim_multixacts = multixacts * fraction;
-
-	/* fraction could be > 1.0, but lowest possible freeze age is zero */
-	if (victim_multixacts > multixacts)
-		return 0;
-	return multixacts - victim_multixacts;
-}
-
 typedef struct mxtruncinfo
 {
 	int64		earliestExistingPage;
@@ -2929,35 +2387,12 @@ SlruScanDirCbFindEarliest(SlruCtl ctl, char *filename, int64 segpage, void *data
 
 /*
  * Delete members segments [oldest, newOldest)
- *
- * The members SLRU can, in contrast to the offsets one, be filled to almost
- * the full range at once. This means SimpleLruTruncate() can't trivially be
- * used - instead the to-be-deleted range is computed using the offsets
- * SLRU. C.f. TruncateMultiXact().
  */
 static void
 PerformMembersTruncation(MultiXactOffset oldestOffset, MultiXactOffset newOldestOffset)
 {
-	const int	maxsegment = MXOffsetToMemberSegment(MaxMultiXactOffset);
-	int			startsegment = MXOffsetToMemberSegment(oldestOffset);
-	int			endsegment = MXOffsetToMemberSegment(newOldestOffset);
-	int			segment = startsegment;
-
-	/*
-	 * Delete all the segments but the last one. The last segment can still
-	 * contain, possibly partially, valid data.
-	 */
-	while (segment != endsegment)
-	{
-		elog(DEBUG2, "truncating multixact members segment %x", segment);
-		SlruDeleteSegment(MultiXactMemberCtl, segment);
-
-		/* move to next segment, handling wraparound correctly */
-		if (segment == maxsegment)
-			segment = 0;
-		else
-			segment += 1;
-	}
+	SimpleLruTruncate(MultiXactMemberCtl,
+					  MXOffsetToMemberPage(newOldestOffset));
 }
 
 /*
@@ -3076,7 +2511,8 @@ TruncateMultiXact(MultiXactId newOldestMulti, Oid newOldestMultiDB)
 	{
 		ereport(LOG,
 				(errmsg("oldest MultiXact %llu not found, earliest MultiXact %llu, skipping truncation",
-						(unsigned long long) oldestMulti, (unsigned long long) earliest)));
+						(unsigned long long) oldestMulti,
+						(unsigned long long) earliest)));
 		LWLockRelease(MultiXactTruncationLock);
 		return;
 	}
@@ -3100,14 +2536,14 @@ TruncateMultiXact(MultiXactId newOldestMulti, Oid newOldestMultiDB)
 	}
 
 	elog(DEBUG1, "performing multixact truncation: "
-		 "offsets [%llu, %llu), offsets segments [%x, %x), "
-		 "members [%u, %u), members segments [%x, %x)",
+		 "offsets [%llu, %llu), offsets segments [%012llx, %012llx), "
+		 "members [%lld, %lld), members segments [%012llx, %012llx)",
 		 (unsigned long long) oldestMulti, (unsigned long long) newOldestMulti,
-		 MultiXactIdToOffsetSegment(oldestMulti),
-		 MultiXactIdToOffsetSegment(newOldestMulti),
-		 oldestOffset, newOldestOffset,
-		 MXOffsetToMemberSegment(oldestOffset),
-		 MXOffsetToMemberSegment(newOldestOffset));
+		 (unsigned long long) MultiXactIdToOffsetSegment(oldestMulti),
+		 (unsigned long long) MultiXactIdToOffsetSegment(newOldestMulti),
+		 (long long) oldestOffset, (long long) newOldestOffset,
+		 (unsigned long long) MXOffsetToMemberSegment(oldestOffset),
+		 (unsigned long long) MXOffsetToMemberSegment(newOldestOffset));
 
 	/*
 	 * Do truncation, and the WAL logging of the truncation, in a critical
@@ -3181,7 +2617,7 @@ MultiXactOffsetPagePrecedes(int64 page1, int64 page2)
 
 /*
  * Decide whether a MultiXactMember page number is "older" for truncation
- * purposes.  There is no "invalid offset number" so use the numbers verbatim.
+ * purposes. There is no "invalid offset number" so use the numbers verbatim.
  */
 static bool
 MultiXactMemberPagePrecedes(int64 page1, int64 page2)
@@ -3206,7 +2642,7 @@ MultiXactMemberPagePrecedes(int64 page1, int64 page2)
 bool
 MultiXactIdPrecedes(MultiXactId multi1, MultiXactId multi2)
 {
-	int32		diff = (int32) (multi1 - multi2);
+	int64		diff = (int64) (multi1 - multi2);
 
 	return (diff < 0);
 }
@@ -3220,7 +2656,7 @@ MultiXactIdPrecedes(MultiXactId multi1, MultiXactId multi2)
 bool
 MultiXactIdPrecedesOrEquals(MultiXactId multi1, MultiXactId multi2)
 {
-	int32		diff = (int32) (multi1 - multi2);
+	int64		diff = (int64) (multi1 - multi2);
 
 	return (diff <= 0);
 }
@@ -3232,7 +2668,7 @@ MultiXactIdPrecedesOrEquals(MultiXactId multi1, MultiXactId multi2)
 static bool
 MultiXactOffsetPrecedes(MultiXactOffset offset1, MultiXactOffset offset2)
 {
-	int32		diff = (int32) (offset1 - offset2);
+	int64		diff = (int64) (offset1 - offset2);
 
 	return (diff < 0);
 }
@@ -3356,15 +2792,16 @@ multixact_redo(XLogReaderState *record)
 			   SizeOfMultiXactTruncate);
 
 		elog(DEBUG1, "replaying multixact truncation: "
-			 "offsets [%llu, %llu), offsets segments [%x, %x), "
-			 "members [%u, %u), members segments [%x, %x)",
+			 "offsets [%llu, %llu), offsets segments [%012llx, %012llx), "
+			 "members [%llu, %llu), members segments [%012llx, %012llx)",
 			 (unsigned long long) xlrec.startTruncOff,
 			 (unsigned long long) xlrec.endTruncOff,
-			 MultiXactIdToOffsetSegment(xlrec.startTruncOff),
-			 MultiXactIdToOffsetSegment(xlrec.endTruncOff),
-			 xlrec.startTruncMemb, xlrec.endTruncMemb,
-			 MXOffsetToMemberSegment(xlrec.startTruncMemb),
-			 MXOffsetToMemberSegment(xlrec.endTruncMemb));
+			 (unsigned long long) MultiXactIdToOffsetSegment(xlrec.startTruncOff),
+			 (unsigned long long) MultiXactIdToOffsetSegment(xlrec.endTruncOff),
+			 (unsigned long long) xlrec.startTruncMemb,
+			 (unsigned long long) xlrec.endTruncMemb,
+			 (unsigned long long) MXOffsetToMemberSegment(xlrec.startTruncMemb),
+			 (unsigned long long) MXOffsetToMemberSegment(xlrec.endTruncMemb));
 
 		/* should not be required, but more than cheap enough */
 		LWLockAcquire(MultiXactTruncationLock, LW_EXCLUSIVE);
@@ -3408,7 +2845,8 @@ pg_get_multixact_members(PG_FUNCTION_ARGS)
 	if (mxid < FirstMultiXactId)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("invalid MultiXactId: %llu", (unsigned long long) mxid)));
+				 errmsg("invalid MultiXactId: %llu",
+						(unsigned long long) mxid)));
 
 	if (SRF_IS_FIRSTCALL())
 	{
diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c
index 9e765c6c28..c186e177ed 100644
--- a/src/backend/access/transam/slru.c
+++ b/src/backend/access/transam/slru.c
@@ -1428,7 +1428,7 @@ SlruPagePrecedesTestOffset(SlruCtl ctl, int per_page, uint32 offset)
 	 * must not assign.
 	 */
 	lhs = per_page + offset;	/* skip first page to avoid non-normal XIDs */
-	rhs = lhs + (1U << 31);
+	rhs = lhs + (1ULL << 63);
 	Assert(TransactionIdPrecedes(lhs, rhs));
 	Assert(TransactionIdPrecedes(rhs, lhs));
 	Assert(!TransactionIdPrecedes(lhs - 1, rhs));
@@ -1444,13 +1444,14 @@ SlruPagePrecedesTestOffset(SlruCtl ctl, int per_page, uint32 offset)
 	Assert(ctl->PagePrecedes(rhs / per_page, (lhs - 3 * per_page) / per_page));
 	Assert(ctl->PagePrecedes(rhs / per_page, (lhs - 2 * per_page) / per_page));
 	Assert(ctl->PagePrecedes(rhs / per_page, (lhs - 1 * per_page) / per_page)
-		   || (1U << 31) % per_page != 0);	/* See CommitTsPagePrecedes() */
+		   || (1ULL << 63) % per_page != 0);	/* See CommitTsPagePrecedes() */
 	Assert(ctl->PagePrecedes((lhs + 1 * per_page) / per_page, rhs / per_page)
-		   || (1U << 31) % per_page != 0);
+		   || (1ULL << 63) % per_page != 0);
 	Assert(ctl->PagePrecedes((lhs + 2 * per_page) / per_page, rhs / per_page));
 	Assert(ctl->PagePrecedes((lhs + 3 * per_page) / per_page, rhs / per_page));
 	Assert(!ctl->PagePrecedes(rhs / per_page, (lhs + per_page) / per_page));
 
+
 	/*
 	 * GetNewTransactionId() has assigned the last XID it can safely use, and
 	 * that XID is in the *LAST* page of the second segment.  We must not
@@ -1460,7 +1461,7 @@ SlruPagePrecedesTestOffset(SlruCtl ctl, int per_page, uint32 offset)
 	newestXact = newestPage * per_page + offset;
 	Assert(newestXact / per_page == newestPage);
 	oldestXact = newestXact + 1;
-	oldestXact -= 1U << 31;
+	oldestXact -= 1ULL << 63;
 	oldestPage = oldestXact / per_page;
 	Assert(!SlruMayDeleteSegment(ctl,
 								 (newestPage -
@@ -1476,7 +1477,7 @@ SlruPagePrecedesTestOffset(SlruCtl ctl, int per_page, uint32 offset)
 	newestXact = newestPage * per_page + offset;
 	Assert(newestXact / per_page == newestPage);
 	oldestXact = newestXact + 1;
-	oldestXact -= 1U << 31;
+	oldestXact -= 1ULL << 63;
 	oldestPage = oldestXact / per_page;
 	Assert(!SlruMayDeleteSegment(ctl,
 								 (newestPage -
@@ -1582,7 +1583,7 @@ SlruScanDirectory(SlruCtl ctl, SlruScanCallback callback, void *data)
 		if ((len == 12 || len == 13 || len == 14) &&
 			strspn(clde->d_name, "0123456789ABCDEF") == len)
 		{
-			segno = (int) strtol(clde->d_name, NULL, 16);
+			segno = (int) strtoi64(clde->d_name, NULL, 16);
 			segpage = segno * SLRU_PAGES_PER_SEGMENT;
 
 			elog(DEBUG2, "SlruScanDirectory invoking callback on %s/%s",
diff --git a/src/backend/access/transam/subtrans.c b/src/backend/access/transam/subtrans.c
index e2e20ed06c..2d124d9600 100644
--- a/src/backend/access/transam/subtrans.c
+++ b/src/backend/access/transam/subtrans.c
@@ -212,11 +212,14 @@ void
 BootStrapSUBTRANS(void)
 {
 	int			slotno;
+	int64		pageno;
+
+	pageno = TransactionIdToPage(XidFromFullTransactionId(ShmemVariableCache->nextXid));
 
 	LWLockAcquire(SubtransSLRULock, LW_EXCLUSIVE);
 
 	/* Create and zero the first page of the subtrans log */
-	slotno = ZeroSUBTRANSPage(0);
+	slotno = ZeroSUBTRANSPage(pageno);
 
 	/* Make sure it's written out */
 	SimpleLruWritePage(SubTransCtl, slotno);
@@ -269,9 +272,6 @@ StartupSUBTRANS(TransactionId oldestActiveXID)
 	{
 		(void) ZeroSUBTRANSPage(startPage);
 		startPage++;
-		/* must account for wraparound */
-		if (startPage > TransactionIdToPage(MaxTransactionId))
-			startPage = 0;
 	}
 	(void) ZeroSUBTRANSPage(startPage);
 
@@ -348,6 +348,7 @@ TruncateSUBTRANS(TransactionId oldestXact)
 	 * a page and oldestXact == next XID.  In that case, if we didn't subtract
 	 * one, we'd trigger SimpleLruTruncate's wraparound detection.
 	 */
+
 	TransactionIdRetreat(oldestXact);
 	cutoffPage = TransactionIdToPage(oldestXact);
 
diff --git a/src/backend/access/transam/transam.c b/src/backend/access/transam/transam.c
index 27410c4697..a2a41e58f2 100644
--- a/src/backend/access/transam/transam.c
+++ b/src/backend/access/transam/transam.c
@@ -274,14 +274,14 @@ TransactionIdPrecedes(TransactionId id1, TransactionId id2)
 {
 	/*
 	 * If either ID is a permanent XID then we can just do unsigned
-	 * comparison.  If both are normal, do a modulo-2^32 comparison.
+	 * comparison.  If both are normal, do a modulo-2^64 comparison.
 	 */
-	int32		diff;
+	int64		diff;
 
 	if (!TransactionIdIsNormal(id1) || !TransactionIdIsNormal(id2))
 		return (id1 < id2);
 
-	diff = (int32) (id1 - id2);
+	diff = (int64) (id1 - id2);
 	return (diff < 0);
 }
 
@@ -291,12 +291,12 @@ TransactionIdPrecedes(TransactionId id1, TransactionId id2)
 bool
 TransactionIdPrecedesOrEquals(TransactionId id1, TransactionId id2)
 {
-	int32		diff;
+	int64		diff;
 
 	if (!TransactionIdIsNormal(id1) || !TransactionIdIsNormal(id2))
 		return (id1 <= id2);
 
-	diff = (int32) (id1 - id2);
+	diff = (int64) (id1 - id2);
 	return (diff <= 0);
 }
 
@@ -306,12 +306,12 @@ TransactionIdPrecedesOrEquals(TransactionId id1, TransactionId id2)
 bool
 TransactionIdFollows(TransactionId id1, TransactionId id2)
 {
-	int32		diff;
+	int64		diff;
 
 	if (!TransactionIdIsNormal(id1) || !TransactionIdIsNormal(id2))
 		return (id1 > id2);
 
-	diff = (int32) (id1 - id2);
+	diff = (int64) (id1 - id2);
 	return (diff > 0);
 }
 
@@ -321,12 +321,12 @@ TransactionIdFollows(TransactionId id1, TransactionId id2)
 bool
 TransactionIdFollowsOrEquals(TransactionId id1, TransactionId id2)
 {
-	int32		diff;
+	int64		diff;
 
 	if (!TransactionIdIsNormal(id1) || !TransactionIdIsNormal(id2))
 		return (id1 >= id2);
 
-	diff = (int32) (id1 - id2);
+	diff = (int64) (id1 - id2);
 	return (diff >= 0);
 }
 
diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c
index 5deb27bb83..180ba530bb 100644
--- a/src/backend/access/transam/twophase.c
+++ b/src/backend/access/transam/twophase.c
@@ -476,8 +476,8 @@ MarkAsPreparingGuts(GlobalTransaction gxact, TransactionId xid, const char *gid,
 		proc->lxid = xid;
 		proc->backendId = InvalidBackendId;
 	}
-	proc->xid = xid;
-	Assert(proc->xmin == InvalidTransactionId);
+	pg_atomic_write_u64(&proc->xid, xid);
+	Assert(pg_atomic_read_u64(&proc->xmin) == InvalidTransactionId);
 	proc->delayChkptFlags = 0;
 	proc->statusFlags = 0;
 	proc->pid = 0;
@@ -794,7 +794,7 @@ pg_prepared_xact(PG_FUNCTION_ARGS)
 		MemSet(values, 0, sizeof(values));
 		MemSet(nulls, 0, sizeof(nulls));
 
-		values[0] = TransactionIdGetDatum(proc->xid);
+		values[0] = TransactionIdGetDatum(pg_atomic_read_u64(&proc->xid));
 		values[1] = CStringGetTextDatum(gxact->gid);
 		values[2] = TimestampTzGetDatum(gxact->prepared_at);
 		values[3] = ObjectIdGetDatum(gxact->owner);
@@ -945,7 +945,7 @@ TwoPhaseGetDummyProc(TransactionId xid, bool lock_held)
 /************************************************************************/
 
 #define TwoPhaseFilePath(path, xid) \
-	snprintf(path, MAXPGPATH, TWOPHASE_DIR "/%08X", xid)
+	snprintf(path, MAXPGPATH, TWOPHASE_DIR "/%016llX", (unsigned long long) xid)
 
 /*
  * 2PC state file format:
@@ -1884,13 +1884,13 @@ restoreTwoPhaseData(void)
 	cldir = AllocateDir(TWOPHASE_DIR);
 	while ((clde = ReadDir(cldir, TWOPHASE_DIR)) != NULL)
 	{
-		if (strlen(clde->d_name) == 8 &&
-			strspn(clde->d_name, "0123456789ABCDEF") == 8)
+		if (strlen(clde->d_name) == 16 &&
+			strspn(clde->d_name, "0123456789ABCDEF") == 16)
 		{
 			TransactionId xid;
 			char	   *buf;
 
-			xid = (TransactionId) strtoul(clde->d_name, NULL, 16);
+			xid = (TransactionId) strtou64(clde->d_name, NULL, 16);
 
 			buf = ProcessTwoPhaseBuffer(xid, InvalidXLogRecPtr,
 										true, false, false);
@@ -2222,7 +2222,6 @@ ProcessTwoPhaseBuffer(TransactionId xid,
 
 	if (fromdisk)
 	{
-		/* Read and validate file */
 		buf = ReadTwoPhaseFile(xid, false);
 	}
 	else
diff --git a/src/backend/access/transam/varsup.c b/src/backend/access/transam/varsup.c
index 849a7ce9d6..53c79d9a31 100644
--- a/src/backend/access/transam/varsup.c
+++ b/src/backend/access/transam/varsup.c
@@ -66,9 +66,9 @@ GetNewTransactionId(bool isSubXact)
 	if (IsBootstrapProcessingMode())
 	{
 		Assert(!isSubXact);
-		MyProc->xid = BootstrapTransactionId;
-		ProcGlobal->xids[MyProc->pgxactoff] = BootstrapTransactionId;
-		return FullTransactionIdFromEpochAndXid(0, BootstrapTransactionId);
+		pg_atomic_write_u64(&MyProc->xid, BootstrapTransactionId);
+		pg_atomic_write_u64(&ProcGlobal->xids[MyProc->pgxactoff], BootstrapTransactionId);
+		return FullTransactionIdFromXid(BootstrapTransactionId);
 	}
 
 	/* safety check, we should never get this far in a HS standby */
@@ -102,11 +102,6 @@ GetNewTransactionId(bool isSubXact)
 		 * possibility of deadlock while doing get_database_name(). First,
 		 * copy all the shared values we'll need in this path.
 		 */
-		TransactionId xidWarnLimit = ShmemVariableCache->xidWarnLimit;
-		TransactionId xidStopLimit = ShmemVariableCache->xidStopLimit;
-		TransactionId xidWrapLimit = ShmemVariableCache->xidWrapLimit;
-		Oid			oldest_datoid = ShmemVariableCache->oldestXidDB;
-
 		LWLockRelease(XidGenLock);
 
 		/*
@@ -117,48 +112,6 @@ GetNewTransactionId(bool isSubXact)
 		if (IsUnderPostmaster && (xid % 65536) == 0)
 			SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
 
-		if (IsUnderPostmaster &&
-			TransactionIdFollowsOrEquals(xid, xidStopLimit))
-		{
-			char	   *oldest_datname = get_database_name(oldest_datoid);
-
-			/* complain even if that DB has disappeared */
-			if (oldest_datname)
-				ereport(ERROR,
-						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-						 errmsg("database is not accepting commands to avoid wraparound data loss in database \"%s\"",
-								oldest_datname),
-						 errhint("Stop the postmaster and vacuum that database in single-user mode.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-			else
-				ereport(ERROR,
-						(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
-						 errmsg("database is not accepting commands to avoid wraparound data loss in database with OID %u",
-								oldest_datoid),
-						 errhint("Stop the postmaster and vacuum that database in single-user mode.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		}
-		else if (TransactionIdFollowsOrEquals(xid, xidWarnLimit))
-		{
-			char	   *oldest_datname = get_database_name(oldest_datoid);
-
-			/* complain even if that DB has disappeared */
-			if (oldest_datname)
-				ereport(WARNING,
-						(errmsg("database \"%s\" must be vacuumed within %u transactions",
-								oldest_datname,
-								xidWrapLimit - xid),
-						 errhint("To avoid a database shutdown, execute a database-wide VACUUM in that database.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-			else
-				ereport(WARNING,
-						(errmsg("database with OID %u must be vacuumed within %u transactions",
-								oldest_datoid,
-								xidWrapLimit - xid),
-						 errhint("To avoid a database shutdown, execute a database-wide VACUUM in that database.\n"
-								 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		}
-
 		/* Re-acquire lock and start over */
 		LWLockAcquire(XidGenLock, LW_EXCLUSIVE);
 		full_xid = ShmemVariableCache->nextXid;
@@ -228,8 +181,8 @@ GetNewTransactionId(bool isSubXact)
 		Assert(!MyProc->subxidStatus.overflowed);
 
 		/* LWLockRelease acts as barrier */
-		MyProc->xid = xid;
-		ProcGlobal->xids[MyProc->pgxactoff] = xid;
+		pg_atomic_write_u64(&MyProc->xid, xid);
+		pg_atomic_write_u64(&ProcGlobal->xids[MyProc->pgxactoff], xid);
 	}
 	else
 	{
@@ -270,7 +223,7 @@ ReadNextFullTransactionId(void)
 }
 
 /*
- * Advance nextXid to the value after a given xid.  The epoch is inferred.
+ * Advance nextXid to the value after a given xid.
  * This must only be called during recovery or from two-phase start-up code.
  */
 void
@@ -278,7 +231,6 @@ AdvanceNextFullTransactionIdPastXid(TransactionId xid)
 {
 	FullTransactionId newNextFullXid;
 	TransactionId next_xid;
-	uint32		epoch;
 
 	/*
 	 * It is safe to read nextXid without a lock, because this is only called
@@ -292,19 +244,9 @@ AdvanceNextFullTransactionIdPastXid(TransactionId xid)
 	if (!TransactionIdFollowsOrEquals(xid, next_xid))
 		return;
 
-	/*
-	 * Compute the FullTransactionId that comes after the given xid.  To do
-	 * this, we preserve the existing epoch, but detect when we've wrapped
-	 * into a new epoch.  This is necessary because WAL records and 2PC state
-	 * currently contain 32 bit xids.  The wrap logic is safe in those cases
-	 * because the span of active xids cannot exceed one epoch at any given
-	 * point in the WAL stream.
-	 */
+	/* Compute the FullTransactionId that comes after the given xid. */
 	TransactionIdAdvance(xid);
-	epoch = EpochFromFullTransactionId(ShmemVariableCache->nextXid);
-	if (unlikely(xid < next_xid))
-		++epoch;
-	newNextFullXid = FullTransactionIdFromEpochAndXid(epoch, xid);
+	newNextFullXid = FullTransactionIdFromXid(xid);
 
 	/*
 	 * We still need to take a lock to modify the value when there are
@@ -345,54 +287,10 @@ void
 SetTransactionIdLimit(TransactionId oldest_datfrozenxid, Oid oldest_datoid)
 {
 	TransactionId xidVacLimit;
-	TransactionId xidWarnLimit;
-	TransactionId xidStopLimit;
-	TransactionId xidWrapLimit;
 	TransactionId curXid;
 
 	Assert(TransactionIdIsNormal(oldest_datfrozenxid));
 
-	/*
-	 * The place where we actually get into deep trouble is halfway around
-	 * from the oldest potentially-existing XID.  (This calculation is
-	 * probably off by one or two counts, because the special XIDs reduce the
-	 * size of the loop a little bit.  But we throw in plenty of slop below,
-	 * so it doesn't matter.)
-	 */
-	xidWrapLimit = oldest_datfrozenxid + (MaxTransactionId >> 1);
-	if (xidWrapLimit < FirstNormalTransactionId)
-		xidWrapLimit += FirstNormalTransactionId;
-
-	/*
-	 * We'll refuse to continue assigning XIDs in interactive mode once we get
-	 * within 3M transactions of data loss.  This leaves lots of room for the
-	 * DBA to fool around fixing things in a standalone backend, while not
-	 * being significant compared to total XID space. (VACUUM requires an XID
-	 * if it truncates at wal_level!=minimal.  "VACUUM (ANALYZE)", which a DBA
-	 * might do by reflex, assigns an XID.  Hence, we had better be sure
-	 * there's lots of XIDs left...)  Also, at default BLCKSZ, this leaves two
-	 * completely-idle segments.  In the event of edge-case bugs involving
-	 * page or segment arithmetic, idle segments render the bugs unreachable
-	 * outside of single-user mode.
-	 */
-	xidStopLimit = xidWrapLimit - 3000000;
-	if (xidStopLimit < FirstNormalTransactionId)
-		xidStopLimit -= FirstNormalTransactionId;
-
-	/*
-	 * We'll start complaining loudly when we get within 40M transactions of
-	 * data loss.  This is kind of arbitrary, but if you let your gas gauge
-	 * get down to 2% of full, would you be looking for the next gas station?
-	 * We need to be fairly liberal about this number because there are lots
-	 * of scenarios where most transactions are done by automatic clients that
-	 * won't pay attention to warnings.  (No, we're not gonna make this
-	 * configurable.  If you know enough to configure it, you know enough to
-	 * not get in this kind of trouble in the first place.)
-	 */
-	xidWarnLimit = xidWrapLimit - 40000000;
-	if (xidWarnLimit < FirstNormalTransactionId)
-		xidWarnLimit -= FirstNormalTransactionId;
-
 	/*
 	 * We'll start trying to force autovacuums when oldest_datfrozenxid gets
 	 * to be more than autovacuum_freeze_max_age transactions old.
@@ -416,18 +314,10 @@ SetTransactionIdLimit(TransactionId oldest_datfrozenxid, Oid oldest_datoid)
 	LWLockAcquire(XidGenLock, LW_EXCLUSIVE);
 	ShmemVariableCache->oldestXid = oldest_datfrozenxid;
 	ShmemVariableCache->xidVacLimit = xidVacLimit;
-	ShmemVariableCache->xidWarnLimit = xidWarnLimit;
-	ShmemVariableCache->xidStopLimit = xidStopLimit;
-	ShmemVariableCache->xidWrapLimit = xidWrapLimit;
 	ShmemVariableCache->oldestXidDB = oldest_datoid;
 	curXid = XidFromFullTransactionId(ShmemVariableCache->nextXid);
 	LWLockRelease(XidGenLock);
 
-	/* Log the info */
-	ereport(DEBUG1,
-			(errmsg_internal("transaction ID wrap limit is %u, limited by database with OID %u",
-							 xidWrapLimit, oldest_datoid)));
-
 	/*
 	 * If past the autovacuum force point, immediately signal an autovac
 	 * request.  The reason for this is that autovac only processes one
@@ -438,41 +328,6 @@ SetTransactionIdLimit(TransactionId oldest_datfrozenxid, Oid oldest_datoid)
 	if (TransactionIdFollowsOrEquals(curXid, xidVacLimit) &&
 		IsUnderPostmaster && !InRecovery)
 		SendPostmasterSignal(PMSIGNAL_START_AUTOVAC_LAUNCHER);
-
-	/* Give an immediate warning if past the wrap warn point */
-	if (TransactionIdFollowsOrEquals(curXid, xidWarnLimit) && !InRecovery)
-	{
-		char	   *oldest_datname;
-
-		/*
-		 * We can be called when not inside a transaction, for example during
-		 * StartupXLOG().  In such a case we cannot do database access, so we
-		 * must just report the oldest DB's OID.
-		 *
-		 * Note: it's also possible that get_database_name fails and returns
-		 * NULL, for example because the database just got dropped.  We'll
-		 * still warn, even though the warning might now be unnecessary.
-		 */
-		if (IsTransactionState())
-			oldest_datname = get_database_name(oldest_datoid);
-		else
-			oldest_datname = NULL;
-
-		if (oldest_datname)
-			ereport(WARNING,
-					(errmsg("database \"%s\" must be vacuumed within %u transactions",
-							oldest_datname,
-							xidWrapLimit - curXid),
-					 errhint("To avoid a database shutdown, execute a database-wide VACUUM in that database.\n"
-							 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-		else
-			ereport(WARNING,
-					(errmsg("database with OID %u must be vacuumed within %u transactions",
-							oldest_datoid,
-							xidWrapLimit - curXid),
-					 errhint("To avoid a database shutdown, execute a database-wide VACUUM in that database.\n"
-							 "You might also need to commit or roll back old prepared transactions, or drop stale replication slots.")));
-	}
 }
 
 
diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c
index 843f3462f8..8d5f890d63 100644
--- a/src/backend/access/transam/xact.c
+++ b/src/backend/access/transam/xact.c
@@ -402,7 +402,6 @@ IsAbortedTransactionBlockState(void)
 	return false;
 }
 
-
 /*
  *	GetTopTransactionId
  *
@@ -5651,6 +5650,17 @@ XactLogCommitRecord(TimestampTz commit_time,
 		xl_subxacts.nsubxacts = nsubxacts;
 	}
 
+	if (TransactionIdIsValid(twophase_xid))
+	{
+		xl_xinfo.xinfo |= XACT_XINFO_HAS_TWOPHASE;
+		xl_twophase.xid_lo = (uint32) (twophase_xid & 0xFFFFFFFF);
+		xl_twophase.xid_hi = (uint32) (twophase_xid >> 32);
+		Assert(twophase_gid != NULL);
+
+		if (XLogLogicalInfoActive())
+			xl_xinfo.xinfo |= XACT_XINFO_HAS_GID;
+	}
+
 	if (nrels > 0)
 	{
 		xl_xinfo.xinfo |= XACT_XINFO_HAS_RELFILELOCATORS;
@@ -5670,16 +5680,6 @@ XactLogCommitRecord(TimestampTz commit_time,
 		xl_invals.nmsgs = nmsgs;
 	}
 
-	if (TransactionIdIsValid(twophase_xid))
-	{
-		xl_xinfo.xinfo |= XACT_XINFO_HAS_TWOPHASE;
-		xl_twophase.xid = twophase_xid;
-		Assert(twophase_gid != NULL);
-
-		if (XLogLogicalInfoActive())
-			xl_xinfo.xinfo |= XACT_XINFO_HAS_GID;
-	}
-
 	/* dump transaction origin information */
 	if (replorigin_session_origin != InvalidRepOriginId)
 	{
@@ -5800,6 +5800,17 @@ XactLogAbortRecord(TimestampTz abort_time,
 		xl_subxacts.nsubxacts = nsubxacts;
 	}
 
+	if (TransactionIdIsValid(twophase_xid))
+	{
+		xl_xinfo.xinfo |= XACT_XINFO_HAS_TWOPHASE;
+		xl_twophase.xid_lo = (uint32) (twophase_xid & 0xFFFFFFFF);
+		xl_twophase.xid_hi = (uint32) (twophase_xid >> 32);
+		Assert(twophase_gid != NULL);
+
+		if (XLogLogicalInfoActive())
+			xl_xinfo.xinfo |= XACT_XINFO_HAS_GID;
+	}
+
 	if (nrels > 0)
 	{
 		xl_xinfo.xinfo |= XACT_XINFO_HAS_RELFILELOCATORS;
@@ -5816,7 +5827,8 @@ XactLogAbortRecord(TimestampTz abort_time,
 	if (TransactionIdIsValid(twophase_xid))
 	{
 		xl_xinfo.xinfo |= XACT_XINFO_HAS_TWOPHASE;
-		xl_twophase.xid = twophase_xid;
+		xl_twophase.xid_lo = (uint32) (twophase_xid & 0xFFFFFFFF);
+		xl_twophase.xid_hi = (uint32) (twophase_xid >> 32);
 		Assert(twophase_gid != NULL);
 
 		if (XLogLogicalInfoActive())
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index ec0ba5fa13..aa2788eb52 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -4545,8 +4545,8 @@ BootStrapXLOG(void)
 	checkPoint.PrevTimeLineID = BootstrapTimeLineID;
 	checkPoint.fullPageWrites = fullPageWrites;
 	checkPoint.nextXid =
-		FullTransactionIdFromEpochAndXid(0, Max(FirstNormalTransactionId,
-												start_xid));
+		FullTransactionIdFromXid(Max(FirstNormalTransactionId,
+									 start_xid));
 	checkPoint.nextOid = FirstGenbkiObjectId;
 	checkPoint.nextMulti = Max(FirstMultiXactId, start_mxid);
 	checkPoint.nextMultiOffset = start_mxoff;
@@ -6634,7 +6634,7 @@ CreateCheckPoint(int flags)
 	UpdateControlFile();
 	LWLockRelease(ControlFileLock);
 
-	/* Update shared-memory copy of checkpoint XID/epoch */
+	/* Update shared-memory copy of checkpoint XID/base */
 	SpinLockAcquire(&XLogCtl->info_lck);
 	XLogCtl->ckptFullXid = checkPoint.nextXid;
 	SpinLockRelease(&XLogCtl->info_lck);
@@ -7660,7 +7660,7 @@ xlog_redo(XLogReaderState *record)
 		ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
 		LWLockRelease(ControlFileLock);
 
-		/* Update shared-memory copy of checkpoint XID/epoch */
+		/* Update shared-memory copy of checkpoint XID/base */
 		SpinLockAcquire(&XLogCtl->info_lck);
 		XLogCtl->ckptFullXid = checkPoint.nextXid;
 		SpinLockRelease(&XLogCtl->info_lck);
@@ -7721,7 +7721,7 @@ xlog_redo(XLogReaderState *record)
 		ControlFile->checkPointCopy.nextXid = checkPoint.nextXid;
 		LWLockRelease(ControlFileLock);
 
-		/* Update shared-memory copy of checkpoint XID/epoch */
+		/* Update shared-memory copy of checkpoint XID/base */
 		SpinLockAcquire(&XLogCtl->info_lck);
 		XLogCtl->ckptFullXid = checkPoint.nextXid;
 		SpinLockRelease(&XLogCtl->info_lck);
diff --git a/src/backend/access/transam/xloginsert.c b/src/backend/access/transam/xloginsert.c
index f3c29fa909..132cadf9bc 100644
--- a/src/backend/access/transam/xloginsert.c
+++ b/src/backend/access/transam/xloginsert.c
@@ -260,6 +260,11 @@ XLogRegisterBuffer(uint8 block_id, Buffer buffer, uint8 flags)
 	BufferGetTag(buffer, &regbuf->rlocator, &regbuf->forkno, &regbuf->block);
 	regbuf->page = BufferGetPage(buffer);
 	regbuf->flags = flags;
+	if (IsBufferConverted(buffer))
+	{
+		regbuf->flags |= REGBUF_CONVERTED;
+		MarkBufferConverted(buffer, false);
+	}
 	regbuf->rdata_tail = (XLogRecData *) &regbuf->rdata_head;
 	regbuf->rdata_len = 0;
 
@@ -575,6 +580,8 @@ XLogRecordAssemble(RmgrId rmid, uint8 info,
 			needs_backup = true;
 		else if (regbuf->flags & REGBUF_NO_IMAGE)
 			needs_backup = false;
+		else if (regbuf->flags & REGBUF_CONVERTED)
+			needs_backup = true;
 		else if (!doPageWrites)
 			needs_backup = false;
 		else
diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c
index f3dc4b7797..034f8def26 100644
--- a/src/backend/access/transam/xlogreader.c
+++ b/src/backend/access/transam/xlogreader.c
@@ -2102,37 +2102,3 @@ RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page)
 
 	return true;
 }
-
-#ifndef FRONTEND
-
-/*
- * Extract the FullTransactionId from a WAL record.
- */
-FullTransactionId
-XLogRecGetFullXid(XLogReaderState *record)
-{
-	TransactionId xid,
-				next_xid;
-	uint32		epoch;
-
-	/*
-	 * This function is only safe during replay, because it depends on the
-	 * replay state.  See AdvanceNextFullTransactionIdPastXid() for more.
-	 */
-	Assert(AmStartupProcess() || !IsUnderPostmaster);
-
-	xid = XLogRecGetXid(record);
-	next_xid = XidFromFullTransactionId(ShmemVariableCache->nextXid);
-	epoch = EpochFromFullTransactionId(ShmemVariableCache->nextXid);
-
-	/*
-	 * If xid is numerically greater than next_xid, it has to be from the last
-	 * epoch.
-	 */
-	if (unlikely(xid > next_xid))
-		--epoch;
-
-	return FullTransactionIdFromEpochAndXid(epoch, xid);
-}
-
-#endif
diff --git a/src/backend/access/transam/xlogrecovery.c b/src/backend/access/transam/xlogrecovery.c
index 5bf6618702..b40e31dfaa 100644
--- a/src/backend/access/transam/xlogrecovery.c
+++ b/src/backend/access/transam/xlogrecovery.c
@@ -812,7 +812,7 @@ InitWalRecovery(ControlFileData *ControlFile, bool *wasShutdown_ptr,
 							 wasShutdown ? "true" : "false")));
 	ereport(DEBUG1,
 			(errmsg_internal("next transaction ID: " UINT64_FORMAT "; next OID: %u",
-							 U64FromFullTransactionId(checkPoint.nextXid),
+							 XidFromFullTransactionId(checkPoint.nextXid),
 							 checkPoint.nextOid)));
 	ereport(DEBUG1,
 			(errmsg_internal("next MultiXactId: %llu; next MultiXactOffset: %llu",
diff --git a/src/backend/bootstrap/bootstrap.c b/src/backend/bootstrap/bootstrap.c
index ca8baae2a1..d93fbcef26 100644
--- a/src/backend/bootstrap/bootstrap.c
+++ b/src/backend/bootstrap/bootstrap.c
@@ -120,7 +120,7 @@ static const struct typinfo TypInfo[] = {
 	F_OIDIN, F_OIDOUT},
 	{"tid", TIDOID, 0, 6, false, TYPALIGN_SHORT, TYPSTORAGE_PLAIN, InvalidOid,
 	F_TIDIN, F_TIDOUT},
-	{"xid", XIDOID, 0, 4, true, TYPALIGN_INT, TYPSTORAGE_PLAIN, InvalidOid,
+	{"xid", XIDOID, 0, 8, FLOAT8PASSBYVAL, TYPALIGN_XID, TYPSTORAGE_PLAIN, InvalidOid,
 	F_XIDIN, F_XIDOUT},
 	{"cid", CIDOID, 0, 4, true, TYPALIGN_INT, TYPSTORAGE_PLAIN, InvalidOid,
 	F_CIDIN, F_CIDOUT},
@@ -252,15 +252,13 @@ BootstrapModeMain(int argc, char *argv[], bool check_only)
 				break;
 			case 'm':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_mxid = value;
+					start_mxid = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_mxid) /* overflow */
+						!StartMultiXactIdIsValid(start_mxid))
 					{
 						ereport(ERROR,
 								(errcode(ERRCODE_SYNTAX_ERROR),
@@ -270,15 +268,13 @@ BootstrapModeMain(int argc, char *argv[], bool check_only)
 				break;
 			case 'o':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_mxoff = value;
+					start_mxoff = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_mxoff) /* overflow */
+						!StartMultiXactOffsetIsValid(start_mxoff))
 					{
 						ereport(ERROR,
 								(errcode(ERRCODE_SYNTAX_ERROR),
@@ -303,15 +299,13 @@ BootstrapModeMain(int argc, char *argv[], bool check_only)
 				break;
 			case 'x':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_xid = value;
+					start_xid = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_xid) /* overflow */
+						!StartTransactionIdIsValid(start_xid))
 					{
 						ereport(ERROR,
 								(errcode(ERRCODE_SYNTAX_ERROR),
diff --git a/src/backend/catalog/heap.c b/src/backend/catalog/heap.c
index e770ea6eb8..07f7d3c169 100644
--- a/src/backend/catalog/heap.c
+++ b/src/backend/catalog/heap.c
@@ -159,8 +159,8 @@ static const FormData_pg_attribute a2 = {
 	.attnum = MinTransactionIdAttributeNumber,
 	.attcacheoff = -1,
 	.atttypmod = -1,
-	.attbyval = true,
-	.attalign = TYPALIGN_INT,
+	.attbyval = FLOAT8PASSBYVAL,
+	.attalign = TYPALIGN_XID,
 	.attstorage = TYPSTORAGE_PLAIN,
 	.attnotnull = true,
 	.attislocal = true,
@@ -187,8 +187,8 @@ static const FormData_pg_attribute a4 = {
 	.attnum = MaxTransactionIdAttributeNumber,
 	.attcacheoff = -1,
 	.atttypmod = -1,
-	.attbyval = true,
-	.attalign = TYPALIGN_INT,
+	.attbyval = FLOAT8PASSBYVAL,
+	.attalign = TYPALIGN_XID,
 	.attstorage = TYPSTORAGE_PLAIN,
 	.attnotnull = true,
 	.attislocal = true,
diff --git a/src/backend/catalog/pg_inherits.c b/src/backend/catalog/pg_inherits.c
index 92afbc2f25..3a1eda413f 100644
--- a/src/backend/catalog/pg_inherits.c
+++ b/src/backend/catalog/pg_inherits.c
@@ -146,7 +146,7 @@ find_inheritance_children_extended(Oid parentrelId, bool omit_detached,
 				TransactionId xmin;
 				Snapshot	snap;
 
-				xmin = HeapTupleHeaderGetXmin(inheritsTuple->t_data);
+				xmin = HeapTupleGetXmin(inheritsTuple);
 				snap = GetActiveSnapshot();
 
 				if (!XidInMVCCSnapshot(xmin, snap))
diff --git a/src/backend/commands/async.c b/src/backend/commands/async.c
index 056dca8e47..56295b9aa6 100644
--- a/src/backend/commands/async.c
+++ b/src/backend/commands/async.c
@@ -187,7 +187,7 @@ typedef struct AsyncQueueEntry
 } AsyncQueueEntry;
 
 /* Currently, no field of AsyncQueueEntry requires more than int alignment */
-#define QUEUEALIGN(len)		INTALIGN(len)
+#define QUEUEALIGN(len)		TYPEALIGN(8, len)
 
 #define AsyncQueueEntryEmptySize	(offsetof(AsyncQueueEntry, data) + 2)
 
diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 1901b434c5..a8c69d2e25 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -127,7 +127,8 @@ static void CreateDatabaseUsingWalLog(Oid src_dboid, Oid dboid, Oid src_tsid,
 static List *ScanSourceDatabasePgClass(Oid srctbid, Oid srcdbid, char *srcpath);
 static List *ScanSourceDatabasePgClassPage(Page page, Buffer buf, Oid tbid,
 										   Oid dbid, char *srcpath,
-										   List *rlocatorlist, Snapshot snapshot);
+										   List *rlocatorlist, Snapshot snapshot,
+										   bool is_toast);
 static CreateDBRelInfo *ScanSourceDatabasePgClassTuple(HeapTupleData *tuple,
 													   Oid tbid, Oid dbid,
 													   char *srcpath);
@@ -311,9 +312,10 @@ ScanSourceDatabasePgClass(Oid tbid, Oid dbid, char *srcpath)
 		}
 
 		/* Append relevant pg_class tuples for current page to rlocatorlist. */
+		/* No toast is expected in sys tables */
 		rlocatorlist = ScanSourceDatabasePgClassPage(page, buf, tbid, dbid,
 													 srcpath, rlocatorlist,
-													 snapshot);
+													 snapshot, false);
 
 		UnlockReleaseBuffer(buf);
 	}
@@ -331,7 +333,7 @@ ScanSourceDatabasePgClass(Oid tbid, Oid dbid, char *srcpath)
 static List *
 ScanSourceDatabasePgClassPage(Page page, Buffer buf, Oid tbid, Oid dbid,
 							  char *srcpath, List *rlocatorlist,
-							  Snapshot snapshot)
+							  Snapshot snapshot, bool is_toast)
 {
 	BlockNumber blkno = BufferGetBlockNumber(buf);
 	OffsetNumber offnum;
@@ -361,6 +363,7 @@ ScanSourceDatabasePgClassPage(Page page, Buffer buf, Oid tbid, Oid dbid,
 		tuple.t_data = (HeapTupleHeader) PageGetItem(page, itemid);
 		tuple.t_len = ItemIdGetLength(itemid);
 		tuple.t_tableOid = RelationRelationId;
+		HeapTupleCopyBaseFromPage(&tuple, page, is_toast);
 
 		/* Skip tuples that are not visible to this snapshot. */
 		if (HeapTupleSatisfiesVisibility(&tuple, snapshot, buf))
diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
index ff847579f3..2030be502b 100644
--- a/src/backend/commands/indexcmds.c
+++ b/src/backend/commands/indexcmds.c
@@ -1645,7 +1645,7 @@ DefineIndex(Oid relationId,
 		set_indexsafe_procflags();
 
 	/* We should now definitely not be advertising any xmin. */
-	Assert(MyProc->xmin == InvalidTransactionId);
+	Assert(pg_atomic_read_u64(&MyProc->xmin) == InvalidTransactionId);
 
 	/*
 	 * The index is now valid in the sense that it contains all currently
@@ -4317,8 +4317,8 @@ set_indexsafe_procflags(void)
 	 * This should only be called before installing xid or xmin in MyProc;
 	 * otherwise, concurrent processes could see an Xmin that moves backwards.
 	 */
-	Assert(MyProc->xid == InvalidTransactionId &&
-		   MyProc->xmin == InvalidTransactionId);
+	Assert(pg_atomic_read_u64(&MyProc->xid) == InvalidTransactionId &&
+		   pg_atomic_read_u64(&MyProc->xmin) == InvalidTransactionId);
 
 	LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
 	MyProc->statusFlags |= PROC_IN_SAFE_IC;
diff --git a/src/backend/commands/sequence.c b/src/backend/commands/sequence.c
index 48d9d43dac..149d5d8a18 100644
--- a/src/backend/commands/sequence.c
+++ b/src/backend/commands/sequence.c
@@ -48,6 +48,20 @@
 #include "utils/syscache.h"
 #include "utils/varlena.h"
 
+#define SeqTupleHeaderSetXmin(tup, xid) \
+( \
+	(tup)->t_choice.t_heap.t_xmin = (xid) \
+)
+
+#define SeqTupleHeaderSetXmax(tup, xid) \
+( \
+	(tup)->t_choice.t_heap.t_xmax = (xid) \
+)
+
+#define SeqTupleHeaderGetRawXmax(tup) \
+( \
+	(tup)->t_choice.t_heap.t_xmax \
+)
 
 /*
  * We don't want to log each fetching of a value from a sequence,
@@ -389,10 +403,10 @@ fill_seq_fork_with_data(Relation rel, HeapTuple tuple, ForkNumber forkNum)
 	 * because if the current transaction aborts, no other xact will ever
 	 * examine the sequence tuple anyway.
 	 */
-	HeapTupleHeaderSetXmin(tuple->t_data, FrozenTransactionId);
+	SeqTupleHeaderSetXmin(tuple->t_data, FrozenTransactionId);
 	HeapTupleHeaderSetXminFrozen(tuple->t_data);
 	HeapTupleHeaderSetCmin(tuple->t_data, FirstCommandId);
-	HeapTupleHeaderSetXmax(tuple->t_data, InvalidTransactionId);
+	SeqTupleHeaderSetXmax(tuple->t_data, InvalidTransactionId);
 	tuple->t_data->t_infomask |= HEAP_XMAX_INVALID;
 	ItemPointerSet(&tuple->t_data->t_ctid, 0, FirstOffsetNumber);
 
@@ -1224,9 +1238,9 @@ read_seq_tuple(Relation rel, Buffer *buf, HeapTuple seqdatatuple)
 	 * this again if the update gets lost.
 	 */
 	Assert(!(seqdatatuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI));
-	if (HeapTupleHeaderGetRawXmax(seqdatatuple->t_data) != InvalidTransactionId)
+	if (SeqTupleHeaderGetRawXmax(seqdatatuple->t_data) != InvalidTransactionId)
 	{
-		HeapTupleHeaderSetXmax(seqdatatuple->t_data, InvalidTransactionId);
+		SeqTupleHeaderSetXmax(seqdatatuple->t_data, InvalidTransactionId);
 		seqdatatuple->t_data->t_infomask &= ~HEAP_XMAX_COMMITTED;
 		seqdatatuple->t_data->t_infomask |= HEAP_XMAX_INVALID;
 		MarkBufferDirtyHint(*buf, true);
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 8df25f59d8..ff32b3b9f8 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -63,13 +63,12 @@
 /*
  * GUC parameters
  */
-int			vacuum_freeze_min_age;
-int			vacuum_freeze_table_age;
-int			vacuum_multixact_freeze_min_age;
-int			vacuum_multixact_freeze_table_age;
-int			vacuum_failsafe_age;
-int			vacuum_multixact_failsafe_age;
-
+int64		vacuum_freeze_min_age;
+int64		vacuum_freeze_table_age;
+int64		vacuum_multixact_freeze_min_age;
+int64		vacuum_multixact_freeze_table_age;
+int64		vacuum_failsafe_age;
+int64		vacuum_multixact_failsafe_age;
 
 /* A few variables that don't seem worth passing around as parameters */
 static MemoryContext vac_context = NULL;
@@ -957,23 +956,25 @@ get_all_vacuum_rels(int options)
  */
 bool
 vacuum_set_xid_limits(Relation rel,
-					  int freeze_min_age,
-					  int freeze_table_age,
-					  int multixact_freeze_min_age,
-					  int multixact_freeze_table_age,
+					  int64 freeze_min_age,
+					  int64 freeze_table_age,
+					  int64 multixact_freeze_min_age,
+					  int64 multixact_freeze_table_age,
 					  TransactionId *oldestXmin,
 					  MultiXactId *oldestMxact,
 					  TransactionId *freezeLimit,
 					  MultiXactId *multiXactCutoff)
 {
-	int			freezemin;
-	int			mxid_freezemin;
-	int			effective_multixact_freeze_max_age;
+	int64		freezemin;
+	int64		mxid_freezemin;
+	int64		effective_multixact_freeze_max_age;
 	TransactionId limit;
 	TransactionId safeLimit;
 	MultiXactId mxactLimit;
 	MultiXactId safeMxactLimit;
-	int			freezetable;
+	int64		freezetable;
+	TransactionId nextXid;
+	TransactionId nextMxactId;
 
 	/*
 	 * We can always ignore processes running lazy vacuum.  This is because we
@@ -1022,8 +1023,10 @@ vacuum_set_xid_limits(Relation rel,
 	/*
 	 * Compute the cutoff XID, being careful not to generate a "permanent" XID
 	 */
-	limit = *oldestXmin - freezemin;
-	if (!TransactionIdIsNormal(limit))
+	limit = *oldestXmin;
+	if (limit > FirstNormalTransactionId + freezemin)
+		limit -= freezemin;
+	else
 		limit = FirstNormalTransactionId;
 
 	/*
@@ -1031,8 +1034,10 @@ vacuum_set_xid_limits(Relation rel,
 	 * autovacuum_freeze_max_age / 2 XIDs old), complain and force a minimum
 	 * freeze age of zero.
 	 */
-	safeLimit = ReadNextTransactionId() - autovacuum_freeze_max_age;
-	if (!TransactionIdIsNormal(safeLimit))
+	nextXid = ReadNextTransactionId();
+	if (nextXid > FirstNormalTransactionId + autovacuum_freeze_max_age)
+		safeLimit = nextXid - autovacuum_freeze_max_age;
+	else
 		safeLimit = FirstNormalTransactionId;
 
 	if (TransactionIdPrecedes(limit, safeLimit))
@@ -1051,7 +1056,7 @@ vacuum_set_xid_limits(Relation rel,
 	 * normally autovacuum_multixact_freeze_max_age, but may be less if we are
 	 * short of multixact member space.
 	 */
-	effective_multixact_freeze_max_age = MultiXactMemberFreezeThreshold();
+	effective_multixact_freeze_max_age = autovacuum_multixact_freeze_max_age;
 
 	/*
 	 * Determine the minimum multixact freeze age to use: as specified by
@@ -1070,20 +1075,29 @@ vacuum_set_xid_limits(Relation rel,
 	*oldestMxact = GetOldestMultiXactId();
 
 	/* compute the cutoff multi, being careful to generate a valid value */
-	mxactLimit = *oldestMxact - mxid_freezemin;
-	if (mxactLimit < FirstMultiXactId)
+	if (*oldestMxact > FirstMultiXactId + mxid_freezemin)
+		mxactLimit = *oldestMxact - mxid_freezemin;
+	else
 		mxactLimit = FirstMultiXactId;
 
-	safeMxactLimit =
-		ReadNextMultiXactId() - effective_multixact_freeze_max_age;
-	if (safeMxactLimit < FirstMultiXactId)
+	nextMxactId = ReadNextMultiXactId();
+	if (nextMxactId > FirstMultiXactId + effective_multixact_freeze_max_age)
+		safeMxactLimit = nextMxactId - effective_multixact_freeze_max_age;
+	else
 		safeMxactLimit = FirstMultiXactId;
 
 	if (MultiXactIdPrecedes(mxactLimit, safeMxactLimit))
 	{
 		ereport(WARNING,
-				(errmsg("oldest multixact is far in the past"),
-				 errhint("Close open transactions with multixacts soon to avoid wraparound problems.")));
+				(errmsg("oldest multixact is far in the past: %lld %lld %llu %lld %llu %llu %lld ",
+						(long long) multixact_freeze_min_age,
+						(long long) vacuum_multixact_freeze_min_age,
+						(unsigned long long) mxactLimit,
+						(long long) mxid_freezemin,
+						(unsigned long long) *oldestMxact,
+						(unsigned long long) safeMxactLimit,
+						(long long) effective_multixact_freeze_max_age),
+				 errhint("Close open transactions with multixacts soon to enable SLRU truncation.")));
 		/* Use the safe limit, unless an older mxact is still running */
 		if (MultiXactIdPrecedes(*oldestMxact, safeMxactLimit))
 			mxactLimit = *oldestMxact;
@@ -1113,8 +1127,10 @@ vacuum_set_xid_limits(Relation rel,
 	 * Compute XID limit causing an aggressive vacuum, being careful not to
 	 * generate a "permanent" XID
 	 */
-	limit = ReadNextTransactionId() - freezetable;
-	if (!TransactionIdIsNormal(limit))
+	limit = ReadNextTransactionId();
+	if (limit > FirstNormalTransactionId + freezetable)
+		limit -= freezetable;
+	else
 		limit = FirstNormalTransactionId;
 	if (TransactionIdPrecedesOrEquals(rel->rd_rel->relfrozenxid,
 									  limit))
@@ -1139,8 +1155,10 @@ vacuum_set_xid_limits(Relation rel,
 	 * Compute MultiXact limit causing an aggressive vacuum, being careful to
 	 * generate a valid MultiXact value
 	 */
-	mxactLimit = ReadNextMultiXactId() - freezetable;
-	if (mxactLimit < FirstMultiXactId)
+	mxactLimit = ReadNextMultiXactId();
+	if (mxactLimit > FirstMultiXactId + freezetable)
+		mxactLimit -= freezetable;
+	else
 		mxactLimit = FirstMultiXactId;
 	if (MultiXactIdPrecedesOrEquals(rel->rd_rel->relminmxid,
 									mxactLimit))
@@ -1407,6 +1425,9 @@ vac_update_relstats(Relation relation,
 	futurexid = false;
 	if (frozenxid_updated)
 		*frozenxid_updated = false;
+
+	Assert(TransactionIdPrecedesOrEquals(frozenxid, ReadNextTransactionId()));
+
 	if (TransactionIdIsNormal(frozenxid) && oldfrozenxid != frozenxid)
 	{
 		bool		update = false;
@@ -1430,6 +1451,9 @@ vac_update_relstats(Relation relation,
 	futuremxid = false;
 	if (minmulti_updated)
 		*minmulti_updated = false;
+
+	Assert(MultiXactIdPrecedesOrEquals(minmulti, ReadNextMultiXactId()));
+
 	if (MultiXactIdIsValid(minmulti) && oldminmulti != minmulti)
 	{
 		bool		update = false;
@@ -1457,14 +1481,16 @@ vac_update_relstats(Relation relation,
 	if (futurexid)
 		ereport(WARNING,
 				(errcode(ERRCODE_DATA_CORRUPTED),
-				 errmsg_internal("overwrote invalid relfrozenxid value %u with new value %u for table \"%s\"",
-								 oldfrozenxid, frozenxid,
+				 errmsg_internal("overwrote invalid relfrozenxid value %llu with new value %llu for table \"%s\"",
+								 (unsigned long long) oldfrozenxid,
+								 (unsigned long long) frozenxid,
 								 RelationGetRelationName(relation))));
 	if (futuremxid)
 		ereport(WARNING,
 				(errcode(ERRCODE_DATA_CORRUPTED),
-				 errmsg_internal("overwrote invalid relminmxid value %u with new value %u for table \"%s\"",
-								 oldminmulti, minmulti,
+				 errmsg_internal("overwrote invalid relminmxid value %llu with new value %llu for table \"%s\"",
+								 (unsigned long long) oldminmulti,
+								 (unsigned long long) minmulti,
 								 RelationGetRelationName(relation))));
 }
 
diff --git a/src/backend/executor/execExprInterp.c b/src/backend/executor/execExprInterp.c
index 9fcb6be414..b7b4e8923e 100644
--- a/src/backend/executor/execExprInterp.c
+++ b/src/backend/executor/execExprInterp.c
@@ -3188,6 +3188,7 @@ ExecEvalFieldStoreDeForm(ExprState *state, ExprEvalStep *op, ExprContext *econte
 		tmptup.t_len = HeapTupleHeaderGetDatumLength(tuphdr);
 		ItemPointerSetInvalid(&(tmptup.t_self));
 		tmptup.t_tableOid = InvalidOid;
+		HeapTupleSetZeroBase(&tmptup);
 		tmptup.t_data = tuphdr;
 
 		heap_deform_tuple(&tmptup, tupDesc,
diff --git a/src/backend/executor/execUtils.c b/src/backend/executor/execUtils.c
index 9df1f81ea8..d8c92f4846 100644
--- a/src/backend/executor/execUtils.c
+++ b/src/backend/executor/execUtils.c
@@ -1070,6 +1070,7 @@ GetAttributeByName(HeapTupleHeader tuple, const char *attname, bool *isNull)
 	tmptup.t_len = HeapTupleHeaderGetDatumLength(tuple);
 	ItemPointerSetInvalid(&(tmptup.t_self));
 	tmptup.t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(&tmptup);
 	tmptup.t_data = tuple;
 
 	result = heap_getattr(&tmptup,
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
index a49c3da5b6..17bbc48762 100644
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -3677,6 +3677,7 @@ ExecModifyTable(PlanState *pstate)
 					HeapTupleHeaderGetDatumLength(oldtupdata.t_data);
 				ItemPointerSetInvalid(&(oldtupdata.t_self));
 				/* Historically, view triggers see invalid t_tableOid. */
+				HeapTupleCopyHeaderXids(&oldtupdata);
 				oldtupdata.t_tableOid =
 					(relkind == RELKIND_VIEW) ? InvalidOid :
 					RelationGetRelid(resultRelInfo->ri_RelationDesc);
diff --git a/src/backend/executor/spi.c b/src/backend/executor/spi.c
index 29bc26669b..fb03e6cc4b 100644
--- a/src/backend/executor/spi.c
+++ b/src/backend/executor/spi.c
@@ -1154,6 +1154,7 @@ SPI_modifytuple(Relation rel, HeapTuple tuple, int natts, int *attnum,
 		mtuple->t_data->t_ctid = tuple->t_data->t_ctid;
 		mtuple->t_self = tuple->t_self;
 		mtuple->t_tableOid = tuple->t_tableOid;
+		HeapTupleCopyBase(mtuple, tuple);
 	}
 	else
 	{
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 2c834e4d0d..04e5f9cab3 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -5982,6 +5982,7 @@ copyObjectImpl(const void *from)
 			 * perform a shallow copy via list_copy()
 			 */
 		case T_IntList:
+		case T_XidList:
 		case T_OidList:
 			retval = list_copy(from);
 			break;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 449352639f..2f2851fe9e 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -3506,6 +3506,13 @@ _equalList(const List *a, const List *b)
 					return false;
 			}
 			break;
+		case T_XidList:
+			forboth(item_a, a, item_b, b)
+			{
+				if (lfirst_xid(item_a) != lfirst_xid(item_b))
+					return false;
+			}
+			break;
 		case T_OidList:
 			forboth(item_a, a, item_b, b)
 			{
@@ -3824,6 +3831,7 @@ equal(const void *a, const void *b)
 
 		case T_List:
 		case T_IntList:
+		case T_XidList:
 		case T_OidList:
 			retval = _equalList(a, b);
 			break;
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 11e9cfe773..53389a2d54 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -2916,8 +2916,8 @@ _outIndexStmt(StringInfo str, const IndexStmt *node)
 	WRITE_STRING_FIELD(idxcomment);
 	WRITE_OID_FIELD(indexOid);
 	WRITE_OID_FIELD(oldNumber);
-	WRITE_UINT_FIELD(oldCreateSubid);
-	WRITE_UINT_FIELD(oldFirstRelfilelocatorSubid);
+	WRITE_UINT64_FIELD(oldCreateSubid);
+	WRITE_UINT64_FIELD(oldFirstRelfilelocatorSubid);
 	WRITE_BOOL_FIELD(unique);
 	WRITE_BOOL_FIELD(nulls_not_distinct);
 	WRITE_BOOL_FIELD(primary);
@@ -4020,7 +4020,7 @@ outNode(StringInfo str, const void *obj)
 
 	if (obj == NULL)
 		appendStringInfoString(str, "<>");
-	else if (IsA(obj, List) || IsA(obj, IntList) || IsA(obj, OidList))
+	else if (IsA(obj, List) || IsA(obj, IntList) || IsA(obj, XidList) || IsA(obj, OidList))
 		_outList(str, obj);
 	/* nodeRead does not want to see { } around these! */
 	else if (IsA(obj, Integer))
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index 5012bfe142..15ab82b384 100644
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -228,7 +228,7 @@ get_relation_info(PlannerInfo *root, Oid relationObjectId, bool inhparent,
 			 * src/backend/access/heap/README.HOT for discussion.
 			 */
 			if (index->indcheckxmin &&
-				!TransactionIdPrecedes(HeapTupleHeaderGetXmin(indexRelation->rd_indextuple->t_data),
+				!TransactionIdPrecedes(HeapTupleGetXmin(indexRelation->rd_indextuple),
 									   TransactionXmin))
 			{
 				root->glob->transientPlan = true;
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 2e146aac93..9b78e4e5fb 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -122,8 +122,8 @@ int			autovacuum_vac_ins_thresh;
 double		autovacuum_vac_ins_scale;
 int			autovacuum_anl_thresh;
 double		autovacuum_anl_scale;
-int			autovacuum_freeze_max_age;
-int			autovacuum_multixact_freeze_max_age;
+int64		autovacuum_freeze_max_age;
+int64		autovacuum_multixact_freeze_max_age;
 
 double		autovacuum_vac_cost_delay;
 int			autovacuum_vac_cost_limit;
@@ -146,10 +146,10 @@ static TransactionId recentXid;
 static MultiXactId recentMulti;
 
 /* Default freeze ages to use for autovacuum (varies by database) */
-static int	default_freeze_min_age;
-static int	default_freeze_table_age;
-static int	default_multixact_freeze_min_age;
-static int	default_multixact_freeze_table_age;
+static int64 default_freeze_min_age;
+static int64 default_freeze_table_age;
+static int64 default_multixact_freeze_min_age;
+static int64 default_multixact_freeze_table_age;
 
 /* Memory context for long-lived data */
 static MemoryContext AutovacMemCxt;
@@ -325,15 +325,15 @@ static void FreeWorkerInfo(int code, Datum arg);
 
 static autovac_table *table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 											TupleDesc pg_class_desc,
-											int effective_multixact_freeze_max_age);
+											int64 effective_multixact_freeze_max_age);
 static void recheck_relation_needs_vacanalyze(Oid relid, AutoVacOpts *avopts,
 											  Form_pg_class classForm,
-											  int effective_multixact_freeze_max_age,
+											  int64 effective_multixact_freeze_max_age,
 											  bool *dovacuum, bool *doanalyze, bool *wraparound);
 static void relation_needs_vacanalyze(Oid relid, AutoVacOpts *relopts,
 									  Form_pg_class classForm,
 									  PgStat_StatTabEntry *tabentry,
-									  int effective_multixact_freeze_max_age,
+									  int64 effective_multixact_freeze_max_age,
 									  bool *dovacuum, bool *doanalyze, bool *wraparound);
 
 static void autovacuum_do_vac_analyze(autovac_table *tab,
@@ -1149,6 +1149,7 @@ do_start_worker(void)
 	ListCell   *cell;
 	TransactionId xidForceLimit;
 	MultiXactId multiForceLimit;
+	int64		multiMembersThreshold;
 	bool		for_xid_wrap;
 	bool		for_multi_wrap;
 	avw_dbase  *avdb;
@@ -1185,17 +1186,18 @@ do_start_worker(void)
 	 * particular tables, but not loosened.)
 	 */
 	recentXid = ReadNextTransactionId();
-	xidForceLimit = recentXid - autovacuum_freeze_max_age;
-	/* ensure it's a "normal" XID, else TransactionIdPrecedes misbehaves */
-	/* this can cause the limit to go backwards by 3, but that's OK */
-	if (xidForceLimit < FirstNormalTransactionId)
-		xidForceLimit -= FirstNormalTransactionId;
+	if (recentXid > FirstNormalTransactionId + autovacuum_freeze_max_age)
+		xidForceLimit = recentXid - autovacuum_freeze_max_age;
+	else
+		xidForceLimit = FirstNormalTransactionId;
 
 	/* Also determine the oldest datminmxid we will consider. */
 	recentMulti = ReadNextMultiXactId();
-	multiForceLimit = recentMulti - MultiXactMemberFreezeThreshold();
-	if (multiForceLimit < FirstMultiXactId)
-		multiForceLimit -= FirstMultiXactId;
+	multiMembersThreshold = autovacuum_multixact_freeze_max_age;
+	if (recentMulti > FirstMultiXactId + multiMembersThreshold)
+		multiForceLimit = recentMulti - multiMembersThreshold;
+	else
+		multiForceLimit = FirstMultiXactId;
 
 	/*
 	 * Choose a database to connect to.  We pick the database that was least
@@ -1964,7 +1966,7 @@ do_autovacuum(void)
 	BufferAccessStrategy bstrategy;
 	ScanKeyData key;
 	TupleDesc	pg_class_desc;
-	int			effective_multixact_freeze_max_age;
+	int64		effective_multixact_freeze_max_age;
 	bool		did_vacuum = false;
 	bool		found_concurrent_worker = false;
 	int			i;
@@ -1987,7 +1989,7 @@ do_autovacuum(void)
 	 * normally autovacuum_multixact_freeze_max_age, but may be less if we are
 	 * short of multixact member space.
 	 */
-	effective_multixact_freeze_max_age = MultiXactMemberFreezeThreshold();
+	effective_multixact_freeze_max_age = autovacuum_multixact_freeze_max_age;
 
 	/*
 	 * Find the pg_database entry and select the default freeze ages. We use
@@ -2753,7 +2755,7 @@ extract_autovac_opts(HeapTuple tup, TupleDesc pg_class_desc)
 static autovac_table *
 table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 					  TupleDesc pg_class_desc,
-					  int effective_multixact_freeze_max_age)
+					  int64 effective_multixact_freeze_max_age)
 {
 	Form_pg_class classForm;
 	HeapTuple	classTup;
@@ -2792,10 +2794,10 @@ table_recheck_autovac(Oid relid, HTAB *table_toast_map,
 	/* OK, it needs something done */
 	if (doanalyze || dovacuum)
 	{
-		int			freeze_min_age;
-		int			freeze_table_age;
-		int			multixact_freeze_min_age;
-		int			multixact_freeze_table_age;
+		int64		freeze_min_age;
+		int64		freeze_table_age;
+		int64		multixact_freeze_min_age;
+		int64		multixact_freeze_table_age;
 		int			vac_cost_limit;
 		double		vac_cost_delay;
 		int			log_min_duration;
@@ -2900,7 +2902,7 @@ static void
 recheck_relation_needs_vacanalyze(Oid relid,
 								  AutoVacOpts *avopts,
 								  Form_pg_class classForm,
-								  int effective_multixact_freeze_max_age,
+								  int64 effective_multixact_freeze_max_age,
 								  bool *dovacuum,
 								  bool *doanalyze,
 								  bool *wraparound)
@@ -2962,7 +2964,7 @@ relation_needs_vacanalyze(Oid relid,
 						  AutoVacOpts *relopts,
 						  Form_pg_class classForm,
 						  PgStat_StatTabEntry *tabentry,
-						  int effective_multixact_freeze_max_age,
+						  int64 effective_multixact_freeze_max_age,
  /* output params below */
 						  bool *dovacuum,
 						  bool *doanalyze,
@@ -2991,8 +2993,8 @@ relation_needs_vacanalyze(Oid relid,
 				anltuples;
 
 	/* freeze parameters */
-	int			freeze_max_age;
-	int			multixact_freeze_max_age;
+	int64		freeze_max_age;
+	int64		multixact_freeze_max_age;
 	TransactionId xidForceLimit;
 	MultiXactId multiForceLimit;
 
@@ -3042,17 +3044,19 @@ relation_needs_vacanalyze(Oid relid,
 	av_enabled = (relopts ? relopts->enabled : true);
 
 	/* Force vacuum if table is at risk of wraparound */
-	xidForceLimit = recentXid - freeze_max_age;
-	if (xidForceLimit < FirstNormalTransactionId)
-		xidForceLimit -= FirstNormalTransactionId;
+	if (recentXid > FirstNormalTransactionId + freeze_max_age)
+		xidForceLimit = recentXid - freeze_max_age;
+	else
+		xidForceLimit = FirstNormalTransactionId;
 	force_vacuum = (TransactionIdIsNormal(classForm->relfrozenxid) &&
 					TransactionIdPrecedes(classForm->relfrozenxid,
 										  xidForceLimit));
 	if (!force_vacuum)
 	{
-		multiForceLimit = recentMulti - multixact_freeze_max_age;
-		if (multiForceLimit < FirstMultiXactId)
-			multiForceLimit -= FirstMultiXactId;
+		if (recentMulti > FirstMultiXactId + multixact_freeze_max_age)
+			multiForceLimit = recentMulti - multixact_freeze_max_age;
+		else
+			multiForceLimit = FirstMultiXactId;
 		force_vacuum = MultiXactIdIsValid(classForm->relminmxid) &&
 			MultiXactIdPrecedes(classForm->relminmxid, multiForceLimit);
 	}
diff --git a/src/backend/replication/logical/decode.c b/src/backend/replication/logical/decode.c
index c5c6a2ba68..136dd2cb19 100644
--- a/src/backend/replication/logical/decode.c
+++ b/src/backend/replication/logical/decode.c
@@ -846,8 +846,12 @@ DecodeInsert(LogicalDecodingContext *ctx, XLogRecordBuffer *buf)
 	xl_heap_insert *xlrec;
 	ReorderBufferChange *change;
 	RelFileLocator target_locator;
+	bool		isinit = (XLogRecGetInfo(r) & XLOG_HEAP_INIT_PAGE) != 0;
+	Pointer		rec_data = (Pointer) XLogRecGetData(r);
 
-	xlrec = (xl_heap_insert *) XLogRecGetData(r);
+	if (isinit)
+		rec_data += sizeof(TransactionId);
+	xlrec = (xl_heap_insert *) rec_data;
 
 	/*
 	 * Ignore insert records without new tuples (this does happen when
@@ -903,8 +907,12 @@ DecodeUpdate(LogicalDecodingContext *ctx, XLogRecordBuffer *buf)
 	ReorderBufferChange *change;
 	char	   *data;
 	RelFileLocator target_locator;
+	bool		isinit = (XLogRecGetInfo(r) & XLOG_HEAP_INIT_PAGE) != 0;
+	Pointer		rec_data = (Pointer) XLogRecGetData(r);
 
-	xlrec = (xl_heap_update *) XLogRecGetData(r);
+	if (isinit)
+		rec_data += sizeof(TransactionId);
+	xlrec = (xl_heap_update *) rec_data;
 
 	/* only interested in our database */
 	XLogRecGetBlockTag(r, 0, &target_locator, NULL, NULL);
@@ -1064,8 +1072,12 @@ DecodeMultiInsert(LogicalDecodingContext *ctx, XLogRecordBuffer *buf)
 	char	   *tupledata;
 	Size		tuplelen;
 	RelFileLocator rlocator;
+	bool		isinit = (XLogRecGetInfo(r) & XLOG_HEAP_INIT_PAGE) != 0;
+	Pointer		rec_data = (Pointer) XLogRecGetData(r);
 
-	xlrec = (xl_heap_multi_insert *) XLogRecGetData(r);
+	if (isinit)
+		rec_data += sizeof(TransactionId);
+	xlrec = (xl_heap_multi_insert *) rec_data;
 
 	/*
 	 * Ignore insert records without new tuples.  This happens when a
diff --git a/src/backend/replication/logical/proto.c b/src/backend/replication/logical/proto.c
index ff8513e2d2..c1c4adad9d 100644
--- a/src/backend/replication/logical/proto.c
+++ b/src/backend/replication/logical/proto.c
@@ -64,7 +64,7 @@ logicalrep_write_begin(StringInfo out, ReorderBufferTXN *txn)
 	/* fixed fields */
 	pq_sendint64(out, txn->final_lsn);
 	pq_sendint64(out, txn->xact_time.commit_time);
-	pq_sendint32(out, txn->xid);
+	pq_sendint64(out, txn->xid);
 }
 
 /*
@@ -78,7 +78,7 @@ logicalrep_read_begin(StringInfo in, LogicalRepBeginData *begin_data)
 	if (begin_data->final_lsn == InvalidXLogRecPtr)
 		elog(ERROR, "final_lsn not set in begin message");
 	begin_data->committime = pq_getmsgint64(in);
-	begin_data->xid = pq_getmsgint(in, 4);
+	begin_data->xid = pq_getmsgint64(in);
 }
 
 
@@ -132,7 +132,7 @@ logicalrep_write_begin_prepare(StringInfo out, ReorderBufferTXN *txn)
 	pq_sendint64(out, txn->final_lsn);
 	pq_sendint64(out, txn->end_lsn);
 	pq_sendint64(out, txn->xact_time.prepare_time);
-	pq_sendint32(out, txn->xid);
+	pq_sendint64(out, txn->xid);
 
 	/* send gid */
 	pq_sendstring(out, txn->gid);
@@ -152,7 +152,7 @@ logicalrep_read_begin_prepare(StringInfo in, LogicalRepPreparedTxnData *begin_da
 	if (begin_data->end_lsn == InvalidXLogRecPtr)
 		elog(ERROR, "end_lsn not set in begin prepare message");
 	begin_data->prepare_time = pq_getmsgint64(in);
-	begin_data->xid = pq_getmsgint(in, 4);
+	begin_data->xid = pq_getmsgint64(in);
 
 	/* read gid (copy it into a pre-allocated buffer) */
 	strlcpy(begin_data->gid, pq_getmsgstring(in), sizeof(begin_data->gid));
@@ -185,7 +185,7 @@ logicalrep_write_prepare_common(StringInfo out, LogicalRepMsgType type,
 	pq_sendint64(out, prepare_lsn);
 	pq_sendint64(out, txn->end_lsn);
 	pq_sendint64(out, txn->xact_time.prepare_time);
-	pq_sendint32(out, txn->xid);
+	pq_sendint64(out, txn->xid);
 
 	/* send gid */
 	pq_sendstring(out, txn->gid);
@@ -224,7 +224,7 @@ logicalrep_read_prepare_common(StringInfo in, char *msgtype,
 	if (prepare_data->end_lsn == InvalidXLogRecPtr)
 		elog(ERROR, "end_lsn is not set in %s message", msgtype);
 	prepare_data->prepare_time = pq_getmsgint64(in);
-	prepare_data->xid = pq_getmsgint(in, 4);
+	prepare_data->xid = pq_getmsgint64(in);
 	if (prepare_data->xid == InvalidTransactionId)
 		elog(ERROR, "invalid two-phase transaction ID in %s message", msgtype);
 
@@ -265,7 +265,7 @@ logicalrep_write_commit_prepared(StringInfo out, ReorderBufferTXN *txn,
 	pq_sendint64(out, commit_lsn);
 	pq_sendint64(out, txn->end_lsn);
 	pq_sendint64(out, txn->xact_time.commit_time);
-	pq_sendint32(out, txn->xid);
+	pq_sendint64(out, txn->xid);
 
 	/* send gid */
 	pq_sendstring(out, txn->gid);
@@ -291,7 +291,7 @@ logicalrep_read_commit_prepared(StringInfo in, LogicalRepCommitPreparedTxnData *
 	if (prepare_data->end_lsn == InvalidXLogRecPtr)
 		elog(ERROR, "end_lsn is not set in commit prepared message");
 	prepare_data->commit_time = pq_getmsgint64(in);
-	prepare_data->xid = pq_getmsgint(in, 4);
+	prepare_data->xid = pq_getmsgint64(in);
 
 	/* read gid (copy it into a pre-allocated buffer) */
 	strlcpy(prepare_data->gid, pq_getmsgstring(in), sizeof(prepare_data->gid));
@@ -323,7 +323,7 @@ logicalrep_write_rollback_prepared(StringInfo out, ReorderBufferTXN *txn,
 	pq_sendint64(out, txn->end_lsn);
 	pq_sendint64(out, prepare_time);
 	pq_sendint64(out, txn->xact_time.commit_time);
-	pq_sendint32(out, txn->xid);
+	pq_sendint64(out, txn->xid);
 
 	/* send gid */
 	pq_sendstring(out, txn->gid);
@@ -351,7 +351,7 @@ logicalrep_read_rollback_prepared(StringInfo in,
 		elog(ERROR, "rollback_end_lsn is not set in rollback prepared message");
 	rollback_data->prepare_time = pq_getmsgint64(in);
 	rollback_data->rollback_time = pq_getmsgint64(in);
-	rollback_data->xid = pq_getmsgint(in, 4);
+	rollback_data->xid = pq_getmsgint64(in);
 
 	/* read gid (copy it into a pre-allocated buffer) */
 	strlcpy(rollback_data->gid, pq_getmsgstring(in), sizeof(rollback_data->gid));
@@ -418,7 +418,7 @@ logicalrep_write_insert(StringInfo out, TransactionId xid, Relation rel,
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	/* use Oid as relation identifier */
 	pq_sendint32(out, RelationGetRelid(rel));
@@ -467,7 +467,7 @@ logicalrep_write_update(StringInfo out, TransactionId xid, Relation rel,
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	/* use Oid as relation identifier */
 	pq_sendint32(out, RelationGetRelid(rel));
@@ -541,7 +541,7 @@ logicalrep_write_delete(StringInfo out, TransactionId xid, Relation rel,
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	/* use Oid as relation identifier */
 	pq_sendint32(out, RelationGetRelid(rel));
@@ -595,7 +595,7 @@ logicalrep_write_truncate(StringInfo out,
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	pq_sendint32(out, nrelids);
 
@@ -653,7 +653,7 @@ logicalrep_write_message(StringInfo out, TransactionId xid, XLogRecPtr lsn,
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	pq_sendint8(out, flags);
 	pq_sendint64(out, lsn);
@@ -675,7 +675,7 @@ logicalrep_write_rel(StringInfo out, TransactionId xid, Relation rel,
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	/* use Oid as relation identifier */
 	pq_sendint32(out, RelationGetRelid(rel));
@@ -731,7 +731,7 @@ logicalrep_write_typ(StringInfo out, TransactionId xid, Oid typoid)
 
 	/* transaction ID (if not valid, we're not streaming) */
 	if (TransactionIdIsValid(xid))
-		pq_sendint32(out, xid);
+		pq_sendint64(out, xid);
 
 	tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(basetypoid));
 	if (!HeapTupleIsValid(tup))
@@ -1079,7 +1079,7 @@ logicalrep_write_stream_start(StringInfo out,
 	Assert(TransactionIdIsValid(xid));
 
 	/* transaction ID (we're starting to stream, so must be valid) */
-	pq_sendint32(out, xid);
+	pq_sendint64(out, xid);
 
 	/* 1 if this is the first streaming segment for this xid */
 	pq_sendbyte(out, first_segment ? 1 : 0);
@@ -1095,7 +1095,7 @@ logicalrep_read_stream_start(StringInfo in, bool *first_segment)
 
 	Assert(first_segment);
 
-	xid = pq_getmsgint(in, 4);
+	xid = pq_getmsgint64(in);
 	*first_segment = (pq_getmsgbyte(in) == 1);
 
 	return xid;
@@ -1124,7 +1124,7 @@ logicalrep_write_stream_commit(StringInfo out, ReorderBufferTXN *txn,
 	Assert(TransactionIdIsValid(txn->xid));
 
 	/* transaction ID */
-	pq_sendint32(out, txn->xid);
+	pq_sendint64(out, txn->xid);
 
 	/* send the flags field (unused for now) */
 	pq_sendbyte(out, flags);
@@ -1144,7 +1144,7 @@ logicalrep_read_stream_commit(StringInfo in, LogicalRepCommitData *commit_data)
 	TransactionId xid;
 	uint8		flags;
 
-	xid = pq_getmsgint(in, 4);
+	xid = pq_getmsgint64(in);
 
 	/* read flags (unused for now) */
 	flags = pq_getmsgbyte(in);
@@ -1173,8 +1173,8 @@ logicalrep_write_stream_abort(StringInfo out, TransactionId xid,
 	Assert(TransactionIdIsValid(xid) && TransactionIdIsValid(subxid));
 
 	/* transaction ID */
-	pq_sendint32(out, xid);
-	pq_sendint32(out, subxid);
+	pq_sendint64(out, xid);
+	pq_sendint64(out, subxid);
 }
 
 /*
@@ -1186,8 +1186,8 @@ logicalrep_read_stream_abort(StringInfo in, TransactionId *xid,
 {
 	Assert(xid && subxid);
 
-	*xid = pq_getmsgint(in, 4);
-	*subxid = pq_getmsgint(in, 4);
+	*xid = pq_getmsgint64(in);
+	*subxid = pq_getmsgint64(in);
 }
 
 /*
diff --git a/src/backend/replication/logical/reorderbuffer.c b/src/backend/replication/logical/reorderbuffer.c
index 491eba1d17..df57e0487f 100644
--- a/src/backend/replication/logical/reorderbuffer.c
+++ b/src/backend/replication/logical/reorderbuffer.c
@@ -5031,8 +5031,12 @@ UpdateLogicalMappings(HTAB *tuplecid_data, Oid relid, Snapshot snapshot)
 		TransactionId f_mapped_xid;
 		TransactionId f_create_xid;
 		XLogRecPtr	f_lsn;
-		uint32		f_hi,
-					f_lo;
+		uint32		f_lsn_hi,
+					f_lsn_lo,
+					f_mapped_xid_hi,
+					f_mapped_xid_lo,
+					f_create_xid_hi,
+					f_create_xid_lo;
 		RewriteMappingFile *f;
 
 		if (strcmp(mapping_de->d_name, ".") == 0 ||
@@ -5044,11 +5048,14 @@ UpdateLogicalMappings(HTAB *tuplecid_data, Oid relid, Snapshot snapshot)
 			continue;
 
 		if (sscanf(mapping_de->d_name, LOGICAL_REWRITE_FORMAT,
-				   &f_dboid, &f_relid, &f_hi, &f_lo,
-				   &f_mapped_xid, &f_create_xid) != 6)
+				   &f_dboid, &f_relid, &f_lsn_hi, &f_lsn_lo,
+				   &f_mapped_xid_hi, &f_mapped_xid_lo,
+				   &f_create_xid_hi, &f_create_xid_lo) != 8)
 			elog(ERROR, "could not parse filename \"%s\"", mapping_de->d_name);
 
-		f_lsn = ((uint64) f_hi) << 32 | f_lo;
+		f_lsn = ((uint64) f_lsn_hi) << 32 | f_lsn_lo;
+		f_mapped_xid = ((uint64) f_mapped_xid_hi) << 32 | f_mapped_xid_lo;
+		f_create_xid = ((uint64) f_create_xid_hi) << 32 | f_create_xid_lo;
 
 		/* mapping for another database */
 		if (f_dboid != dboid)
diff --git a/src/backend/replication/logical/snapbuild.c b/src/backend/replication/logical/snapbuild.c
index b901ea861f..ed2be103f2 100644
--- a/src/backend/replication/logical/snapbuild.c
+++ b/src/backend/replication/logical/snapbuild.c
@@ -544,7 +544,7 @@ SnapBuildInitialSnapshot(SnapBuild *builder)
 		elog(ERROR, "cannot build an initial slot snapshot, not all transactions are monitored anymore");
 
 	/* so we don't overwrite the existing value */
-	if (TransactionIdIsValid(MyProc->xmin))
+	if (TransactionIdIsValid(pg_atomic_read_u64(&MyProc->xmin)))
 		elog(ERROR, "cannot build an initial slot snapshot when MyProc->xmin already is valid");
 
 	snap = SnapBuildBuildSnapshot(builder);
@@ -566,7 +566,7 @@ SnapBuildInitialSnapshot(SnapBuild *builder)
 	}
 #endif
 
-	MyProc->xmin = snap->xmin;
+	pg_atomic_write_u64(&MyProc->xmin, snap->xmin);
 
 	/* allocate in transaction context */
 	newxip = (TransactionId *)
diff --git a/src/backend/replication/logical/worker.c b/src/backend/replication/logical/worker.c
index 247ed6c74a..b56fc40ecb 100644
--- a/src/backend/replication/logical/worker.c
+++ b/src/backend/replication/logical/worker.c
@@ -449,7 +449,7 @@ handle_streamed_transaction(LogicalRepMsgType action, StringInfo s)
 	 * We should have received XID of the subxact as the first part of the
 	 * message, so extract it.
 	 */
-	xid = pq_getmsgint(s, 4);
+	xid = pq_getmsgint64(s);
 
 	if (!TransactionIdIsValid(xid))
 		ereport(ERROR,
diff --git a/src/backend/replication/pgoutput/pgoutput.c b/src/backend/replication/pgoutput/pgoutput.c
index 2cbca4a087..4b5c62bd5e 100644
--- a/src/backend/replication/pgoutput/pgoutput.c
+++ b/src/backend/replication/pgoutput/pgoutput.c
@@ -565,7 +565,8 @@ pgoutput_commit_txn(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
 
 	if (!sent_begin_txn)
 	{
-		elog(DEBUG1, "skipped replication of an empty transaction with XID: %u", txn->xid);
+		elog(DEBUG1, "skipped replication of an empty transaction with XID: %llu",
+			 (unsigned long long) txn->xid);
 		return;
 	}
 
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index c5f4d6956e..02040b5a2e 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -1143,10 +1143,6 @@ static void
 XLogWalRcvSendHSFeedback(bool immed)
 {
 	TimestampTz now;
-	FullTransactionId nextFullXid;
-	TransactionId nextXid;
-	uint32		xmin_epoch,
-				catalog_xmin_epoch;
 	TransactionId xmin,
 				catalog_xmin;
 	static TimestampTz sendTime = 0;
@@ -1203,31 +1199,15 @@ XLogWalRcvSendHSFeedback(bool immed)
 		catalog_xmin = InvalidTransactionId;
 	}
 
-	/*
-	 * Get epoch and adjust if nextXid and oldestXmin are different sides of
-	 * the epoch boundary.
-	 */
-	nextFullXid = ReadNextFullTransactionId();
-	nextXid = XidFromFullTransactionId(nextFullXid);
-	xmin_epoch = EpochFromFullTransactionId(nextFullXid);
-	catalog_xmin_epoch = xmin_epoch;
-	if (nextXid < xmin)
-		xmin_epoch--;
-	if (nextXid < catalog_xmin)
-		catalog_xmin_epoch--;
-
-	elog(DEBUG2, "sending hot standby feedback xmin %llu epoch %u catalog_xmin %llu catalog_xmin_epoch %u",
-		 (unsigned long long) xmin, xmin_epoch,
-		 (unsigned long long) catalog_xmin, catalog_xmin_epoch);
+	elog(DEBUG2, "sending hot standby feedback xmin %llu catalog_xmin %llu",
+		 (unsigned long long) xmin, (unsigned long long) catalog_xmin);
 
 	/* Construct the message and send it. */
 	resetStringInfo(&reply_message);
 	pq_sendbyte(&reply_message, 'h');
 	pq_sendint64(&reply_message, GetCurrentTimestamp());
-	pq_sendint32(&reply_message, xmin);
-	pq_sendint32(&reply_message, xmin_epoch);
-	pq_sendint32(&reply_message, catalog_xmin);
-	pq_sendint32(&reply_message, catalog_xmin_epoch);
+	pq_sendint64(&reply_message, xmin);
+	pq_sendint64(&reply_message, catalog_xmin);
 	walrcv_send(wrconn, reply_message.data, reply_message.len);
 	if (TransactionIdIsValid(xmin) || TransactionIdIsValid(catalog_xmin))
 		primary_has_standby_xmin = true;
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index ec3f784f4a..2013e51d67 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -255,7 +255,6 @@ static void WalSndUpdateProgress(LogicalDecodingContext *ctx, XLogRecPtr lsn, Tr
 static XLogRecPtr WalSndWaitForWal(XLogRecPtr loc);
 static void LagTrackerWrite(XLogRecPtr lsn, TimestampTz local_flush_time);
 static TimeOffset LagTrackerRead(int head, XLogRecPtr lsn, TimestampTz now);
-static bool TransactionIdInRecentPast(TransactionId xid, uint32 epoch);
 
 static void WalSndSegmentOpen(XLogReaderState *state, XLogSegNo nextSegNo,
 							  TimeLineID *tli_p);
@@ -293,7 +292,7 @@ InitWalSender(void)
 	 */
 	if (MyDatabaseId == InvalidOid)
 	{
-		Assert(MyProc->xmin == InvalidTransactionId);
+		Assert(pg_atomic_read_u64(&MyProc->xmin) == InvalidTransactionId);
 		LWLockAcquire(ProcArrayLock, LW_EXCLUSIVE);
 		MyProc->statusFlags |= PROC_AFFECTS_ALL_HORIZONS;
 		ProcGlobal->statusFlags[MyProc->pgxactoff] = MyProc->statusFlags;
@@ -2171,7 +2170,7 @@ PhysicalReplicationSlotNewXmin(TransactionId feedbackXmin, TransactionId feedbac
 	ReplicationSlot *slot = MyReplicationSlot;
 
 	SpinLockAcquire(&slot->mutex);
-	MyProc->xmin = InvalidTransactionId;
+	pg_atomic_write_u64(&MyProc->xmin, InvalidTransactionId);
 
 	/*
 	 * For physical replication we don't need the interlock provided by xmin
@@ -2203,44 +2202,6 @@ PhysicalReplicationSlotNewXmin(TransactionId feedbackXmin, TransactionId feedbac
 	}
 }
 
-/*
- * Check that the provided xmin/epoch are sane, that is, not in the future
- * and not so far back as to be already wrapped around.
- *
- * Epoch of nextXid should be same as standby, or if the counter has
- * wrapped, then one greater than standby.
- *
- * This check doesn't care about whether clog exists for these xids
- * at all.
- */
-static bool
-TransactionIdInRecentPast(TransactionId xid, uint32 epoch)
-{
-	FullTransactionId nextFullXid;
-	TransactionId nextXid;
-	uint32		nextEpoch;
-
-	nextFullXid = ReadNextFullTransactionId();
-	nextXid = XidFromFullTransactionId(nextFullXid);
-	nextEpoch = EpochFromFullTransactionId(nextFullXid);
-
-	if (xid <= nextXid)
-	{
-		if (epoch != nextEpoch)
-			return false;
-	}
-	else
-	{
-		if (epoch + 1 != nextEpoch)
-			return false;
-	}
-
-	if (!TransactionIdPrecedesOrEquals(xid, nextXid))
-		return false;			/* epoch OK, but it's wrapped around */
-
-	return true;
-}
-
 /*
  * Hot Standby feedback
  */
@@ -2248,9 +2209,7 @@ static void
 ProcessStandbyHSFeedbackMessage(void)
 {
 	TransactionId feedbackXmin;
-	uint32		feedbackEpoch;
 	TransactionId feedbackCatalogXmin;
-	uint32		feedbackCatalogEpoch;
 	TimestampTz replyTime;
 
 	/*
@@ -2259,10 +2218,8 @@ ProcessStandbyHSFeedbackMessage(void)
 	 * of this message.
 	 */
 	replyTime = pq_getmsgint64(&reply_message);
-	feedbackXmin = pq_getmsgint(&reply_message, 4);
-	feedbackEpoch = pq_getmsgint(&reply_message, 4);
-	feedbackCatalogXmin = pq_getmsgint(&reply_message, 4);
-	feedbackCatalogEpoch = pq_getmsgint(&reply_message, 4);
+	feedbackXmin = pq_getmsgint64(&reply_message);
+	feedbackCatalogXmin = pq_getmsgint64(&reply_message);
 
 	if (message_level_is_interesting(DEBUG2))
 	{
@@ -2271,11 +2228,9 @@ ProcessStandbyHSFeedbackMessage(void)
 		/* Copy because timestamptz_to_str returns a static buffer */
 		replyTimeStr = pstrdup(timestamptz_to_str(replyTime));
 
-		elog(DEBUG2, "hot standby feedback xmin %llu epoch %u, catalog_xmin %llu epoch %u reply_time %s",
+		elog(DEBUG2, "hot standby feedback xmin %llu, catalog_xmin %llu reply_time %s",
 			 (unsigned long long) feedbackXmin,
-			 feedbackEpoch,
 			 (unsigned long long) feedbackCatalogXmin,
-			 feedbackCatalogEpoch,
 			 replyTimeStr);
 
 		pfree(replyTimeStr);
@@ -2300,24 +2255,12 @@ ProcessStandbyHSFeedbackMessage(void)
 	if (!TransactionIdIsNormal(feedbackXmin)
 		&& !TransactionIdIsNormal(feedbackCatalogXmin))
 	{
-		MyProc->xmin = InvalidTransactionId;
+		pg_atomic_write_u64(&MyProc->xmin, InvalidTransactionId);
 		if (MyReplicationSlot != NULL)
 			PhysicalReplicationSlotNewXmin(feedbackXmin, feedbackCatalogXmin);
 		return;
 	}
 
-	/*
-	 * Check that the provided xmin/epoch are sane, that is, not in the future
-	 * and not so far back as to be already wrapped around.  Ignore if not.
-	 */
-	if (TransactionIdIsNormal(feedbackXmin) &&
-		!TransactionIdInRecentPast(feedbackXmin, feedbackEpoch))
-		return;
-
-	if (TransactionIdIsNormal(feedbackCatalogXmin) &&
-		!TransactionIdInRecentPast(feedbackCatalogXmin, feedbackCatalogEpoch))
-		return;
-
 	/*
 	 * Set the WalSender's xmin equal to the standby's requested xmin, so that
 	 * the xmin will be taken into account by GetSnapshotData() /
@@ -2355,9 +2298,9 @@ ProcessStandbyHSFeedbackMessage(void)
 	{
 		if (TransactionIdIsNormal(feedbackCatalogXmin)
 			&& TransactionIdPrecedes(feedbackCatalogXmin, feedbackXmin))
-			MyProc->xmin = feedbackCatalogXmin;
+			pg_atomic_write_u64(&MyProc->xmin, feedbackCatalogXmin);
 		else
-			MyProc->xmin = feedbackXmin;
+			pg_atomic_write_u64(&MyProc->xmin, feedbackXmin);
 	}
 }
 
diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c
index 7c02fb279f..eadd52f406 100644
--- a/src/backend/statistics/extended_stats.c
+++ b/src/backend/statistics/extended_stats.c
@@ -2428,6 +2428,7 @@ statext_expressions_load(Oid stxoid, bool inh, int idx)
 	ItemPointerSetInvalid(&(tmptup.t_self));
 	tmptup.t_tableOid = InvalidOid;
 	tmptup.t_data = td;
+	HeapTupleCopyHeaderXids(&tmptup);
 
 	tup = heap_copytuple(&tmptup);
 
diff --git a/src/backend/storage/buffer/Makefile b/src/backend/storage/buffer/Makefile
index fd7c40dcb0..ffcc0fc290 100644
--- a/src/backend/storage/buffer/Makefile
+++ b/src/backend/storage/buffer/Makefile
@@ -17,6 +17,7 @@ OBJS = \
 	buf_table.o \
 	bufmgr.o \
 	freelist.o \
-	localbuf.o
+	localbuf.o \
+	heap_convert.o
 
 include $(top_srcdir)/src/backend/common.mk
diff --git a/src/backend/storage/buffer/bufmgr.c b/src/backend/storage/buffer/bufmgr.c
index e4de4b306c..6afcda25d4 100644
--- a/src/backend/storage/buffer/bufmgr.c
+++ b/src/backend/storage/buffer/bufmgr.c
@@ -459,7 +459,7 @@ ForgetPrivateRefCountEntry(PrivateRefCountEntry *ref)
 )
 
 
-static Buffer ReadBuffer_common(SMgrRelation reln, char relpersistence,
+static Buffer ReadBuffer_common(Relation rel, SMgrRelation reln, char relpersistence,
 								ForkNumber forkNum, BlockNumber blockNum,
 								ReadBufferMode mode, BufferAccessStrategy strategy,
 								bool *hit);
@@ -767,7 +767,8 @@ ReadBufferExtended(Relation reln, ForkNumber forkNum, BlockNumber blockNum,
 	 * miss.
 	 */
 	pgstat_count_buffer_read(reln);
-	buf = ReadBuffer_common(RelationGetSmgr(reln), reln->rd_rel->relpersistence,
+	buf = ReadBuffer_common(reln, RelationGetSmgr(reln),
+							reln->rd_rel->relpersistence,
 							forkNum, blockNum, mode, strategy, &hit);
 	if (hit)
 		pgstat_count_buffer_hit(reln);
@@ -794,7 +795,7 @@ ReadBufferWithoutRelcache(RelFileLocator rlocator, ForkNumber forkNum,
 
 	SMgrRelation smgr = smgropen(rlocator, InvalidBackendId);
 
-	return ReadBuffer_common(smgr, permanent ? RELPERSISTENCE_PERMANENT :
+	return ReadBuffer_common(NULL, smgr, permanent ? RELPERSISTENCE_PERMANENT :
 							 RELPERSISTENCE_UNLOGGED, forkNum, blockNum,
 							 mode, strategy, &hit);
 }
@@ -806,7 +807,7 @@ ReadBufferWithoutRelcache(RelFileLocator rlocator, ForkNumber forkNum,
  * *hit is set to true if the request was satisfied from shared buffer cache.
  */
 static Buffer
-ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
+ReadBuffer_common(Relation rel, SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 				  BlockNumber blockNum, ReadBufferMode mode,
 				  BufferAccessStrategy strategy, bool *hit)
 {
@@ -1038,6 +1039,18 @@ ReadBuffer_common(SMgrRelation smgr, char relpersistence, ForkNumber forkNum,
 									blockNum,
 									relpath(smgr->smgr_rlocator, forkNum))));
 			}
+
+			if (PageGetPageLayoutVersion(bufBlock) != PG_PAGE_LAYOUT_VERSION &&
+				!PageIsNew((Page) bufBlock))
+			{
+				Buffer		buf = BufferDescriptorGetBuffer(bufHdr);
+
+				LWLockAcquire(BufferDescriptorGetContentLock(bufHdr), LW_EXCLUSIVE);
+				/* Check for no concurrent changes */
+				if (PageGetPageLayoutVersion(bufBlock) != PG_PAGE_LAYOUT_VERSION)
+					convert_page(rel, bufBlock, buf, blockNum);
+				LWLockRelease(BufferDescriptorGetContentLock(bufHdr));
+			}
 		}
 	}
 
@@ -4115,6 +4128,64 @@ MarkBufferDirtyHint(Buffer buffer, bool buffer_std)
 	}
 }
 
+/*
+ * Mark buffer as converted - ie its format is changed without logical changes.
+ *
+ * It will override `full_page_write` GUC setting in XLogRecordAssemble.
+ */
+void
+MarkBufferConverted(Buffer buffer, bool converted)
+{
+	BufferDesc *bufHdr;
+	uint32		buf_state;
+	bool		has_mark;
+
+	if (!BufferIsValid(buffer))
+		elog(ERROR, "bad buffer ID: %d", buffer);
+
+	Assert(!BufferIsLocal(buffer));
+
+	bufHdr = GetBufferDescriptor(buffer - 1);
+
+	Assert(GetPrivateRefCount(buffer) > 0);
+	if (converted)
+	{
+		/* here, either share or exclusive lock is OK */
+		Assert(LWLockHeldByMe(BufferDescriptorGetContentLock(bufHdr)));
+	}
+
+	buf_state = pg_atomic_read_u32(&bufHdr->state);
+	has_mark = (buf_state & BM_CONVERTED) != 0;
+	if (converted == has_mark)
+		return;
+
+	buf_state = LockBufHdr(bufHdr);
+	buf_state &= ~BM_CONVERTED;
+	if (converted)
+		buf_state |= BM_CONVERTED;
+	UnlockBufHdr(bufHdr, buf_state);
+}
+
+bool
+IsBufferConverted(Buffer buffer)
+{
+
+	BufferDesc *bufHdr;
+	uint32		buf_state;
+
+	if (!BufferIsValid(buffer))
+		elog(ERROR, "bad buffer ID: %d", buffer);
+
+	Assert(!BufferIsLocal(buffer));
+
+	bufHdr = GetBufferDescriptor(buffer - 1);
+
+	Assert(GetPrivateRefCount(buffer) > 0);
+
+	buf_state = pg_atomic_read_u32(&bufHdr->state);
+	return (buf_state & BM_CONVERTED) != 0;
+}
+
 /*
  * Release buffer content locks for shared buffers.
  *
diff --git a/src/backend/storage/buffer/heap_convert.c b/src/backend/storage/buffer/heap_convert.c
new file mode 100644
index 0000000000..2f2e639f34
--- /dev/null
+++ b/src/backend/storage/buffer/heap_convert.c
@@ -0,0 +1,547 @@
+/*-------------------------------------------------------------------------
+ *
+ * heap_convert.c
+ *	  Heap page converter from 32bit to 64bit xid format
+ *
+ *	Copyright (c) 2015-2022, Postgres Professional
+ *
+ * IDENTIFICATION
+ *	  src/backend/storage/buffer/heap_convert.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "access/generic_xlog.h"
+#include "access/heapam.h"
+#include "access/multixact.h"
+#include "catalog/catalog.h"
+#include "storage/bufmgr.h"
+#include "storage/checksum.h"
+
+static void repack_heap_tuples(Relation rel, Page page, Buffer buf,
+							   BlockNumber blkno, bool double_xmax);
+
+/*
+ * itemoffcompare
+ *		Sorting support for repack_tuples()
+ */
+int
+itemoffcompare(const void *item1, const void *item2)
+{
+	/* Sort in decreasing itemoff order */
+	return ((ItemIdCompactData *) item2)->itemoff -
+		   ((ItemIdCompactData *) item1)->itemoff;
+}
+
+/*
+ * Lazy page conversion from 32-bit to 64-bit XID at first read.
+ */
+void
+convert_page(Relation rel, Page page, Buffer buf, BlockNumber blkno)
+{
+	static unsigned		logcnt = 0;
+	bool				logit;
+	PageHeader			hdr = (PageHeader) page;
+	GenericXLogState   *state = NULL;
+	uint16				checksum;
+	bool				try_double_xmax;
+
+	/* Not during XLog replaying */
+	Assert(rel != NULL);
+
+	/* Verify checksum */
+	if (hdr->pd_checksum)
+	{
+		checksum = pg_checksum_page((char *) page, blkno);
+		if (checksum != hdr->pd_checksum)
+			ereport(ERROR,
+					(errcode(ERRCODE_INDEX_CORRUPTED),
+					 errmsg("page verification failed, calculated checksum %u but expected %u",
+							checksum, hdr->pd_checksum)));
+	}
+
+	/*
+	 * We occasionally force logging of page conversion, so never-changed
+	 * pages are converted in the end. FORCE_LOG_EVERY is chosen arbitrarily
+	 * to log neither too much nor too little.
+	 */
+#define FORCE_LOG_EVERY 128
+	logit = !RecoveryInProgress() && XLogIsNeeded() && RelationNeedsWAL(rel);
+	logit = logit && (++logcnt % FORCE_LOG_EVERY) == 0;
+	if (logit)
+	{
+		state = GenericXLogStart(rel);
+		page = GenericXLogRegisterBuffer(state, buf,
+										 GENERIC_XLOG_FULL_IMAGE);
+		hdr = (PageHeader) page;
+	}
+
+#ifdef USE_ASSERT_CHECKING
+	if (!logit)
+	{
+		/* Not already converted */
+		Assert(PageGetPageLayoutVersion(page) != PG_PAGE_LAYOUT_VERSION);
+		/* Page in 32-bit xid format should not have PageSpecial. */
+		Assert(PageGetSpecialSize(hdr) == 0);
+	}
+#endif
+
+	switch (rel->rd_rel->relkind)
+	{
+		case 't':
+			try_double_xmax = hdr->pd_upper - hdr->pd_lower <
+									MAXALIGN(sizeof(ToastPageSpecialData));
+			repack_heap_tuples(rel, page, buf, blkno, try_double_xmax);
+			break;
+		case 'r':
+		case 'p':
+		case 'm':
+			try_double_xmax = hdr->pd_upper - hdr->pd_lower <
+									MAXALIGN(sizeof(HeapPageSpecialData));
+			repack_heap_tuples(rel, page, buf, blkno, try_double_xmax);
+			break;
+		case 'i':
+			/* no need to convert index */
+		case 'S':
+			/* no real need to convert sequences */
+			break;
+		default:
+			ereport(ERROR,
+					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+					 errmsg("conversion for relation \"%s\" cannot be done",
+							RelationGetRelationName(rel)),
+					 errdetail_relkind_not_supported(rel->rd_rel->relkind)));
+	}
+
+	hdr->pd_checksum = pg_checksum_page((char *) page, blkno);
+
+	PageSetPageSizeAndVersion((hdr), PageGetPageSize(hdr),
+							  PG_PAGE_LAYOUT_VERSION);
+
+	if (logit)
+	{
+		/*
+		 * Finish logging buffer conversion and mark buffer as dirty.
+		 */
+		Assert(state != NULL);
+		MarkBufferDirty(buf);
+		GenericXLogFinish(state);
+	}
+	else
+	{
+		/*
+		 * Otherwise, it will be logged with full-page-write record on first
+		 * actual change.
+		 */
+		MarkBufferConverted(buf, true);
+	}
+}
+
+/*
+ * Convert xmin and xmax in a tuple.
+ * This also considers special cases: "double xmax" page format and multixact
+ * in xmax.
+ */
+static void
+convert_heap_tuple_xids(HeapTupleHeader tuple, TransactionId xid_base,
+						MultiXactId multi_base, bool double_xmax)
+{
+	/* Convert xmin */
+	if (double_xmax)
+	{
+		/* Prepare tuple for "double xmax" page format */
+		tuple->t_infomask |= HEAP_XMIN_FROZEN;
+		tuple->t_choice.t_heap.t_xmin = 0;
+	}
+	else
+	{
+		TransactionId xmin = tuple->t_choice.t_heap.t_xmin;
+
+		if (TransactionIdIsNormal(xmin))
+		{
+			if (HeapTupleHeaderXminFrozen(tuple))
+				tuple->t_choice.t_heap.t_xmin = FrozenTransactionId;
+			else if (HeapTupleHeaderXminInvalid(tuple))
+				tuple->t_choice.t_heap.t_xmin = InvalidTransactionId;
+			else
+			{
+				Assert(xmin >= xid_base + FirstNormalTransactionId);
+				/* Subtract xid_base from normal xmin */
+				tuple->t_choice.t_heap.t_xmin = xmin - xid_base;
+			}
+		}
+	}
+
+	/* If tuple has multixact flag, handle mxid wraparound */
+	if ((tuple->t_infomask & HEAP_XMAX_IS_MULTI) &&
+		!(tuple->t_infomask & HEAP_XMAX_INVALID))
+	{
+		MultiXactId mxid = tuple->t_choice.t_heap.t_xmax;
+
+		/* Handle mxid wraparound */
+		if (mxid < multi_base)
+		{
+			mxid += ((MultiXactId) 1 << 32) - FirstMultiXactId;
+			Assert(mxid >= multi_base);
+		}
+
+		if (double_xmax)
+		{
+			/* Save converted mxid into "double xmax" format */
+			HeapTupleHeaderSetDoubleXmax(tuple, mxid);
+		}
+		else
+		{
+			/*
+			 * Save converted mxid offset relative to (minmxid - 1), which
+			 * will be page's mxid base.
+			 */
+			Assert(mxid - multi_base + FirstMultiXactId <= PG_UINT32_MAX);
+			tuple->t_choice.t_heap.t_xmax =
+				(uint32) (mxid - multi_base + FirstMultiXactId);
+		}
+	}
+	/* Convert xmax */
+	else if (!(tuple->t_infomask & HEAP_XMAX_INVALID))
+	{
+		TransactionId xmax = tuple->t_choice.t_heap.t_xmax;
+
+		if (double_xmax)
+		{
+			/* Save converted xmax into "double xmax" format */
+			HeapTupleHeaderSetDoubleXmax(tuple, xmax);
+		}
+		else if (TransactionIdIsNormal(xmax))
+		{
+			/* Subtract xid_base from normal xmax */
+			Assert(xmax >= xid_base + FirstNormalTransactionId);
+			tuple->t_choice.t_heap.t_xmax = xmax - xid_base;
+		}
+	}
+	else
+	{
+		if (double_xmax)
+			HeapTupleHeaderSetDoubleXmax(tuple, InvalidTransactionId);
+		else
+			tuple->t_choice.t_heap.t_xmax = InvalidTransactionId;
+	}
+}
+
+/*
+ * Correct page xmin/xmax based on tuple xmin/xmax values.
+ */
+static void
+compute_xid_min_max(HeapTuple tuple, MultiXactId multi_base,
+					TransactionId *xid_min, TransactionId *xid_max,
+					MultiXactId *multi_min, MultiXactId *multi_max)
+{
+	/* xmin */
+	if (!HeapTupleHeaderXminInvalid(tuple->t_data) &&
+		!HeapTupleHeaderXminFrozen(tuple->t_data))
+	{
+		TransactionId xid = HeapTupleGetRawXmin(tuple);
+
+		if (TransactionIdIsNormal(xid))
+		{
+			*xid_max = Max(*xid_max, xid);
+			*xid_min = Min(*xid_min, xid);
+		}
+	}
+
+	/* xmax */
+	if (!(tuple->t_data->t_infomask & HEAP_XMAX_INVALID))
+	{
+		TransactionId xid;
+
+		if (tuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI)
+		{
+			MultiXactId mxid = HeapTupleGetRawXmax(tuple);
+
+			Assert(MultiXactIdIsValid(mxid));
+
+			/* Handle mxid wraparound */
+			if (mxid < multi_base)
+			{
+				mxid += ((MultiXactId) 1 << 32) - FirstMultiXactId;
+				Assert(mxid >= multi_base);
+			}
+
+			*multi_max = Max(*multi_max, mxid);
+			*multi_min = Min(*multi_min, mxid);
+
+			/*
+			 * Also take into account hidden update xid, which can be
+			 * extracted by the vacuum.
+			 */
+			if (tuple->t_data->t_infomask & HEAP_XMAX_LOCK_ONLY)
+				xid = InvalidTransactionId;
+			else
+				xid = HeapTupleGetUpdateXid(tuple);
+		}
+		else
+		{
+			xid = HeapTupleGetRawXmax(tuple);
+		}
+
+		if (TransactionIdIsNormal(xid))
+		{
+			*xid_max = Max(*xid_max, xid);
+			*xid_min = Min(*xid_min, xid);
+		}
+	}
+}
+
+/*
+ * Returns true if both:
+ *  - xid_max: an uppper boundary of xmin's and xmax'es of all tuples on a page
+ *  - xid_min: a lower boundary of xmin's and xmax'es of all tuples on a page
+ *    can be expressed by 32-bit number relative to page's xid_base/multi_base
+ *    or invalid.
+ *
+ * True value effectively means that these tuples can be directly put on one
+ * page in 64-xid format.
+ */
+static inline bool
+xids_fit_page(TransactionId xid_min, TransactionId xid_max,
+			  MultiXactId multi_min, MultiXactId multi_max)
+{
+	bool xid_max_fits = false;
+	bool multi_max_fits = false;
+
+	if (xid_max == InvalidTransactionId)
+		xid_max_fits = true;
+
+	if (xid_max - xid_min <= MaxShortTransactionId - FirstNormalTransactionId)
+		xid_max_fits = true;
+
+	if (multi_max == InvalidMultiXactId)
+		multi_max_fits = true;
+
+	if (multi_max - multi_min <= MaxShortTransactionId - FirstMultiXactId)
+		multi_max_fits = true;
+
+	return xid_max_fits && multi_max_fits;
+}
+
+/*
+ * Set "base" for page in 64-bit XID format.
+ *
+ * This should not be called for double xmax pages. They do not have place for
+ * page special.
+ */
+static inline void
+heap_page_set_base(Page page,
+				   TransactionId xid_min, TransactionId xid_max,
+				   MultiXactId multi_min, MultiXactId multi_max,
+				   TransactionId *xid_base, MultiXactId *multi_base,
+				   bool is_toast)
+{
+	PageHeader			hdr = (PageHeader) page;
+
+	if (xid_max != InvalidTransactionId)
+		*xid_base = xid_min - FirstNormalTransactionId;
+	else
+		*xid_base = InvalidTransactionId;
+
+	if (multi_max != InvalidMultiXactId)
+		*multi_base = multi_min - FirstMultiXactId;
+	else
+		*multi_base = InvalidMultiXactId;
+
+	if (is_toast)
+	{
+		ToastPageSpecial		special;
+
+		hdr->pd_special = BLCKSZ - MAXALIGN(sizeof(ToastPageSpecialData));
+		special = ToastPageGetSpecial(page);
+		special->pd_xid_base = *xid_base;
+	}
+	else
+	{
+		HeapPageSpecial		special;
+
+		hdr->pd_special = BLCKSZ - MAXALIGN(sizeof(HeapPageSpecialData));
+		special = HeapPageGetSpecial(page);
+		special->pd_xid_base = *xid_base;
+		special->pd_multi_base = *multi_base;
+	}
+}
+
+/*
+ * repack_heap_tuples
+ *		Convert heap page format reusing space of dead tuples
+ */
+static void
+repack_heap_tuples(Relation rel, Page page, Buffer buf, BlockNumber blkno,
+				   bool try_double_xmax)
+{
+	ItemIdCompactData	items[MaxHeapTuplesPerPage];
+	ItemIdCompact		itemPtr = items;
+	int					nitems = 0,
+						maxoff = PageGetMaxOffsetNumber(page),
+						idx,
+						occupied_space = 0;
+	Offset				upper;
+	bool				double_xmax,
+						special_fits,
+						toast;
+	PageHeader			hdr = (PageHeader) page,
+						new_hdr;
+	char				new_page[BLCKSZ] = {0};
+	MultiXactId			multi_base = rel->rd_rel->relminmxid,
+						multi_min = MaxMultiXactId,
+						multi_max = InvalidMultiXactId;
+	TransactionId		xid_base = rel->rd_rel->relfrozenxid,
+						xid_min = MaxTransactionId,
+						xid_max = InvalidTransactionId;
+
+	toast = IsToastRelation(rel);
+
+	if (TransactionIdIsNormal(hdr->pd_prune_xid))
+		xid_min = xid_max = hdr->pd_prune_xid;
+
+	for (idx = 0; idx < maxoff; idx++)
+	{
+		HeapTupleData		tuple;
+		ItemId				lp;
+
+		lp = PageGetItemId(page, idx + 1);
+
+		/* Skip redirects and items without storage */
+		if (!ItemIdHasStorage(lp))
+			continue;
+
+		/* Build in-memory tuple representation */
+		tuple.t_tableOid = 1;	/* doesn't matter in this case */
+		tuple.t_data = (HeapTupleHeader) PageGetItem(page, lp);
+		HeapTupleCopyHeaderXids(&tuple);
+		tuple.t_len = ItemIdGetLength(lp);
+		ItemPointerSet(&(tuple.t_self), blkno, ItemIdGetOffset(lp));
+
+		/*
+		 * This is only needed to determine whether tuple is HEAPTUPLE_DEAD or
+		 * HEAPTUPLE_RECENTLY_DEAD. And since this is the first time we read
+		 * page after pg_upgrade, it cannot be HEAPTUPLE_RECENTLY_DEAD. See
+		 * HeapTupleSatisfiesVacuum() for details
+		 */
+		if (try_double_xmax &&
+			HeapTupleSatisfiesVacuum(&tuple,
+									 (TransactionId) 1 << 32, buf) == HEAPTUPLE_DEAD)
+		{
+			ItemIdSetDead(lp);
+		}
+
+		if (ItemIdIsNormal(lp) && ItemIdHasStorage(lp))
+		{
+			itemPtr->offsetindex = idx;
+			itemPtr->itemoff = ItemIdGetOffset(lp);
+			if (unlikely(itemPtr->itemoff < hdr->pd_upper ||
+						 itemPtr->itemoff >= hdr->pd_special))
+			{
+				ereport(ERROR,
+						(errcode(ERRCODE_DATA_CORRUPTED),
+						 errmsg("corrupted item pointer: %u",
+								itemPtr->itemoff)));
+			}
+
+			itemPtr->alignedlen = MAXALIGN(ItemIdGetLength(lp));
+			occupied_space += itemPtr->alignedlen;
+			nitems++;
+			itemPtr++;
+			if (try_double_xmax)
+			{
+				HeapTupleSetXmin(&tuple, FrozenTransactionId);
+				HeapTupleHeaderSetXminFrozen(tuple.t_data);
+			}
+
+			compute_xid_min_max(&tuple, multi_base,
+								&xid_min, &xid_max,
+								&multi_min, &multi_max);
+		}
+	}
+
+	/* Write new header */
+	new_hdr = (PageHeader) new_page;
+	*new_hdr = *hdr;
+	new_hdr->pd_lower = SizeOfPageHeaderData + maxoff * sizeof(ItemIdData);
+
+	if (toast)
+		special_fits = BLCKSZ - new_hdr->pd_lower - occupied_space >=
+						sizeof(ToastPageSpecialData);
+	else
+		special_fits = BLCKSZ - new_hdr->pd_lower - occupied_space >=
+						sizeof(HeapPageSpecialData);
+
+	double_xmax = !special_fits ||
+				  !xids_fit_page(xid_min, xid_max, multi_min, multi_max);
+
+	if (!double_xmax)
+	{
+		Assert(xid_max == InvalidTransactionId || xid_max >= xid_min);
+		Assert(multi_max == InvalidMultiXactId || multi_max >= multi_min);
+
+		heap_page_set_base(new_page,
+						   xid_min, xid_max,
+						   multi_min, multi_max,
+						   &xid_base, &multi_base,
+						   toast);
+
+		HeapPageSetPruneXid(new_page, new_hdr->pd_prune_xid, toast);
+	}
+	else
+	{
+		/* No space for special area, switch to "double xmax" format */
+		elog(DEBUG2, "convert heap page %u of relation \"%s\" to double xmax format",
+			 blkno, RelationGetRelationName(rel));
+
+		if (try_double_xmax)
+		{
+			xid_base = InvalidTransactionId;
+			multi_base = InvalidMultiXactId;
+		}
+		else
+		{
+			repack_heap_tuples(rel, page, buf, blkno, true);
+			return;
+		}
+	}
+
+	/* Copy ItemIds with an offset */
+	memcpy((char *) new_page + SizeOfPageHeaderData,
+		   (char *) page + SizeOfPageHeaderData,
+		   hdr->pd_lower - SizeOfPageHeaderData);
+
+	/* Move live tuples */
+	upper = new_hdr->pd_special;
+	for (idx = 0; idx < nitems; idx++)
+	{
+		HeapTupleHeader		tuple;
+		ItemId				lp;
+
+		itemPtr = &items[idx];
+		lp = PageGetItemId(new_page, itemPtr->offsetindex + 1);
+		upper -= itemPtr->alignedlen;
+		occupied_space -= itemPtr->alignedlen;
+
+		memcpy((char *) new_page + upper,
+			   (char *) page + itemPtr->itemoff,
+			   itemPtr->alignedlen);
+
+		tuple = (HeapTupleHeader) (((char *) new_page) + upper);
+
+		convert_heap_tuple_xids(tuple, xid_base, multi_base, double_xmax);
+
+		lp->lp_off = upper;
+	}
+
+	Assert(occupied_space == 0);
+
+	new_hdr->pd_upper = upper;
+	if (new_hdr->pd_lower > new_hdr->pd_upper)
+		elog(ERROR, "cannot convert block %u of relation \"%s\"",
+			 blkno, RelationGetRelationName(rel));
+
+	memcpy(page, new_page, BLCKSZ);
+}
diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c
index 1c9cb21043..4e5b2ffdfb 100644
--- a/src/backend/storage/ipc/procarray.c
+++ b/src/backend/storage/ipc/procarray.c
@@ -66,7 +66,7 @@
 #include "utils/rel.h"
 #include "utils/snapmgr.h"
 
-#define UINT32_ACCESS_ONCE(var)		 ((uint32)(*((volatile uint32 *)&(var))))
+#define UINT64_ACCESS_ONCE(var)		 ((uint64)(*((volatile uint64 *)&(var))))
 
 /* Our shared memory area */
 typedef struct ProcArrayStruct
@@ -355,9 +355,6 @@ static inline void ProcArrayEndTransactionInternal(PGPROC *proc, TransactionId l
 static void ProcArrayGroupClearXid(PGPROC *proc, TransactionId latestXid);
 static void MaintainLatestCompletedXid(TransactionId latestXid);
 static void MaintainLatestCompletedXidRecovery(TransactionId latestXid);
-
-static inline FullTransactionId FullXidRelativeTo(FullTransactionId rel,
-												  TransactionId xid);
 static void GlobalVisUpdateApply(ComputeXidHorizonsResult *horizons);
 
 /*
@@ -516,7 +513,8 @@ ProcArrayAdd(PGPROC *proc)
 
 	arrayP->pgprocnos[index] = proc->pgprocno;
 	proc->pgxactoff = index;
-	ProcGlobal->xids[index] = proc->xid;
+	pg_atomic_write_u64(&ProcGlobal->xids[index],
+						pg_atomic_read_u64(&proc->xid));
 	ProcGlobal->subxidStates[index] = proc->subxidStatus;
 	ProcGlobal->statusFlags[index] = proc->statusFlags;
 
@@ -576,7 +574,7 @@ ProcArrayRemove(PGPROC *proc, TransactionId latestXid)
 
 	if (TransactionIdIsValid(latestXid))
 	{
-		Assert(TransactionIdIsValid(ProcGlobal->xids[myoff]));
+		Assert(TransactionIdIsValid(pg_atomic_read_u64(&ProcGlobal->xids[myoff])));
 
 		/* Advance global latestCompletedXid while holding the lock */
 		MaintainLatestCompletedXid(latestXid);
@@ -584,17 +582,17 @@ ProcArrayRemove(PGPROC *proc, TransactionId latestXid)
 		/* Same with xactCompletionCount  */
 		ShmemVariableCache->xactCompletionCount++;
 
-		ProcGlobal->xids[myoff] = InvalidTransactionId;
+		pg_atomic_write_u64(&ProcGlobal->xids[myoff], InvalidTransactionId);
 		ProcGlobal->subxidStates[myoff].overflowed = false;
 		ProcGlobal->subxidStates[myoff].count = 0;
 	}
 	else
 	{
 		/* Shouldn't be trying to remove a live transaction here */
-		Assert(!TransactionIdIsValid(ProcGlobal->xids[myoff]));
+		Assert(!TransactionIdIsValid(pg_atomic_read_u64(&(ProcGlobal->xids[myoff]))));
 	}
 
-	Assert(!TransactionIdIsValid(ProcGlobal->xids[myoff]));
+	Assert(!TransactionIdIsValid(pg_atomic_read_u64(&(ProcGlobal->xids[myoff]))));
 	Assert(ProcGlobal->subxidStates[myoff].count == 0);
 	Assert(ProcGlobal->subxidStates[myoff].overflowed == false);
 
@@ -640,7 +638,6 @@ ProcArrayRemove(PGPROC *proc, TransactionId latestXid)
 	LWLockRelease(ProcArrayLock);
 }
 
-
 /*
  * ProcArrayEndTransaction -- mark a transaction as no longer running
  *
@@ -665,7 +662,7 @@ ProcArrayEndTransaction(PGPROC *proc, TransactionId latestXid)
 		 * else is taking a snapshot.  See discussion in
 		 * src/backend/access/transam/README.
 		 */
-		Assert(TransactionIdIsValid(proc->xid));
+		Assert(TransactionIdIsValid(pg_atomic_read_u64(&proc->xid)));
 
 		/*
 		 * If we can immediately acquire ProcArrayLock, we clear our own XID
@@ -687,12 +684,12 @@ ProcArrayEndTransaction(PGPROC *proc, TransactionId latestXid)
 		 * anyone else's calculation of a snapshot.  We might change their
 		 * estimate of global xmin, but that's OK.
 		 */
-		Assert(!TransactionIdIsValid(proc->xid));
+		Assert(!TransactionIdIsValid(pg_atomic_read_u64(&proc->xid)));
 		Assert(proc->subxidStatus.count == 0);
 		Assert(!proc->subxidStatus.overflowed);
 
 		proc->lxid = InvalidLocalTransactionId;
-		proc->xmin = InvalidTransactionId;
+		pg_atomic_write_u64(&proc->xmin, InvalidTransactionId);
 
 		/* be sure this is cleared in abort */
 		proc->delayChkptFlags = 0;
@@ -728,13 +725,14 @@ ProcArrayEndTransactionInternal(PGPROC *proc, TransactionId latestXid)
 	 * processes' PGPROC entries.
 	 */
 	Assert(LWLockHeldByMeInMode(ProcArrayLock, LW_EXCLUSIVE));
-	Assert(TransactionIdIsValid(ProcGlobal->xids[pgxactoff]));
-	Assert(ProcGlobal->xids[pgxactoff] == proc->xid);
+	Assert(TransactionIdIsValid(pg_atomic_read_u64(&ProcGlobal->xids[pgxactoff])));
+	Assert(pg_atomic_read_u64(&ProcGlobal->xids[pgxactoff]) ==
+		   pg_atomic_read_u64(&proc->xid));
 
-	ProcGlobal->xids[pgxactoff] = InvalidTransactionId;
-	proc->xid = InvalidTransactionId;
+	pg_atomic_write_u64(&ProcGlobal->xids[pgxactoff], InvalidTransactionId);
+	pg_atomic_write_u64(&proc->xid, InvalidTransactionId);
 	proc->lxid = InvalidLocalTransactionId;
-	proc->xmin = InvalidTransactionId;
+	pg_atomic_write_u64(&proc->xmin, InvalidTransactionId);
 
 	/* be sure this is cleared in abort */
 	proc->delayChkptFlags = 0;
@@ -787,7 +785,7 @@ ProcArrayGroupClearXid(PGPROC *proc, TransactionId latestXid)
 	uint32		wakeidx;
 
 	/* We should definitely have an XID to clear. */
-	Assert(TransactionIdIsValid(proc->xid));
+	Assert(TransactionIdIsValid(pg_atomic_read_u64(&proc->xid)));
 
 	/* Add ourselves to the list of processes needing a group XID clear. */
 	proc->procArrayGroupMember = true;
@@ -916,11 +914,11 @@ ProcArrayClearTransaction(PGPROC *proc)
 
 	pgxactoff = proc->pgxactoff;
 
-	ProcGlobal->xids[pgxactoff] = InvalidTransactionId;
-	proc->xid = InvalidTransactionId;
+	pg_atomic_write_u64(&ProcGlobal->xids[pgxactoff], InvalidTransactionId);
+	pg_atomic_write_u64(&proc->xid, InvalidTransactionId);
 
 	proc->lxid = InvalidLocalTransactionId;
-	proc->xmin = InvalidTransactionId;
+	pg_atomic_write_u64(&proc->xmin, InvalidTransactionId);
 	proc->recoveryConflictPending = false;
 
 	Assert(!(proc->statusFlags & PROC_VACUUM_STATE_MASK));
@@ -964,8 +962,7 @@ MaintainLatestCompletedXid(TransactionId latestXid)
 
 	if (TransactionIdPrecedes(XidFromFullTransactionId(cur_latest), latestXid))
 	{
-		ShmemVariableCache->latestCompletedXid =
-			FullXidRelativeTo(cur_latest, latestXid);
+		ShmemVariableCache->latestCompletedXid = FullTransactionIdFromXid(latestXid);
 	}
 
 	Assert(IsBootstrapProcessingMode() ||
@@ -979,7 +976,6 @@ static void
 MaintainLatestCompletedXidRecovery(TransactionId latestXid)
 {
 	FullTransactionId cur_latest = ShmemVariableCache->latestCompletedXid;
-	FullTransactionId rel;
 
 	Assert(AmStartupProcess() || !IsUnderPostmaster);
 	Assert(LWLockHeldByMe(ProcArrayLock));
@@ -989,14 +985,12 @@ MaintainLatestCompletedXidRecovery(TransactionId latestXid)
 	 * latestCompletedXid to be initialized in recovery. But in recovery it's
 	 * safe to access nextXid without a lock for the startup process.
 	 */
-	rel = ShmemVariableCache->nextXid;
 	Assert(FullTransactionIdIsValid(ShmemVariableCache->nextXid));
 
 	if (!FullTransactionIdIsValid(cur_latest) ||
 		TransactionIdPrecedes(XidFromFullTransactionId(cur_latest), latestXid))
 	{
-		ShmemVariableCache->latestCompletedXid =
-			FullXidRelativeTo(rel, latestXid);
+		ShmemVariableCache->latestCompletedXid = FullTransactionIdFromXid(latestXid);
 	}
 
 	Assert(FullTransactionIdIsNormal(ShmemVariableCache->latestCompletedXid));
@@ -1374,7 +1368,7 @@ bool
 TransactionIdIsInProgress(TransactionId xid)
 {
 	static TransactionId *xids = NULL;
-	static TransactionId *other_xids;
+	static pg_atomic_uint64 *other_xids;
 	XidCacheStatus *other_subxidstates;
 	int			nxids = 0;
 	ProcArrayStruct *arrayP = procArray;
@@ -1470,7 +1464,7 @@ TransactionIdIsInProgress(TransactionId xid)
 			continue;
 
 		/* Fetch xid just once - see GetNewTransactionId */
-		pxid = UINT32_ACCESS_ONCE(other_xids[pgxactoff]);
+		pxid = pg_atomic_read_u64(&(other_xids[pgxactoff]));
 
 		if (!TransactionIdIsValid(pxid))
 			continue;
@@ -1502,7 +1496,7 @@ TransactionIdIsInProgress(TransactionId xid)
 		for (j = pxids - 1; j >= 0; j--)
 		{
 			/* Fetch xid just once - see GetNewTransactionId */
-			TransactionId cxid = UINT32_ACCESS_ONCE(proc->subxids.xids[j]);
+			TransactionId cxid = UINT64_ACCESS_ONCE(proc->subxids.xids[j]);
 
 			if (TransactionIdEquals(cxid, xid))
 			{
@@ -1612,7 +1606,7 @@ TransactionIdIsActive(TransactionId xid)
 {
 	bool		result = false;
 	ProcArrayStruct *arrayP = procArray;
-	TransactionId *other_xids = ProcGlobal->xids;
+	pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 	int			i;
 
 	/*
@@ -1631,7 +1625,7 @@ TransactionIdIsActive(TransactionId xid)
 		TransactionId pxid;
 
 		/* Fetch xid just once - see GetNewTransactionId */
-		pxid = UINT32_ACCESS_ONCE(other_xids[i]);
+		pxid = pg_atomic_read_u64(&(other_xids[i]));
 
 		if (!TransactionIdIsValid(pxid))
 			continue;
@@ -1717,7 +1711,7 @@ ComputeXidHorizons(ComputeXidHorizonsResult *h)
 	ProcArrayStruct *arrayP = procArray;
 	TransactionId kaxmin;
 	bool		in_recovery = RecoveryInProgress();
-	TransactionId *other_xids = ProcGlobal->xids;
+	pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 
 	/* inferred after ProcArrayLock is released */
 	h->catalog_oldest_nonremovable = InvalidTransactionId;
@@ -1733,7 +1727,8 @@ ComputeXidHorizons(ComputeXidHorizonsResult *h)
 	 * additions.
 	 */
 	{
-		TransactionId initial;
+		TransactionId initial,
+					  xid;
 
 		initial = XidFromFullTransactionId(h->latest_completed);
 		Assert(TransactionIdIsValid(initial));
@@ -1755,8 +1750,9 @@ ComputeXidHorizons(ComputeXidHorizonsResult *h)
 		 * definition, can't be any newer changes in the temp table than
 		 * latestCompletedXid.
 		 */
-		if (TransactionIdIsValid(MyProc->xid))
-			h->temp_oldest_nonremovable = MyProc->xid;
+		xid = pg_atomic_read_u64(&MyProc->xid);
+		if (TransactionIdIsValid(xid))
+			h->temp_oldest_nonremovable = xid;
 		else
 			h->temp_oldest_nonremovable = initial;
 	}
@@ -1778,8 +1774,8 @@ ComputeXidHorizons(ComputeXidHorizonsResult *h)
 		TransactionId xmin;
 
 		/* Fetch xid just once - see GetNewTransactionId */
-		xid = UINT32_ACCESS_ONCE(other_xids[index]);
-		xmin = UINT32_ACCESS_ONCE(proc->xmin);
+		xid = pg_atomic_read_u64(&(other_xids[index]));
+		xmin = pg_atomic_read_u64(&proc->xmin);
 
 		/*
 		 * Consider both the transaction's Xmin, and its Xid.
@@ -2154,8 +2150,8 @@ GetSnapshotDataReuse(Snapshot snapshot)
 	 * requirement that concurrent GetSnapshotData() calls yield the same
 	 * xmin.
 	 */
-	if (!TransactionIdIsValid(MyProc->xmin))
-		MyProc->xmin = TransactionXmin = snapshot->xmin;
+	if (!TransactionIdIsValid(pg_atomic_read_u64(&MyProc->xmin)))
+		pg_atomic_write_u64(&MyProc->xmin, TransactionXmin = snapshot->xmin);
 
 	RecentXmin = snapshot->xmin;
 	Assert(TransactionIdPrecedesOrEquals(TransactionXmin, RecentXmin));
@@ -2207,7 +2203,7 @@ Snapshot
 GetSnapshotData(Snapshot snapshot)
 {
 	ProcArrayStruct *arrayP = procArray;
-	TransactionId *other_xids = ProcGlobal->xids;
+	pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 	TransactionId xmin;
 	TransactionId xmax;
 	int			count = 0;
@@ -2270,8 +2266,8 @@ GetSnapshotData(Snapshot snapshot)
 
 	latest_completed = ShmemVariableCache->latestCompletedXid;
 	mypgxactoff = MyProc->pgxactoff;
-	myxid = other_xids[mypgxactoff];
-	Assert(myxid == MyProc->xid);
+	myxid = pg_atomic_read_u64(&other_xids[mypgxactoff]);
+	Assert(myxid == pg_atomic_read_u64(&MyProc->xid));
 
 	oldestxid = ShmemVariableCache->oldestXid;
 	curXactCompletionCount = ShmemVariableCache->xactCompletionCount;
@@ -2305,7 +2301,7 @@ GetSnapshotData(Snapshot snapshot)
 		for (int pgxactoff = 0; pgxactoff < numProcs; pgxactoff++)
 		{
 			/* Fetch xid just once - see GetNewTransactionId */
-			TransactionId xid = UINT32_ACCESS_ONCE(other_xids[pgxactoff]);
+			TransactionId xid = pg_atomic_read_u64(&(other_xids[pgxactoff]));
 			uint8		statusFlags;
 
 			Assert(allProcs[arrayP->pgprocnos[pgxactoff]].pgxactoff == pgxactoff);
@@ -2442,8 +2438,8 @@ GetSnapshotData(Snapshot snapshot)
 	replication_slot_xmin = procArray->replication_slot_xmin;
 	replication_slot_catalog_xmin = procArray->replication_slot_catalog_xmin;
 
-	if (!TransactionIdIsValid(MyProc->xmin))
-		MyProc->xmin = TransactionXmin = xmin;
+	if (!TransactionIdIsValid(pg_atomic_read_u64(&MyProc->xmin)))
+		pg_atomic_write_u64(&MyProc->xmin, TransactionXmin = xmin);
 
 	LWLockRelease(ProcArrayLock);
 
@@ -2455,12 +2451,7 @@ GetSnapshotData(Snapshot snapshot)
 		FullTransactionId def_vis_fxid_data;
 		FullTransactionId oldestfxid;
 
-		/*
-		 * Converting oldestXid is only safe when xid horizon cannot advance,
-		 * i.e. holding locks. While we don't hold the lock anymore, all the
-		 * necessary data has been gathered with lock held.
-		 */
-		oldestfxid = FullXidRelativeTo(latest_completed, oldestxid);
+		oldestfxid = FullTransactionIdFromXid(oldestxid);
 
 		/* apply vacuum_defer_cleanup_age */
 		def_vis_xid_data =
@@ -2483,8 +2474,8 @@ GetSnapshotData(Snapshot snapshot)
 		def_vis_xid =
 			TransactionIdOlder(replication_slot_catalog_xmin, def_vis_xid);
 
-		def_vis_fxid = FullXidRelativeTo(latest_completed, def_vis_xid);
-		def_vis_fxid_data = FullXidRelativeTo(latest_completed, def_vis_xid_data);
+		def_vis_fxid = FullTransactionIdFromXid(def_vis_xid);
+		def_vis_fxid_data = FullTransactionIdFromXid(def_vis_xid_data);
 
 		/*
 		 * Check if we can increase upper bound. As a previous
@@ -2503,7 +2494,7 @@ GetSnapshotData(Snapshot snapshot)
 		/* See temp_oldest_nonremovable computation in ComputeXidHorizons() */
 		if (TransactionIdIsNormal(myxid))
 			GlobalVisTempRels.definitely_needed =
-				FullXidRelativeTo(latest_completed, myxid);
+				FullTransactionIdFromXid(myxid);
 		else
 		{
 			GlobalVisTempRels.definitely_needed = latest_completed;
@@ -2610,7 +2601,7 @@ ProcArrayInstallImportedXmin(TransactionId xmin,
 		/*
 		 * Likewise, let's just make real sure its xmin does cover us.
 		 */
-		xid = UINT32_ACCESS_ONCE(proc->xmin);
+		xid = pg_atomic_read_u64(&proc->xmin);
 		if (!TransactionIdIsNormal(xid) ||
 			!TransactionIdPrecedesOrEquals(xid, xmin))
 			continue;
@@ -2621,7 +2612,7 @@ ProcArrayInstallImportedXmin(TransactionId xmin,
 		 * GetSnapshotData first, we'll be overwriting a valid xmin here, so
 		 * we don't check that.)
 		 */
-		MyProc->xmin = TransactionXmin = xmin;
+		pg_atomic_write_u64(&MyProc->xmin, TransactionXmin = xmin);
 
 		result = true;
 		break;
@@ -2665,7 +2656,7 @@ ProcArrayInstallRestoredXmin(TransactionId xmin, PGPROC *proc)
 	 * can't go backwards.  Also, make sure it's running in the same database,
 	 * so that the per-database xmin cannot go backwards.
 	 */
-	xid = UINT32_ACCESS_ONCE(proc->xmin);
+	xid = pg_atomic_read_u64(&proc->xmin);
 	if (proc->databaseId == MyDatabaseId &&
 		TransactionIdIsNormal(xid) &&
 		TransactionIdPrecedesOrEquals(xid, xmin))
@@ -2674,7 +2665,7 @@ ProcArrayInstallRestoredXmin(TransactionId xmin, PGPROC *proc)
 		 * Install xmin and propagate the statusFlags that affect how the
 		 * value is interpreted by vacuum.
 		 */
-		MyProc->xmin = TransactionXmin = xmin;
+		pg_atomic_write_u64(&MyProc->xmin, TransactionXmin = xmin);
 		MyProc->statusFlags = (MyProc->statusFlags & ~PROC_XMIN_FLAGS) |
 			(proc->statusFlags & PROC_XMIN_FLAGS);
 		ProcGlobal->statusFlags[MyProc->pgxactoff] = MyProc->statusFlags;
@@ -2725,7 +2716,7 @@ GetRunningTransactionData(void)
 	static RunningTransactionsData CurrentRunningXactsData;
 
 	ProcArrayStruct *arrayP = procArray;
-	TransactionId *other_xids = ProcGlobal->xids;
+	pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 	RunningTransactions CurrentRunningXacts = &CurrentRunningXactsData;
 	TransactionId latestCompletedXid;
 	TransactionId oldestRunningXid;
@@ -2784,7 +2775,7 @@ GetRunningTransactionData(void)
 		TransactionId xid;
 
 		/* Fetch xid just once - see GetNewTransactionId */
-		xid = UINT32_ACCESS_ONCE(other_xids[index]);
+		xid = pg_atomic_read_u64(&(other_xids[index]));
 
 		/*
 		 * We don't need to store transactions that don't have a TransactionId
@@ -2897,7 +2888,7 @@ TransactionId
 GetOldestActiveTransactionId(void)
 {
 	ProcArrayStruct *arrayP = procArray;
-	TransactionId *other_xids = ProcGlobal->xids;
+	pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 	TransactionId oldestRunningXid;
 	int			index;
 
@@ -2923,7 +2914,7 @@ GetOldestActiveTransactionId(void)
 		TransactionId xid;
 
 		/* Fetch xid just once - see GetNewTransactionId */
-		xid = UINT32_ACCESS_ONCE(other_xids[index]);
+		xid = pg_atomic_read_u64(&(other_xids[index]));
 
 		if (!TransactionIdIsNormal(xid))
 			continue;
@@ -3011,7 +3002,7 @@ GetOldestSafeDecodingTransactionId(bool catalogOnly)
 	 */
 	if (!recovery_in_progress)
 	{
-		TransactionId *other_xids = ProcGlobal->xids;
+		pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 
 		/*
 		 * Spin over procArray collecting min(ProcGlobal->xids[i])
@@ -3021,7 +3012,7 @@ GetOldestSafeDecodingTransactionId(bool catalogOnly)
 			TransactionId xid;
 
 			/* Fetch xid just once - see GetNewTransactionId */
-			xid = UINT32_ACCESS_ONCE(other_xids[index]);
+			xid = pg_atomic_read_u64(&(other_xids[index]));
 
 			if (!TransactionIdIsNormal(xid))
 				continue;
@@ -3216,7 +3207,7 @@ BackendXidGetPid(TransactionId xid)
 {
 	int			result = 0;
 	ProcArrayStruct *arrayP = procArray;
-	TransactionId *other_xids = ProcGlobal->xids;
+	pg_atomic_uint64 *other_xids = ProcGlobal->xids;
 	int			index;
 
 	if (xid == InvalidTransactionId)	/* never match invalid xid */
@@ -3229,7 +3220,7 @@ BackendXidGetPid(TransactionId xid)
 		int			pgprocno = arrayP->pgprocnos[index];
 		PGPROC	   *proc = &allProcs[pgprocno];
 
-		if (other_xids[index] == xid)
+		if (pg_atomic_read_u64(&other_xids[index]) == xid)
 		{
 			result = proc->pid;
 			break;
@@ -3310,7 +3301,7 @@ GetCurrentVirtualXIDs(TransactionId limitXmin, bool excludeXmin0,
 		if (allDbs || proc->databaseId == MyDatabaseId)
 		{
 			/* Fetch xmin just once - might change on us */
-			TransactionId pxmin = UINT32_ACCESS_ONCE(proc->xmin);
+			TransactionId pxmin = pg_atomic_read_u64(&proc->xmin);
 
 			if (excludeXmin0 && !TransactionIdIsValid(pxmin))
 				continue;
@@ -3405,7 +3396,7 @@ GetConflictingVirtualXIDs(TransactionId limitXmin, Oid dbOid)
 			proc->databaseId == dbOid)
 		{
 			/* Fetch xmin just once - can't change on us, but good coding */
-			TransactionId pxmin = UINT32_ACCESS_ONCE(proc->xmin);
+			TransactionId pxmin = pg_atomic_read_u64(&proc->xmin);
 
 			/*
 			 * We ignore an invalid pxmin because this means that backend has
@@ -3532,7 +3523,7 @@ MinimumActiveBackends(int min)
 			continue;			/* do not count deleted entries */
 		if (proc == MyProc)
 			continue;			/* do not count myself */
-		if (proc->xid == InvalidTransactionId)
+		if (pg_atomic_read_u64(&proc->xid) == InvalidTransactionId)
 			continue;			/* do not count if no XID assigned */
 		if (proc->pid == 0)
 			continue;			/* do not count prepared xacts */
@@ -4112,17 +4103,13 @@ static void
 GlobalVisUpdateApply(ComputeXidHorizonsResult *horizons)
 {
 	GlobalVisSharedRels.maybe_needed =
-		FullXidRelativeTo(horizons->latest_completed,
-						  horizons->shared_oldest_nonremovable);
+		FullTransactionIdFromXid(horizons->shared_oldest_nonremovable);
 	GlobalVisCatalogRels.maybe_needed =
-		FullXidRelativeTo(horizons->latest_completed,
-						  horizons->catalog_oldest_nonremovable);
+		FullTransactionIdFromXid(horizons->catalog_oldest_nonremovable);
 	GlobalVisDataRels.maybe_needed =
-		FullXidRelativeTo(horizons->latest_completed,
-						  horizons->data_oldest_nonremovable);
+		FullTransactionIdFromXid(horizons->data_oldest_nonremovable);
 	GlobalVisTempRels.maybe_needed =
-		FullXidRelativeTo(horizons->latest_completed,
-						  horizons->temp_oldest_nonremovable);
+		FullTransactionIdFromXid(horizons->temp_oldest_nonremovable);
 
 	/*
 	 * In longer running transactions it's possible that transactions we
@@ -4211,15 +4198,7 @@ GlobalVisTestIsRemovableXid(GlobalVisState *state, TransactionId xid)
 {
 	FullTransactionId fxid;
 
-	/*
-	 * Convert 32 bit argument to FullTransactionId. We can do so safely
-	 * because we know the xid has to, at the very least, be between
-	 * [oldestXid, nextFullXid), i.e. within 2 billion of xid. To avoid taking
-	 * a lock to determine either, we can just compare with
-	 * state->definitely_needed, which was based on those value at the time
-	 * the current snapshot was built.
-	 */
-	fxid = FullXidRelativeTo(state->definitely_needed, xid);
+	fxid = FullTransactionIdFromXid(xid);
 
 	return GlobalVisTestIsRemovableFullXid(state, fxid);
 }
@@ -4282,32 +4261,6 @@ GlobalVisCheckRemovableXid(Relation rel, TransactionId xid)
 	return GlobalVisTestIsRemovableXid(state, xid);
 }
 
-/*
- * Convert a 32 bit transaction id into 64 bit transaction id, by assuming it
- * is within MaxTransactionId / 2 of XidFromFullTransactionId(rel).
- *
- * Be very careful about when to use this function. It can only safely be used
- * when there is a guarantee that xid is within MaxTransactionId / 2 xids of
- * rel. That e.g. can be guaranteed if the caller assures a snapshot is
- * held by the backend and xid is from a table (where vacuum/freezing ensures
- * the xid has to be within that range), or if xid is from the procarray and
- * prevents xid wraparound that way.
- */
-static inline FullTransactionId
-FullXidRelativeTo(FullTransactionId rel, TransactionId xid)
-{
-	TransactionId rel_xid = XidFromFullTransactionId(rel);
-
-	Assert(TransactionIdIsValid(xid));
-	Assert(TransactionIdIsValid(rel_xid));
-
-	/* not guaranteed to find issues, but likely to catch mistakes */
-	AssertTransactionIdInAllowableRange(xid);
-
-	return FullTransactionIdFromU64(U64FromFullTransactionId(rel)
-									+ (int32) (xid - rel_xid));
-}
-
 
 /* ----------------------------------------------
  *		KnownAssignedTransactionIds sub-module
diff --git a/src/backend/storage/ipc/sinvaladt.c b/src/backend/storage/ipc/sinvaladt.c
index 59310b708f..bf712ba7ee 100644
--- a/src/backend/storage/ipc/sinvaladt.c
+++ b/src/backend/storage/ipc/sinvaladt.c
@@ -426,8 +426,8 @@ BackendIdGetTransactionIds(int backendID, TransactionId *xid, TransactionId *xmi
 
 		if (proc != NULL)
 		{
-			*xid = proc->xid;
-			*xmin = proc->xmin;
+			*xid = pg_atomic_read_u64(&proc->xid);
+			*xmin = pg_atomic_read_u64(&proc->xmin);
 		}
 	}
 
diff --git a/src/backend/storage/ipc/standby.c b/src/backend/storage/ipc/standby.c
index 99341c3e87..5f1bed8b56 100644
--- a/src/backend/storage/ipc/standby.c
+++ b/src/backend/storage/ipc/standby.c
@@ -37,7 +37,7 @@
 #include "utils/timestamp.h"
 
 /* User-settable GUC parameters */
-int			vacuum_defer_cleanup_age;
+int64		vacuum_defer_cleanup_age;
 int			max_standby_archive_delay = 30 * 1000;
 int			max_standby_streaming_delay = 30 * 1000;
 bool		log_recovery_conflict_waits = false;
@@ -486,8 +486,8 @@ ResolveRecoveryConflictWithSnapshotFullXid(FullTransactionId latestRemovedFullXi
 	FullTransactionId nextXid = ReadNextFullTransactionId();
 	uint64		diff;
 
-	diff = U64FromFullTransactionId(nextXid) -
-		U64FromFullTransactionId(latestRemovedFullXid);
+	diff = XidFromFullTransactionId(nextXid) -
+		XidFromFullTransactionId(latestRemovedFullXid);
 	if (diff < MaxTransactionId / 2)
 	{
 		TransactionId latestRemovedXid;
diff --git a/src/backend/storage/lmgr/lmgr.c b/src/backend/storage/lmgr/lmgr.c
index 1543da6162..c7b2179360 100644
--- a/src/backend/storage/lmgr/lmgr.c
+++ b/src/backend/storage/lmgr/lmgr.c
@@ -1163,10 +1163,18 @@ DescribeLockTag(StringInfo buf, const LOCKTAG *tag)
 							 tag->locktag_field1);
 			break;
 		case LOCKTAG_TRANSACTION:
-			appendStringInfo(buf,
-							 _("transaction %u"),
-							 tag->locktag_field1);
-			break;
+			{
+				char		xid_str[32];
+
+				/* make translatable string */
+				snprintf(xid_str, sizeof(xid_str), "%llu",
+						 (unsigned long long)
+						 (TransactionId) tag->locktag_field1 |
+						 ((TransactionId) tag->locktag_field2 << 32));
+
+				appendStringInfo(buf, _("transaction %s"), xid_str);
+				break;
+			}
 		case LOCKTAG_VIRTUALTRANSACTION:
 			appendStringInfo(buf,
 							 _("virtual transaction %d/%u"),
diff --git a/src/backend/storage/lmgr/lock.c b/src/backend/storage/lmgr/lock.c
index 5f5803f681..02e1bae99b 100644
--- a/src/backend/storage/lmgr/lock.c
+++ b/src/backend/storage/lmgr/lock.c
@@ -4060,7 +4060,7 @@ GetRunningTransactionLocks(int *nlocks)
 		{
 			PGPROC	   *proc = proclock->tag.myProc;
 			LOCK	   *lock = proclock->tag.myLock;
-			TransactionId xid = proc->xid;
+			TransactionId xid = pg_atomic_read_u64(&proc->xid);
 
 			/*
 			 * Don't record locks for transactions if we know they have
@@ -4689,7 +4689,7 @@ VirtualXactLock(VirtualTransactionId vxid, bool wait)
 	 * so we won't save an XID of a different VXID.  It doesn't matter whether
 	 * we save this before or after setting up the primary lock table entry.
 	 */
-	xid = proc->xid;
+	xid = pg_atomic_read_u64(&proc->xid);
 
 	/* Done with proc->fpLockBits */
 	LWLockRelease(&proc->fpInfoLock);
diff --git a/src/backend/storage/lmgr/predicate.c b/src/backend/storage/lmgr/predicate.c
index 539dffc311..71df25f1bc 100644
--- a/src/backend/storage/lmgr/predicate.c
+++ b/src/backend/storage/lmgr/predicate.c
@@ -333,9 +333,9 @@ static SlruCtlData SerialSlruCtlData;
 
 #define SerialValue(slotno, xid) (*((SerCommitSeqNo *) \
 	(SerialSlruCtl->shared->page_buffer[slotno] + \
-	((((uint32) (xid)) % SERIAL_ENTRIESPERPAGE) * SERIAL_ENTRYSIZE))))
+	((((uint64) (xid)) % SERIAL_ENTRIESPERPAGE) * SERIAL_ENTRYSIZE))))
 
-#define SerialPage(xid)	(((uint32) (xid)) / SERIAL_ENTRIESPERPAGE)
+#define SerialPage(xid)		((int64) (((uint64) (xid)) / SERIAL_ENTRIESPERPAGE))
 
 typedef struct SerialControlData
 {
diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c
index 37aaab1338..e3545ff8c4 100644
--- a/src/backend/storage/lmgr/proc.c
+++ b/src/backend/storage/lmgr/proc.c
@@ -205,7 +205,7 @@ InitProcGlobal(void)
 	 * how hotly they are accessed.
 	 */
 	ProcGlobal->xids =
-		(TransactionId *) ShmemAlloc(TotalProcs * sizeof(*ProcGlobal->xids));
+		(pg_atomic_uint64 *) ShmemAlloc(TotalProcs * sizeof(*ProcGlobal->xids));
 	MemSet(ProcGlobal->xids, 0, TotalProcs * sizeof(*ProcGlobal->xids));
 	ProcGlobal->subxidStates = (XidCacheStatus *) ShmemAlloc(TotalProcs * sizeof(*ProcGlobal->subxidStates));
 	MemSet(ProcGlobal->subxidStates, 0, TotalProcs * sizeof(*ProcGlobal->subxidStates));
@@ -214,6 +214,7 @@ InitProcGlobal(void)
 
 	for (i = 0; i < TotalProcs; i++)
 	{
+		pg_atomic_init_u64(&ProcGlobal->xids[i], 0);
 		/* Common initialization for all PGPROCs, regardless of type. */
 
 		/*
@@ -383,8 +384,8 @@ InitProcess(void)
 	MyProc->lxid = InvalidLocalTransactionId;
 	MyProc->fpVXIDLock = false;
 	MyProc->fpLocalTransactionId = InvalidLocalTransactionId;
-	MyProc->xid = InvalidTransactionId;
-	MyProc->xmin = InvalidTransactionId;
+	pg_atomic_init_u64(&MyProc->xid, InvalidTransactionId);
+	pg_atomic_init_u64(&MyProc->xmin, InvalidTransactionId);
 	MyProc->pid = MyProcPid;
 	/* backendId, databaseId and roleId will be filled in later */
 	MyProc->backendId = InvalidBackendId;
@@ -570,8 +571,8 @@ InitAuxiliaryProcess(void)
 	MyProc->lxid = InvalidLocalTransactionId;
 	MyProc->fpVXIDLock = false;
 	MyProc->fpLocalTransactionId = InvalidLocalTransactionId;
-	MyProc->xid = InvalidTransactionId;
-	MyProc->xmin = InvalidTransactionId;
+	pg_atomic_init_u64(&MyProc->xid, InvalidTransactionId);
+	pg_atomic_init_u64(&MyProc->xmin, InvalidTransactionId);
 	MyProc->backendId = InvalidBackendId;
 	MyProc->databaseId = InvalidOid;
 	MyProc->roleId = InvalidOid;
diff --git a/src/backend/storage/page/bufpage.c b/src/backend/storage/page/bufpage.c
index a3d367db51..fdca863056 100644
--- a/src/backend/storage/page/bufpage.c
+++ b/src/backend/storage/page/bufpage.c
@@ -21,11 +21,31 @@
 #include "storage/checksum.h"
 #include "utils/memdebug.h"
 #include "utils/memutils.h"
+#include "utils/snapmgr.h"
 
 
 /* GUC variable */
 bool		ignore_checksum_failure = false;
 
+/*
+ * HeapPageSpecialData used when pd_special == BLCKSZ.  This is special format
+ * used when page with 32-bit xids doesn't fit HeapPageSpecialData.  Then
+ * all xmin's are frozen (can do this for all live tuples after pg_upgrade),
+ * while 64-bit xmax is stored in both t_heap.t_xmin and t_heap.t_xmax.
+ * This is so-called "double xmax" format.
+ */
+static HeapPageSpecialData heapDoubleXmaxSpecialData =
+{
+	.pd_xid_base = MaxTransactionId,
+	.pd_multi_base = MaxTransactionId
+};
+HeapPageSpecial heapDoubleXmaxSpecial = &heapDoubleXmaxSpecialData;
+
+static ToastPageSpecialData toastDoubleXmaxSpecialData =
+{
+	.pd_xid_base = MaxTransactionId
+};
+ToastPageSpecial toastDoubleXmaxSpecial = &toastDoubleXmaxSpecialData;
 
 /* ----------------------------------------------------------------
  *						Page support functions
@@ -432,15 +452,144 @@ PageRestoreTempPage(Page tempPage, Page oldPage)
 }
 
 /*
- * Tuple defrag support for PageRepairFragmentation and PageIndexMultiDelete
+ * Get minimum and maximum values of xid and multixact on "double xmax" page.
  */
-typedef struct itemIdCompactData
+static void
+heap_page_double_xmax_get_min_max(Page page,
+								  TransactionId *xid_min,
+								  TransactionId *xid_max,
+								  MultiXactId *multi_min,
+								  MultiXactId *multi_max)
 {
-	uint16		offsetindex;	/* linp array index */
-	int16		itemoff;		/* page offset of item data */
-	uint16		alignedlen;		/* MAXALIGN(item data len) */
-} itemIdCompactData;
-typedef itemIdCompactData *itemIdCompact;
+	bool		xid_found = false,
+				multi_found = false;
+	OffsetNumber offnum,
+				maxoff;
+
+	maxoff = PageGetMaxOffsetNumber(page);
+
+	for (offnum = FirstOffsetNumber;
+		 offnum <= maxoff;
+		 offnum = OffsetNumberNext(offnum))
+	{
+		ItemId		itemid;
+		HeapTupleHeader htup;
+		TransactionId xmax;
+
+		itemid = PageGetItemId(page, offnum);
+
+		if (!ItemIdIsNormal(itemid))
+			continue;
+
+		htup = (HeapTupleHeader) PageGetItem(page, itemid);
+
+		xmax = HeapTupleHeaderGetDoubleXmax(htup);
+
+		if (!TransactionIdIsNormal(xmax))
+			continue;
+
+		if (!(htup->t_infomask & HEAP_XMAX_IS_MULTI))
+		{
+			if (!xid_found)
+			{
+				*xid_min = *xid_max = xmax;
+				xid_found = true;
+			}
+			else
+			{
+				*xid_min = Min(*xid_min, xmax);
+				*xid_max = Max(*xid_max, xmax);
+			}
+		}
+		else
+		{
+			if (!multi_found)
+			{
+				*multi_min = *multi_max = xmax;
+				multi_found = true;
+			}
+			else
+			{
+				*multi_min = Min(*multi_min, xmax);
+				*multi_max = Max(*multi_max, xmax);
+			}
+		}
+	}
+}
+
+/*
+ * Add special area to heap page, so convert from "double xmax" to normal
+ * format.
+ */
+static void
+heap_page_add_special_area(ItemIdCompact itemidbase, int nitems, Page page,
+						   TransactionId xid_base, MultiXactId multi_base,
+						   bool is_toast)
+{
+	char		newPage[BLCKSZ];
+	PageHeader	phdr = (PageHeader) page;
+	PageHeader	new_phdr = (PageHeader) newPage;
+	Offset		upper;
+	int			i;
+
+	memcpy(newPage, page, phdr->pd_lower);
+
+	/* Add special area */
+	if (is_toast)
+	{
+		ToastPageSpecial special;
+
+		new_phdr->pd_special = PageGetPageSize(newPage) - sizeof(ToastPageSpecialData);
+		special = (ToastPageSpecial) ((Pointer) (newPage) + new_phdr->pd_special);
+		special->pd_xid_base = xid_base;
+	}
+	else
+	{
+		HeapPageSpecial special;
+
+		new_phdr->pd_special = PageGetPageSize(newPage) - sizeof(HeapPageSpecialData);
+		special = (HeapPageSpecial) ((Pointer) (newPage) + new_phdr->pd_special);
+		special->pd_xid_base = xid_base;
+		special->pd_multi_base = multi_base;
+	}
+
+	/* sort itemIdSortData array into decreasing itemoff order */
+	qsort((char *) itemidbase, nitems, sizeof(ItemIdCompactData),
+		  itemoffcompare);
+
+	upper = new_phdr->pd_special;
+	for (i = 0; i < nitems; i++)
+	{
+		ItemIdCompact itemidptr = &itemidbase[i];
+		ItemId		lp;
+		HeapTupleHeader old_htup;
+		HeapTupleHeader new_htup;
+		TransactionId xmax;
+
+		lp = PageGetItemId(page, itemidptr->offsetindex + 1);
+		old_htup = (HeapTupleHeader) PageGetItem(page, lp);
+		upper -= itemidptr->alignedlen;
+		memcpy((Pointer) newPage + upper,
+			   (Pointer) page + itemidptr->itemoff,
+			   itemidptr->alignedlen);
+		lp = PageGetItemId(newPage, itemidptr->offsetindex + 1);
+		lp->lp_off = upper;
+		new_htup = (HeapTupleHeader) PageGetItem(newPage, lp);
+
+		/* Convert xmax value */
+		new_htup->t_choice.t_heap.t_xmin = FrozenTransactionId;
+		xmax = HeapTupleHeaderGetDoubleXmax(old_htup);
+		if (!(new_htup->t_infomask & HEAP_XMAX_IS_MULTI))
+			new_htup->t_choice.t_heap.t_xmax = NormalTransactionIdToShort(xid_base, xmax);
+		else
+			new_htup->t_choice.t_heap.t_xmax = NormalTransactionIdToShort(multi_base, xmax);
+	}
+
+	new_phdr->pd_upper = upper;
+
+	memcpy(page, newPage, PageGetPageSize(newPage));
+	elog(DEBUG2, "convert heap page from double xmax to normal format");
+}
 
 /*
  * After removing or marking some line pointers unused, move the tuples to
@@ -471,21 +620,47 @@ typedef itemIdCompactData *itemIdCompact;
  * Callers must ensure that nitems is > 0
  */
 static void
-compactify_tuples(itemIdCompact itemidbase, int nitems, Page page, bool presorted)
+compactify_tuples(ItemIdCompact itemidbase, int nitems, Page page,
+				  bool presorted, bool addspecial, bool is_toast)
 {
 	PageHeader	phdr = (PageHeader) page;
 	Offset		upper;
 	Offset		copy_tail;
 	Offset		copy_head;
-	itemIdCompact itemidptr;
+	ItemIdCompact itemidptr;
 	int			i;
 
 	/* Code within will not work correctly if nitems == 0 */
 	Assert(nitems > 0);
 
-	if (presorted)
+	/* Add special area to the heap page if possible */
+	if (addspecial)
 	{
+		TransactionId xid_min = FirstNormalTransactionId,
+					xid_max = FirstNormalTransactionId;
+		MultiXactId multi_min = FirstNormalTransactionId,
+					multi_max = FirstNormalTransactionId;
 
+		Assert(phdr->pd_special == PageGetPageSize(page));
+
+		heap_page_double_xmax_get_min_max(page, &xid_min, &xid_max,
+										  &multi_min, &multi_max);
+
+		if (xid_max - xid_min < (TransactionId) (MaxShortTransactionId - FirstNormalTransactionId) &&
+			multi_max - multi_min < (TransactionId) (MaxShortTransactionId - FirstNormalTransactionId))
+		{
+			Assert(xid_min >= FirstNormalTransactionId);
+			Assert(multi_min >= FirstNormalTransactionId);
+			heap_page_add_special_area(itemidbase, nitems, page,
+									   xid_min - FirstNormalTransactionId,
+									   multi_min - FirstNormalTransactionId,
+									   is_toast);
+			return;
+		}
+	}
+
+	if (presorted)
+	{
 #ifdef USE_ASSERT_CHECKING
 		{
 			/*
@@ -696,14 +871,14 @@ compactify_tuples(itemIdCompact itemidbase, int nitems, Page page, bool presorte
  * the line pointer array following array truncation.
  */
 void
-PageRepairFragmentation(Page page)
+PageRepairFragmentation(Page page, bool is_toast)
 {
 	Offset		pd_lower = ((PageHeader) page)->pd_lower;
 	Offset		pd_upper = ((PageHeader) page)->pd_upper;
 	Offset		pd_special = ((PageHeader) page)->pd_special;
 	Offset		last_offset;
-	itemIdCompactData itemidbase[MaxHeapTuplesPerPage];
-	itemIdCompact itemidptr;
+	ItemIdCompactData itemidbase[MaxHeapTuplesPerPage];
+	ItemIdCompact itemidptr;
 	ItemId		lp;
 	int			nline,
 				nstorage,
@@ -777,11 +952,30 @@ PageRepairFragmentation(Page page)
 	nstorage = itemidptr - itemidbase;
 	if (nstorage == 0)
 	{
+		if (pd_special == PageGetPageSize(page))
+		{
+			if (is_toast)
+			{
+				pd_special = PageGetPageSize(page) - sizeof(ToastPageSpecialData);
+				((PageHeader) page)->pd_special = pd_special;
+				ToastPageGetSpecial(page)->pd_xid_base = 0;
+			}
+			else
+			{
+				pd_special = PageGetPageSize(page) - sizeof(HeapPageSpecialData);
+				((PageHeader) page)->pd_special = pd_special;
+				HeapPageGetSpecial(page)->pd_xid_base = 0;
+				HeapPageGetSpecial(page)->pd_multi_base = 0;
+			}
+		}
+
 		/* Page is completely empty, so just reset it quickly */
 		((PageHeader) page)->pd_upper = pd_special;
 	}
 	else
 	{
+		bool		addspecial = false;
+
 		/* Need to compact the page the hard way */
 		if (totallen > (Size) (pd_special - pd_lower))
 			ereport(ERROR,
@@ -789,7 +983,25 @@ PageRepairFragmentation(Page page)
 					 errmsg("corrupted item lengths: total %u, available space %u",
 							(unsigned int) totallen, pd_special - pd_lower)));
 
-		compactify_tuples(itemidbase, nstorage, page, presorted);
+		/*
+		 * Try to add special area to the heap page if it has enough of free
+		 * space.
+		 */
+		if (pd_special == PageGetPageSize(page))
+		{
+			Size	special_size,
+					actual_size;
+
+			special_size = is_toast ? sizeof(ToastPageSpecialData) :
+									  sizeof(HeapPageSpecialData);
+			actual_size = (Size) (pd_special - pd_lower) - totallen;
+
+			if (actual_size >= special_size)
+				addspecial = true;
+		}
+
+		compactify_tuples(itemidbase, nstorage, page, presorted, addspecial,
+						  is_toast);
 	}
 
 	if (finalusedlp != nline)
@@ -992,6 +1204,9 @@ PageGetHeapFreeSpace(Page page)
 {
 	Size		space;
 
+	if (HeapPageIsDoubleXmax(page))
+		return 0;
+
 	space = PageGetFreeSpace(page);
 	if (space > 0)
 	{
@@ -1165,9 +1380,9 @@ PageIndexMultiDelete(Page page, OffsetNumber *itemnos, int nitems)
 	Offset		pd_upper = phdr->pd_upper;
 	Offset		pd_special = phdr->pd_special;
 	Offset		last_offset;
-	itemIdCompactData itemidbase[MaxIndexTuplesPerPage];
+	ItemIdCompactData itemidbase[MaxIndexTuplesPerPage];
 	ItemIdData	newitemids[MaxIndexTuplesPerPage];
-	itemIdCompact itemidptr;
+	ItemIdCompact itemidptr;
 	ItemId		lp;
 	int			nline,
 				nused;
@@ -1275,7 +1490,12 @@ PageIndexMultiDelete(Page page, OffsetNumber *itemnos, int nitems)
 
 	/* and compactify the tuple data */
 	if (nused > 0)
-		compactify_tuples(itemidbase, nused, page, presorted);
+	{
+		bool	is_toast;
+
+		is_toast = BLCKSZ - pd_special == sizeof(ToastPageSpecialData);
+		compactify_tuples(itemidbase, nused, page, presorted, false, is_toast);
+	}
 	else
 		phdr->pd_upper = pd_special;
 }
diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index 4bf0cdee1d..d1cdfbae8a 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3738,15 +3738,13 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx,
 
 			case 'm':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_mxid = value;
+					start_mxid = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_mxid) /* overflow */
+						!StartMultiXactIdIsValid(start_mxid))
 					{
 						ereport(ERROR,
 								(errcode(ERRCODE_SYNTAX_ERROR),
@@ -3769,15 +3767,13 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx,
 
 			case 'o':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_mxoff = value;
+					start_mxoff = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_mxoff) /* overflow */
+						!StartMultiXactOffsetIsValid(start_mxoff))
 					{
 						ereport(ERROR,
 								(errcode(ERRCODE_SYNTAX_ERROR),
@@ -3842,15 +3838,13 @@ process_postgres_switches(int argc, char *argv[], GucContext ctx,
 
 			case 'x':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_xid = value;
+					start_xid = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_xid) /* overflow */
+						!StartTransactionIdIsValid(start_xid))
 					{
 						ereport(ERROR,
 								(errcode(ERRCODE_SYNTAX_ERROR),
@@ -4014,7 +4008,6 @@ PostgresSingleUserMain(int argc, char *argv[],
 	PostgresMain(dbname, username);
 }
 
-
 /* ----------------------------------------------------------------
  * PostgresMain
  *	   postgres main loop -- all backends, interactive or otherwise loop here
diff --git a/src/backend/utils/adt/enum.c b/src/backend/utils/adt/enum.c
index 0cc7a6d8ad..04ca6ff16e 100644
--- a/src/backend/utils/adt/enum.c
+++ b/src/backend/utils/adt/enum.c
@@ -76,7 +76,7 @@ check_safe_enum_use(HeapTuple enumval_tup)
 	 * Usually, a row would get hinted as committed when it's read or loaded
 	 * into syscache; but just in case not, let's check the xmin directly.
 	 */
-	xmin = HeapTupleHeaderGetXmin(enumval_tup->t_data);
+	xmin = HeapTupleGetXmin(enumval_tup);
 	if (!TransactionIdIsInProgress(xmin) &&
 		TransactionIdDidCommit(xmin))
 		return;
diff --git a/src/backend/utils/adt/jsonfuncs.c b/src/backend/utils/adt/jsonfuncs.c
index 9819e1a45c..0b72e23a34 100644
--- a/src/backend/utils/adt/jsonfuncs.c
+++ b/src/backend/utils/adt/jsonfuncs.c
@@ -3706,6 +3706,7 @@ populate_recordset_record(PopulateRecordsetState *state, JsObject *obj)
 	tuple.t_len = HeapTupleHeaderGetDatumLength(tuphead);
 	ItemPointerSetInvalid(&(tuple.t_self));
 	tuple.t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(&tuple);
 	tuple.t_data = tuphead;
 
 	tuplestore_puttuple(state->tuple_store, &tuple);
diff --git a/src/backend/utils/adt/lockfuncs.c b/src/backend/utils/adt/lockfuncs.c
index 5b54863c81..9e2e03caef 100644
--- a/src/backend/utils/adt/lockfuncs.c
+++ b/src/backend/utils/adt/lockfuncs.c
@@ -77,7 +77,7 @@ VXIDGetDatum(BackendId bid, LocalTransactionId lxid)
 	 * The representation is "<bid>/<lxid>", decimal and unsigned decimal
 	 * respectively.  Note that elog.c also knows how to format a vxid.
 	 */
-	char		vxidstr[32];
+	char		vxidstr[64];
 
 	snprintf(vxidstr, sizeof(vxidstr), "%d/%llu", bid,
 			 (unsigned long long) lxid);
@@ -293,7 +293,9 @@ pg_lock_status(PG_FUNCTION_ARGS)
 				break;
 			case LOCKTAG_TRANSACTION:
 				values[6] =
-					TransactionIdGetDatum(instance->locktag.locktag_field1);
+					TransactionIdGetDatum(
+										  (TransactionId) instance->locktag.locktag_field1 |
+										  ((TransactionId) instance->locktag.locktag_field2 << 32));
 				nulls[1] = true;
 				nulls[2] = true;
 				nulls[3] = true;
@@ -305,7 +307,8 @@ pg_lock_status(PG_FUNCTION_ARGS)
 				break;
 			case LOCKTAG_VIRTUALTRANSACTION:
 				values[5] = VXIDGetDatum(instance->locktag.locktag_field1,
-										 instance->locktag.locktag_field2);
+										 (TransactionId) instance->locktag.locktag_field2 |
+										 ((TransactionId) instance->locktag.locktag_field3 << 32));
 				nulls[1] = true;
 				nulls[2] = true;
 				nulls[3] = true;
diff --git a/src/backend/utils/adt/pgstatfuncs.c b/src/backend/utils/adt/pgstatfuncs.c
index 893690dad5..41366cc87c 100644
--- a/src/backend/utils/adt/pgstatfuncs.c
+++ b/src/backend/utils/adt/pgstatfuncs.c
@@ -15,6 +15,7 @@
 #include "postgres.h"
 
 #include "access/htup_details.h"
+#include "access/xact.h"
 #include "access/xlog.h"
 #include "access/xlogprefetcher.h"
 #include "catalog/pg_authid.h"
diff --git a/src/backend/utils/adt/rowtypes.c b/src/backend/utils/adt/rowtypes.c
index db843a0fbf..5e08d02d64 100644
--- a/src/backend/utils/adt/rowtypes.c
+++ b/src/backend/utils/adt/rowtypes.c
@@ -327,6 +327,7 @@ record_out(PG_FUNCTION_ARGS)
 	tuple.t_len = HeapTupleHeaderGetDatumLength(rec);
 	ItemPointerSetInvalid(&(tuple.t_self));
 	tuple.t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(&tuple);
 	tuple.t_data = rec;
 
 	/*
@@ -694,6 +695,7 @@ record_send(PG_FUNCTION_ARGS)
 	tuple.t_len = HeapTupleHeaderGetDatumLength(rec);
 	ItemPointerSetInvalid(&(tuple.t_self));
 	tuple.t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(&tuple);
 	tuple.t_data = rec;
 
 	/*
@@ -844,10 +846,12 @@ record_cmp(FunctionCallInfo fcinfo)
 	tuple1.t_len = HeapTupleHeaderGetDatumLength(record1);
 	ItemPointerSetInvalid(&(tuple1.t_self));
 	tuple1.t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(&tuple1);
 	tuple1.t_data = record1;
 	tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
 	ItemPointerSetInvalid(&(tuple2.t_self));
 	tuple2.t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(&tuple2);
 	tuple2.t_data = record2;
 
 	/*
@@ -1089,10 +1093,12 @@ record_eq(PG_FUNCTION_ARGS)
 	ItemPointerSetInvalid(&(tuple1.t_self));
 	tuple1.t_tableOid = InvalidOid;
 	tuple1.t_data = record1;
+	HeapTupleSetZeroBase(&tuple1);
 	tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
 	ItemPointerSetInvalid(&(tuple2.t_self));
 	tuple2.t_tableOid = InvalidOid;
 	tuple2.t_data = record2;
+	HeapTupleSetZeroBase(&tuple2);
 
 	/*
 	 * We arrange to look up the needed comparison info just once per series
@@ -1351,10 +1357,12 @@ record_image_cmp(FunctionCallInfo fcinfo)
 	ItemPointerSetInvalid(&(tuple1.t_self));
 	tuple1.t_tableOid = InvalidOid;
 	tuple1.t_data = record1;
+	HeapTupleSetZeroBase(&tuple1);
 	tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
 	ItemPointerSetInvalid(&(tuple2.t_self));
 	tuple2.t_tableOid = InvalidOid;
 	tuple2.t_data = record2;
+	HeapTupleSetZeroBase(&tuple2);
 
 	/*
 	 * We arrange to look up the needed comparison info just once per series
@@ -1597,10 +1605,12 @@ record_image_eq(PG_FUNCTION_ARGS)
 	ItemPointerSetInvalid(&(tuple1.t_self));
 	tuple1.t_tableOid = InvalidOid;
 	tuple1.t_data = record1;
+	HeapTupleSetZeroBase(&tuple1);
 	tuple2.t_len = HeapTupleHeaderGetDatumLength(record2);
 	ItemPointerSetInvalid(&(tuple2.t_self));
 	tuple2.t_tableOid = InvalidOid;
 	tuple2.t_data = record2;
+	HeapTupleSetZeroBase(&tuple2);
 
 	/*
 	 * We arrange to look up the needed comparison info just once per series
@@ -1800,6 +1810,7 @@ hash_record(PG_FUNCTION_ARGS)
 	ItemPointerSetInvalid(&(tuple.t_self));
 	tuple.t_tableOid = InvalidOid;
 	tuple.t_data = record;
+	HeapTupleSetZeroBase(&tuple);
 
 	/*
 	 * We arrange to look up the needed hashing info just once per series of
@@ -1921,6 +1932,7 @@ hash_record_extended(PG_FUNCTION_ARGS)
 	ItemPointerSetInvalid(&(tuple.t_self));
 	tuple.t_tableOid = InvalidOid;
 	tuple.t_data = record;
+	HeapTupleSetZeroBase(&tuple);
 
 	/*
 	 * We arrange to look up the needed hashing info just once per series of
diff --git a/src/backend/utils/adt/xid.c b/src/backend/utils/adt/xid.c
index e4b4952a28..056752cfaf 100644
--- a/src/backend/utils/adt/xid.c
+++ b/src/backend/utils/adt/xid.c
@@ -32,16 +32,16 @@ xidin(PG_FUNCTION_ARGS)
 {
 	char	   *str = PG_GETARG_CSTRING(0);
 
-	PG_RETURN_TRANSACTIONID((TransactionId) strtoul(str, NULL, 0));
+	PG_RETURN_TRANSACTIONID((TransactionId) strtou64(str, NULL, 0));
 }
 
 Datum
 xidout(PG_FUNCTION_ARGS)
 {
 	TransactionId transactionId = PG_GETARG_TRANSACTIONID(0);
-	char	   *result = (char *) palloc(16);
+	char	   *result = (char *) palloc(32);
 
-	snprintf(result, 16, "%lu", (unsigned long) transactionId);
+	snprintf(result, 32, "%llu", (unsigned long long) transactionId);
 	PG_RETURN_CSTRING(result);
 }
 
@@ -52,8 +52,13 @@ Datum
 xidrecv(PG_FUNCTION_ARGS)
 {
 	StringInfo	buf = (StringInfo) PG_GETARG_POINTER(0);
+	uint32		lo,
+				hi;
+
+	lo = (uint32) pq_getmsgint(buf, sizeof(TransactionId));
+	hi = (uint32) pq_getmsgint(buf, sizeof(TransactionId));
 
-	PG_RETURN_TRANSACTIONID((TransactionId) pq_getmsgint(buf, sizeof(TransactionId)));
+	PG_RETURN_TRANSACTIONID((uint64) lo + ((uint64) hi << 32));
 }
 
 /*
@@ -64,9 +69,15 @@ xidsend(PG_FUNCTION_ARGS)
 {
 	TransactionId arg1 = PG_GETARG_TRANSACTIONID(0);
 	StringInfoData buf;
+	uint32		lo,
+				hi;
+
+	lo = (uint32) (arg1 & 0xFFFFFFFF);
+	hi = (uint32) (arg1 >> 32);
 
 	pq_begintypsend(&buf);
-	pq_sendint32(&buf, arg1);
+	pq_sendint(&buf, lo, sizeof(lo));
+	pq_sendint(&buf, hi, sizeof(hi));
 	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
 }
 
@@ -105,9 +116,9 @@ xid_age(PG_FUNCTION_ARGS)
 
 	/* Permanent XIDs are always infinitely old */
 	if (!TransactionIdIsNormal(xid))
-		PG_RETURN_INT32(INT_MAX);
+		PG_RETURN_INT64(PG_INT8_MAX);
 
-	PG_RETURN_INT32((int32) (now - xid));
+	PG_RETURN_INT64((int64) (now - xid));
 }
 
 /*
@@ -120,9 +131,9 @@ mxid_age(PG_FUNCTION_ARGS)
 	MultiXactId now = ReadNextMultiXactId();
 
 	if (!MultiXactIdIsValid(xid))
-		PG_RETURN_INT32(INT_MAX);
+		PG_RETURN_INT64(PG_INT8_MAX);
 
-	PG_RETURN_INT32((int32) (now - xid));
+	PG_RETURN_INT64((int64) (now - xid));
 }
 
 /*
@@ -184,7 +195,7 @@ xid8in(PG_FUNCTION_ARGS)
 {
 	char	   *str = PG_GETARG_CSTRING(0);
 
-	PG_RETURN_FULLTRANSACTIONID(FullTransactionIdFromU64(strtou64(str, NULL, 0)));
+	PG_RETURN_FULLTRANSACTIONID(FullTransactionIdFromXid(strtou64(str, NULL, 0)));
 }
 
 Datum
@@ -193,7 +204,7 @@ xid8out(PG_FUNCTION_ARGS)
 	FullTransactionId fxid = PG_GETARG_FULLTRANSACTIONID(0);
 	char	   *result = (char *) palloc(21);
 
-	snprintf(result, 21, UINT64_FORMAT, U64FromFullTransactionId(fxid));
+	snprintf(result, 21, UINT64_FORMAT, XidFromFullTransactionId(fxid));
 	PG_RETURN_CSTRING(result);
 }
 
@@ -204,7 +215,7 @@ xid8recv(PG_FUNCTION_ARGS)
 	uint64		value;
 
 	value = (uint64) pq_getmsgint64(buf);
-	PG_RETURN_FULLTRANSACTIONID(FullTransactionIdFromU64(value));
+	PG_RETURN_FULLTRANSACTIONID(FullTransactionIdFromXid(value));
 }
 
 Datum
@@ -214,7 +225,7 @@ xid8send(PG_FUNCTION_ARGS)
 	StringInfoData buf;
 
 	pq_begintypsend(&buf);
-	pq_sendint64(&buf, (uint64) U64FromFullTransactionId(arg1));
+	pq_sendint64(&buf, (uint64) XidFromFullTransactionId(arg1));
 	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
 }
 
diff --git a/src/backend/utils/adt/xid8funcs.c b/src/backend/utils/adt/xid8funcs.c
index d8e40b3b96..6257d985d6 100644
--- a/src/backend/utils/adt/xid8funcs.c
+++ b/src/backend/utils/adt/xid8funcs.c
@@ -80,8 +80,7 @@ typedef struct
  * It is an ERROR if the xid is in the future.  Otherwise, returns true if
  * the transaction is still new enough that we can determine whether it
  * committed and false otherwise.  If *extracted_xid is not NULL, it is set
- * to the low 32 bits of the transaction ID (i.e. the actual XID, without the
- * epoch).
+ * to the actual transaction ID.
  *
  * The caller must hold XactTruncationLock since it's dealing with arbitrary
  * XIDs, and must continue to hold it until it's done with any clog lookups
@@ -90,15 +89,10 @@ typedef struct
 static bool
 TransactionIdInRecentPast(FullTransactionId fxid, TransactionId *extracted_xid)
 {
-	uint32		xid_epoch = EpochFromFullTransactionId(fxid);
 	TransactionId xid = XidFromFullTransactionId(fxid);
-	uint32		now_epoch;
-	TransactionId now_epoch_next_xid;
 	FullTransactionId now_fullxid;
 
 	now_fullxid = ReadNextFullTransactionId();
-	now_epoch_next_xid = XidFromFullTransactionId(now_fullxid);
-	now_epoch = EpochFromFullTransactionId(now_fullxid);
 
 	if (extracted_xid != NULL)
 		*extracted_xid = xid;
@@ -115,7 +109,7 @@ TransactionIdInRecentPast(FullTransactionId fxid, TransactionId *extracted_xid)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("transaction ID %llu is in the future",
-						(unsigned long long) U64FromFullTransactionId(fxid))));
+						(unsigned long long) XidFromFullTransactionId(fxid))));
 
 	/*
 	 * ShmemVariableCache->oldestClogXid is protected by XactTruncationLock,
@@ -127,48 +121,15 @@ TransactionIdInRecentPast(FullTransactionId fxid, TransactionId *extracted_xid)
 	Assert(LWLockHeldByMe(XactTruncationLock));
 
 	/*
-	 * If the transaction ID has wrapped around, it's definitely too old to
-	 * determine the commit status.  Otherwise, we can compare it to
-	 * ShmemVariableCache->oldestClogXid to determine whether the relevant
-	 * CLOG entry is guaranteed to still exist.
+	 * We compare xid to ShmemVariableCache->oldestClogXid to determine
+	 * whether the relevant CLOG entry is guaranteed to still exist.
 	 */
-	if (xid_epoch + 1 < now_epoch
-		|| (xid_epoch + 1 == now_epoch && xid < now_epoch_next_xid)
-		|| TransactionIdPrecedes(xid, ShmemVariableCache->oldestClogXid))
+	if (TransactionIdPrecedes(xid, ShmemVariableCache->oldestClogXid))
 		return false;
 
 	return true;
 }
 
-/*
- * Convert a TransactionId obtained from a snapshot held by the caller to a
- * FullTransactionId.  Use next_fxid as a reference FullTransactionId, so that
- * we can compute the high order bits.  It must have been obtained by the
- * caller with ReadNextFullTransactionId() after the snapshot was created.
- */
-static FullTransactionId
-widen_snapshot_xid(TransactionId xid, FullTransactionId next_fxid)
-{
-	TransactionId next_xid = XidFromFullTransactionId(next_fxid);
-	uint32		epoch = EpochFromFullTransactionId(next_fxid);
-
-	/* Special transaction ID. */
-	if (!TransactionIdIsNormal(xid))
-		return FullTransactionIdFromEpochAndXid(0, xid);
-
-	/*
-	 * The 64 bit result must be <= next_fxid, since next_fxid hadn't been
-	 * issued yet when the snapshot was created.  Every TransactionId in the
-	 * snapshot must therefore be from the same epoch as next_fxid, or the
-	 * epoch before.  We know this because next_fxid is never allow to get
-	 * more than one epoch ahead of the TransactionIds in any snapshot.
-	 */
-	if (xid > next_xid)
-		epoch--;
-
-	return FullTransactionIdFromEpochAndXid(epoch, xid);
-}
-
 /*
  * txid comparator for qsort/bsearch
  */
@@ -295,12 +256,12 @@ parse_snapshot(const char *str)
 	char	   *endp;
 	StringInfo	buf;
 
-	xmin = FullTransactionIdFromU64(strtou64(str, &endp, 10));
+	xmin = FullTransactionIdFromXid(strtou64(str, &endp, 10));
 	if (*endp != ':')
 		goto bad_format;
 	str = endp + 1;
 
-	xmax = FullTransactionIdFromU64(strtou64(str, &endp, 10));
+	xmax = FullTransactionIdFromXid(strtou64(str, &endp, 10));
 	if (*endp != ':')
 		goto bad_format;
 	str = endp + 1;
@@ -318,7 +279,7 @@ parse_snapshot(const char *str)
 	while (*str != '\0')
 	{
 		/* read next value */
-		val = FullTransactionIdFromU64(strtou64(str, &endp, 10));
+		val = FullTransactionIdFromXid(strtou64(str, &endp, 10));
 		str = endp;
 
 		/* require the input to be in order */
@@ -397,7 +358,6 @@ pg_current_snapshot(PG_FUNCTION_ARGS)
 	uint32		nxip,
 				i;
 	Snapshot	cur;
-	FullTransactionId next_fxid = ReadNextFullTransactionId();
 
 	cur = GetActiveSnapshot();
 	if (cur == NULL)
@@ -415,11 +375,11 @@ pg_current_snapshot(PG_FUNCTION_ARGS)
 	snap = palloc(PG_SNAPSHOT_SIZE(nxip));
 
 	/* fill */
-	snap->xmin = widen_snapshot_xid(cur->xmin, next_fxid);
-	snap->xmax = widen_snapshot_xid(cur->xmax, next_fxid);
+	snap->xmin = FullTransactionIdFromXid(cur->xmin);
+	snap->xmax = FullTransactionIdFromXid(cur->xmax);
 	snap->nxip = nxip;
 	for (i = 0; i < nxip; i++)
-		snap->xip[i] = widen_snapshot_xid(cur->xip[i], next_fxid);
+		snap->xip[i] = FullTransactionIdFromXid(cur->xip[i]);
 
 	/*
 	 * We want them guaranteed to be in ascending order.  This also removes
@@ -467,16 +427,16 @@ pg_snapshot_out(PG_FUNCTION_ARGS)
 	initStringInfo(&str);
 
 	appendStringInfo(&str, UINT64_FORMAT ":",
-					 U64FromFullTransactionId(snap->xmin));
+					 XidFromFullTransactionId(snap->xmin));
 	appendStringInfo(&str, UINT64_FORMAT ":",
-					 U64FromFullTransactionId(snap->xmax));
+					 XidFromFullTransactionId(snap->xmax));
 
 	for (i = 0; i < snap->nxip; i++)
 	{
 		if (i > 0)
 			appendStringInfoChar(&str, ',');
 		appendStringInfo(&str, UINT64_FORMAT,
-						 U64FromFullTransactionId(snap->xip[i]));
+						 XidFromFullTransactionId(snap->xip[i]));
 	}
 
 	PG_RETURN_CSTRING(str.data);
@@ -505,8 +465,8 @@ pg_snapshot_recv(PG_FUNCTION_ARGS)
 	if (nxip < 0 || nxip > PG_SNAPSHOT_MAX_NXIP)
 		goto bad_format;
 
-	xmin = FullTransactionIdFromU64((uint64) pq_getmsgint64(buf));
-	xmax = FullTransactionIdFromU64((uint64) pq_getmsgint64(buf));
+	xmin = FullTransactionIdFromXid((uint64) pq_getmsgint64(buf));
+	xmax = FullTransactionIdFromXid((uint64) pq_getmsgint64(buf));
 	if (!FullTransactionIdIsValid(xmin) ||
 		!FullTransactionIdIsValid(xmax) ||
 		FullTransactionIdPrecedes(xmax, xmin))
@@ -519,7 +479,7 @@ pg_snapshot_recv(PG_FUNCTION_ARGS)
 	for (i = 0; i < nxip; i++)
 	{
 		FullTransactionId cur =
-		FullTransactionIdFromU64((uint64) pq_getmsgint64(buf));
+		FullTransactionIdFromXid((uint64) pq_getmsgint64(buf));
 
 		if (FullTransactionIdPrecedes(cur, last) ||
 			FullTransactionIdPrecedes(cur, xmin) ||
@@ -564,10 +524,10 @@ pg_snapshot_send(PG_FUNCTION_ARGS)
 
 	pq_begintypsend(&buf);
 	pq_sendint32(&buf, snap->nxip);
-	pq_sendint64(&buf, (int64) U64FromFullTransactionId(snap->xmin));
-	pq_sendint64(&buf, (int64) U64FromFullTransactionId(snap->xmax));
+	pq_sendint64(&buf, (int64) XidFromFullTransactionId(snap->xmin));
+	pq_sendint64(&buf, (int64) XidFromFullTransactionId(snap->xmax));
 	for (i = 0; i < snap->nxip; i++)
-		pq_sendint64(&buf, (int64) U64FromFullTransactionId(snap->xip[i]));
+		pq_sendint64(&buf, (int64) XidFromFullTransactionId(snap->xip[i]));
 	PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
 }
 
@@ -655,8 +615,7 @@ pg_snapshot_xip(PG_FUNCTION_ARGS)
  * Report the status of a recent transaction ID, or null for wrapped,
  * truncated away or otherwise too old XIDs.
  *
- * The passed epoch-qualified xid is treated as a normal xid, not a
- * multixact id.
+ * The passed xid is treated as a normal xid, not a multixact id.
  *
  * If it points to a committed subxact the result is the subxact status even
  * though the parent xact may still be in progress or may have aborted.
diff --git a/src/backend/utils/cache/catcache.c b/src/backend/utils/cache/catcache.c
index 6ae7c1f50b..c42819ced4 100644
--- a/src/backend/utils/cache/catcache.c
+++ b/src/backend/utils/cache/catcache.c
@@ -1838,6 +1838,7 @@ CatalogCacheCreateEntry(CatCache *cache, HeapTuple ntp, Datum *arguments,
 		memcpy((char *) ct->tuple.t_data,
 			   (const char *) dtp->t_data,
 			   dtp->t_len);
+		HeapTupleCopyBase(&ct->tuple, dtp);
 		MemoryContextSwitchTo(oldcxt);
 
 		if (dtp != ntp)
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
index bdb771d278..9dfb4edb5a 100644
--- a/src/backend/utils/cache/relcache.c
+++ b/src/backend/utils/cache/relcache.c
@@ -2306,8 +2306,7 @@ RelationReloadIndexInfo(Relation relation)
 		relation->rd_index->indislive = index->indislive;
 
 		/* Copy xmin too, as that is needed to make sense of indcheckxmin */
-		HeapTupleHeaderSetXmin(relation->rd_indextuple->t_data,
-							   HeapTupleHeaderGetXmin(tuple->t_data));
+		HeapTupleSetXmin(relation->rd_indextuple, HeapTupleGetXmin(tuple));
 
 		ReleaseSysCache(tuple);
 	}
diff --git a/src/backend/utils/fmgr/fmgr.c b/src/backend/utils/fmgr/fmgr.c
index a9dd068095..34fe6bea83 100644
--- a/src/backend/utils/fmgr/fmgr.c
+++ b/src/backend/utils/fmgr/fmgr.c
@@ -540,7 +540,7 @@ lookup_C_func(HeapTuple procedureTuple)
 					NULL);
 	if (entry == NULL)
 		return NULL;			/* no such entry */
-	if (entry->fn_xmin == HeapTupleHeaderGetRawXmin(procedureTuple->t_data) &&
+	if (entry->fn_xmin == HeapTupleGetRawXmin(procedureTuple) &&
 		ItemPointerEquals(&entry->fn_tid, &procedureTuple->t_self))
 		return entry;			/* OK */
 	return NULL;				/* entry is out of date */
@@ -576,7 +576,7 @@ record_C_func(HeapTuple procedureTuple,
 					HASH_ENTER,
 					&found);
 	/* OID is already filled in */
-	entry->fn_xmin = HeapTupleHeaderGetRawXmin(procedureTuple->t_data);
+	entry->fn_xmin = HeapTupleGetRawXmin(procedureTuple);
 	entry->fn_tid = procedureTuple->t_self;
 	entry->user_fn = user_fn;
 	entry->inforec = inforec;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index fec228a135..5112b86690 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -2699,74 +2699,6 @@ static struct config_int ConfigureNamesInt[] =
 		NULL, NULL, NULL
 	},
 
-	{
-		{"vacuum_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("Minimum age at which VACUUM should freeze a table row."),
-			NULL
-		},
-		&vacuum_freeze_min_age,
-		50000000, 0, 1000000000,
-		NULL, NULL, NULL
-	},
-
-	{
-		{"vacuum_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("Age at which VACUUM should scan whole table to freeze tuples."),
-			NULL
-		},
-		&vacuum_freeze_table_age,
-		150000000, 0, 2000000000,
-		NULL, NULL, NULL
-	},
-
-	{
-		{"vacuum_multixact_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("Minimum age at which VACUUM should freeze a MultiXactId in a table row."),
-			NULL
-		},
-		&vacuum_multixact_freeze_min_age,
-		5000000, 0, 1000000000,
-		NULL, NULL, NULL
-	},
-
-	{
-		{"vacuum_multixact_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("Multixact age at which VACUUM should scan whole table to freeze tuples."),
-			NULL
-		},
-		&vacuum_multixact_freeze_table_age,
-		150000000, 0, 2000000000,
-		NULL, NULL, NULL
-	},
-
-	{
-		{"vacuum_defer_cleanup_age", PGC_SIGHUP, REPLICATION_PRIMARY,
-			gettext_noop("Number of transactions by which VACUUM and HOT cleanup should be deferred, if any."),
-			NULL
-		},
-		&vacuum_defer_cleanup_age,
-		0, 0, 1000000,			/* see ComputeXidHorizons */
-		NULL, NULL, NULL
-	},
-	{
-		{"vacuum_failsafe_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("Age at which VACUUM should trigger failsafe to avoid a wraparound outage."),
-			NULL
-		},
-		&vacuum_failsafe_age,
-		1600000000, 0, 2100000000,
-		NULL, NULL, NULL
-	},
-	{
-		{"vacuum_multixact_failsafe_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("Multixact age at which VACUUM should trigger failsafe to avoid a wraparound outage."),
-			NULL
-		},
-		&vacuum_multixact_failsafe_age,
-		1600000000, 0, 2100000000,
-		NULL, NULL, NULL
-	},
-
 	/*
 	 * See also CheckRequiredParameterValues() if this parameter changes
 	 */
@@ -3377,28 +3309,6 @@ static struct config_int ConfigureNamesInt[] =
 		50, 0, INT_MAX,
 		NULL, NULL, NULL
 	},
-	{
-		/* see varsup.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
-		{"autovacuum_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
-			gettext_noop("Age at which to autovacuum a table to prevent transaction ID wraparound."),
-			NULL
-		},
-		&autovacuum_freeze_max_age,
-
-		/* see vacuum_failsafe_age if you change the upper-limit value. */
-		200000000, 100000, 2000000000,
-		NULL, NULL, NULL
-	},
-	{
-		/* see multixact.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
-		{"autovacuum_multixact_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
-			gettext_noop("Multixact age at which to autovacuum a table to prevent multixact wraparound."),
-			NULL
-		},
-		&autovacuum_multixact_freeze_max_age,
-		400000000, 10000, 2000000000,
-		NULL, NULL, NULL
-	},
 	{
 		/* see max_connections */
 		{"autovacuum_max_workers", PGC_POSTMASTER, AUTOVACUUM,
@@ -3957,6 +3867,100 @@ static struct config_real ConfigureNamesReal[] =
 
 static struct config_int64 ConfigureNamesInt64[] =
 {
+	{
+		{"vacuum_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Minimum age at which VACUUM should freeze a table row."),
+			NULL
+		},
+		&vacuum_freeze_min_age,
+		INT64CONST(50000000), INT64CONST(0), INT64CONST(0x7FFFFFFFFFFFFFFF),
+		NULL, NULL, NULL
+	},
+
+	{
+		{"vacuum_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Age at which VACUUM should scan whole table to freeze tuples."),
+			NULL
+		},
+		&vacuum_freeze_table_age,
+		INT64CONST(150000000), INT64CONST(0), INT64CONST(0x7FFFFFFFFFFFFFFF),
+		NULL, NULL, NULL
+	},
+
+	{
+		{"vacuum_multixact_freeze_min_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Minimum age at which VACUUM should freeze a MultiXactId in a table row."),
+			NULL
+		},
+		&vacuum_multixact_freeze_min_age,
+		INT64CONST(5000000), INT64CONST(0), INT64CONST(0x7FFFFFFFFFFFFFFF),
+		NULL, NULL, NULL
+	},
+
+	{
+		{"vacuum_multixact_freeze_table_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Multixact age at which VACUUM should scan whole table to freeze tuples."),
+			NULL
+		},
+		&vacuum_multixact_freeze_table_age,
+		INT64CONST(150000000), INT64CONST(0), INT64CONST(0x7FFFFFFFFFFFFFFF),
+		NULL, NULL, NULL
+	},
+
+	{
+		{"vacuum_defer_cleanup_age", PGC_SIGHUP, REPLICATION_PRIMARY,
+			gettext_noop("Number of transactions by which VACUUM and HOT cleanup should be deferred, if any."),
+			NULL
+		},
+		&vacuum_defer_cleanup_age,
+		INT64CONST(0), INT64CONST(0), INT64CONST(1000000),
+		NULL, NULL, NULL
+	},
+
+	{
+		{"vacuum_failsafe_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Age at which VACUUM should trigger failsafe to avoid a wraparound outage."),
+			NULL
+		},
+		&vacuum_failsafe_age,
+		INT64CONST(1600000000), INT64CONST(0), INT64CONST(2100000000),
+		NULL, NULL, NULL
+	},
+
+	{
+		{"vacuum_multixact_failsafe_age", PGC_USERSET, CLIENT_CONN_STATEMENT,
+			gettext_noop("Multixact age at which VACUUM should trigger failsafe to avoid a wraparound outage."),
+			NULL
+		},
+		&vacuum_multixact_failsafe_age,
+		INT64CONST(1600000000), INT64CONST(0), INT64CONST(2100000000),
+		NULL, NULL, NULL
+	},
+
+	{
+		/* see varsup.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
+		{"autovacuum_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
+			gettext_noop("Age at which to autovacuum a table to prevent transaction ID wraparound."),
+			NULL
+		},
+		&autovacuum_freeze_max_age,
+
+		/* see vacuum_failsafe_age if you change the upper-limit value. */
+		INT64CONST(10000000000), INT64CONST(100000), INT64CONST(0x7FFFFFFFFFFFFFFF),
+		NULL, NULL, NULL
+	},
+
+	{
+		/* see multixact.c for why this is PGC_POSTMASTER not PGC_SIGHUP */
+		{"autovacuum_multixact_freeze_max_age", PGC_POSTMASTER, AUTOVACUUM,
+			gettext_noop("Multixact age at which to autovacuum a table to prevent multixact wraparound."),
+			NULL
+		},
+		&autovacuum_multixact_freeze_max_age,
+		INT64CONST(20000000000), INT64CONST(10000), INT64CONST(0x7FFFFFFFFFFFFFFF),
+		NULL, NULL, NULL
+	},
+
 	/* End-of-list marker */
 	{
 		{NULL, 0, 0, NULL, NULL}, NULL, 0.0, 0.0, 0.0, NULL, NULL, NULL
diff --git a/src/backend/utils/misc/help_config.c b/src/backend/utils/misc/help_config.c
index 61c83f3590..19a316ec99 100644
--- a/src/backend/utils/misc/help_config.c
+++ b/src/backend/utils/misc/help_config.c
@@ -33,6 +33,7 @@ typedef union
 	struct config_bool _bool;
 	struct config_real real;
 	struct config_int integer;
+	struct config_int64 integer8;
 	struct config_string string;
 	struct config_enum _enum;
 } mixedStruct;
@@ -107,7 +108,12 @@ printMixedStruct(mixedStruct *structToPrint)
 				   structToPrint->integer.min,
 				   structToPrint->integer.max);
 			break;
-
+		case PGC_INT64:
+			printf("INT64\t%lld\t%lld\t%lld\t",
+				   (long long) structToPrint->integer8.reset_val,
+				   (long long) structToPrint->integer8.min,
+				   (long long) structToPrint->integer8.max);
+			break;
 		case PGC_REAL:
 			printf("REAL\t%g\t%g\t%g\t",
 				   structToPrint->real.reset_val,
diff --git a/src/backend/utils/misc/pg_controldata.c b/src/backend/utils/misc/pg_controldata.c
index 4ab4a0a701..ffffdeccbb 100644
--- a/src/backend/utils/misc/pg_controldata.c
+++ b/src/backend/utils/misc/pg_controldata.c
@@ -165,7 +165,7 @@ pg_control_checkpoint(PG_FUNCTION_ARGS)
 	nulls[5] = false;
 
 	values[6] = CStringGetTextDatum(psprintf("%llu",
-											 (unsigned long long) U64FromFullTransactionId(ControlFile->checkPointCopy.nextXid)));
+											 (unsigned long long) XidFromFullTransactionId(ControlFile->checkPointCopy.nextXid)));
 	nulls[6] = false;
 
 	values[7] = ObjectIdGetDatum(ControlFile->checkPointCopy.nextOid);
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index b4bc06e5f5..39774a8ce0 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -651,9 +651,9 @@
 #autovacuum_vacuum_insert_scale_factor = 0.2	# fraction of inserts over table
 					# size before insert vacuum
 #autovacuum_analyze_scale_factor = 0.1	# fraction of table size before analyze
-#autovacuum_freeze_max_age = 200000000	# maximum XID age before forced vacuum
+#autovacuum_freeze_max_age = 10000000000	# maximum XID age before forced vacuum
 					# (change requires restart)
-#autovacuum_multixact_freeze_max_age = 400000000	# maximum multixact age
+#autovacuum_multixact_freeze_max_age = 20000000000	# maximum multixact age
 					# before forced vacuum
 					# (change requires restart)
 #autovacuum_vacuum_cost_delay = 2ms	# default vacuum cost delay for
diff --git a/src/backend/utils/sort/tuplesort.c b/src/backend/utils/sort/tuplesort.c
index 421afcf47d..9fef349852 100644
--- a/src/backend/utils/sort/tuplesort.c
+++ b/src/backend/utils/sort/tuplesort.c
@@ -4270,11 +4270,13 @@ static void
 writetup_cluster(Tuplesortstate *state, LogicalTape *tape, SortTuple *stup)
 {
 	HeapTuple	tuple = (HeapTuple) stup->tuple;
-	unsigned int tuplen = tuple->t_len + sizeof(ItemPointerData) + sizeof(int);
+	unsigned int tuplen = tuple->t_len + sizeof(ItemPointerData) + 2 * sizeof(TransactionId) + sizeof(int);
 
 	/* We need to store t_self, but not other fields of HeapTupleData */
 	LogicalTapeWrite(tape, &tuplen, sizeof(tuplen));
 	LogicalTapeWrite(tape, &tuple->t_self, sizeof(ItemPointerData));
+	LogicalTapeWrite(tape, &tuple->t_xmin, sizeof(TransactionId));
+	LogicalTapeWrite(tape, &tuple->t_xmax, sizeof(TransactionId));
 	LogicalTapeWrite(tape, tuple->t_data, tuple->t_len);
 	if (state->sortopt & TUPLESORT_RANDOMACCESS)	/* need trailing length
 													 * word? */
@@ -4291,7 +4293,7 @@ static void
 readtup_cluster(Tuplesortstate *state, SortTuple *stup,
 				LogicalTape *tape, unsigned int tuplen)
 {
-	unsigned int t_len = tuplen - sizeof(ItemPointerData) - sizeof(int);
+	unsigned int t_len = tuplen - sizeof(ItemPointerData) - 2 * sizeof(TransactionId) - sizeof(int);
 	HeapTuple	tuple = (HeapTuple) readtup_alloc(state,
 												  t_len + HEAPTUPLESIZE);
 
@@ -4299,6 +4301,8 @@ readtup_cluster(Tuplesortstate *state, SortTuple *stup,
 	tuple->t_data = (HeapTupleHeader) ((char *) tuple + HEAPTUPLESIZE);
 	tuple->t_len = t_len;
 	LogicalTapeReadExact(tape, &tuple->t_self, sizeof(ItemPointerData));
+	LogicalTapeReadExact(tape, &tuple->t_xmin, sizeof(TransactionId));
+	LogicalTapeReadExact(tape, &tuple->t_xmax, sizeof(TransactionId));
 	/* We don't currently bother to reconstruct t_tableOid */
 	tuple->t_tableOid = InvalidOid;
 	/* Read in the tuple body */
diff --git a/src/backend/utils/time/combocid.c b/src/backend/utils/time/combocid.c
index 6613dc0534..f673624f68 100644
--- a/src/backend/utils/time/combocid.c
+++ b/src/backend/utils/time/combocid.c
@@ -101,12 +101,13 @@ static CommandId GetRealCmax(CommandId combocid);
  */
 
 CommandId
-HeapTupleHeaderGetCmin(HeapTupleHeader tup)
+HeapTupleGetCmin(HeapTuple tuple)
 {
+	HeapTupleHeader tup = tuple->t_data;
 	CommandId	cid = HeapTupleHeaderGetRawCommandId(tup);
 
 	Assert(!(tup->t_infomask & HEAP_MOVED));
-	Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(tup)));
+	Assert(TransactionIdIsCurrentTransactionId(HeapTupleGetXmin(tuple)));
 
 	if (tup->t_infomask & HEAP_COMBOCID)
 		return GetRealCmin(cid);
@@ -115,8 +116,9 @@ HeapTupleHeaderGetCmin(HeapTupleHeader tup)
 }
 
 CommandId
-HeapTupleHeaderGetCmax(HeapTupleHeader tup)
+HeapTupleGetCmax(HeapTuple tuple)
 {
+	HeapTupleHeader tup = tuple->t_data;
 	CommandId	cid = HeapTupleHeaderGetRawCommandId(tup);
 
 	Assert(!(tup->t_infomask & HEAP_MOVED));
@@ -128,7 +130,7 @@ HeapTupleHeaderGetCmax(HeapTupleHeader tup)
 	 * things too much.
 	 */
 	Assert(CritSectionCount > 0 ||
-		   TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetUpdateXid(tup)));
+		   TransactionIdIsCurrentTransactionId(HeapTupleGetUpdateXidAny(tuple)));
 
 	if (tup->t_infomask & HEAP_COMBOCID)
 		return GetRealCmax(cid);
@@ -150,7 +152,7 @@ HeapTupleHeaderGetCmax(HeapTupleHeader tup)
  * changes the tuple in shared buffers.
  */
 void
-HeapTupleHeaderAdjustCmax(HeapTupleHeader tup,
+HeapTupleHeaderAdjustCmax(HeapTuple tup,
 						  CommandId *cmax,
 						  bool *iscombo)
 {
@@ -160,10 +162,10 @@ HeapTupleHeaderAdjustCmax(HeapTupleHeader tup,
 	 * Test for HeapTupleHeaderXminCommitted() first, because it's cheaper
 	 * than a TransactionIdIsCurrentTransactionId call.
 	 */
-	if (!HeapTupleHeaderXminCommitted(tup) &&
-		TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetRawXmin(tup)))
+	if (!HeapTupleHeaderXminCommitted(tup->t_data) &&
+		TransactionIdIsCurrentTransactionId(HeapTupleGetRawXmin(tup)))
 	{
-		CommandId	cmin = HeapTupleHeaderGetCmin(tup);
+		CommandId	cmin = HeapTupleGetCmin(tup);
 
 		*cmax = GetComboCommandId(cmin, *cmax);
 		*iscombo = true;
diff --git a/src/backend/utils/time/snapmgr.c b/src/backend/utils/time/snapmgr.c
index 8e03a9f0f4..415aec1064 100644
--- a/src/backend/utils/time/snapmgr.c
+++ b/src/backend/utils/time/snapmgr.c
@@ -948,15 +948,15 @@ SnapshotResetXmin(void)
 
 	if (pairingheap_is_empty(&RegisteredSnapshots))
 	{
-		MyProc->xmin = InvalidTransactionId;
+		pg_atomic_write_u64(&MyProc->xmin, InvalidTransactionId);
 		return;
 	}
 
 	minSnapshot = pairingheap_container(SnapshotData, ph_node,
 										pairingheap_first(&RegisteredSnapshots));
 
-	if (TransactionIdPrecedes(MyProc->xmin, minSnapshot->xmin))
-		MyProc->xmin = minSnapshot->xmin;
+	if (TransactionIdPrecedes(pg_atomic_read_u64(&MyProc->xmin), minSnapshot->xmin))
+		pg_atomic_write_u64(&MyProc->xmin, minSnapshot->xmin);
 }
 
 /*
@@ -1109,7 +1109,7 @@ AtEOXact_Snapshot(bool isCommit, bool resetXmin)
 	if (resetXmin)
 		SnapshotResetXmin();
 
-	Assert(resetXmin || MyProc->xmin == 0);
+	Assert(resetXmin || pg_atomic_read_u64(&MyProc->xmin) == 0);
 }
 
 
@@ -1174,8 +1174,9 @@ ExportSnapshot(Snapshot snapshot)
 	 * Generate file path for the snapshot.  We start numbering of snapshots
 	 * inside the transaction from 1.
 	 */
-	snprintf(path, sizeof(path), SNAPSHOT_EXPORT_DIR "/%08X-%08X-%d",
-			 MyProc->backendId, MyProc->lxid, list_length(exportedSnapshots) + 1);
+	snprintf(path, sizeof(path), SNAPSHOT_EXPORT_DIR "/%08X-%08X%08X-%d",
+			 MyProc->backendId, (uint32) (MyProc->lxid >> 32),
+			 (uint32) MyProc->lxid, list_length(exportedSnapshots) + 1);
 
 	/*
 	 * Copy the snapshot into TopTransactionContext, add it to the
@@ -1351,7 +1352,7 @@ parseXidFromText(const char *prefix, char **s, const char *filename)
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("invalid snapshot data in file \"%s\"", filename)));
 	ptr += prefixlen;
-	if (sscanf(ptr, "%u", &val) != 1)
+	if (sscanf(ptr, "%" INT64_MODIFIER "u", &val) != 1)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("invalid snapshot data in file \"%s\"", filename)));
@@ -1376,7 +1377,7 @@ parseVxidFromText(const char *prefix, char **s, const char *filename,
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("invalid snapshot data in file \"%s\"", filename)));
 	ptr += prefixlen;
-	if (sscanf(ptr, "%d/%u", &vxid->backendId, &vxid->localTransactionId) != 2)
+	if (sscanf(ptr, "%d/%" INT64_MODIFIER "u", &vxid->backendId, &vxid->localTransactionId) != 2)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 				 errmsg("invalid snapshot data in file \"%s\"", filename)));
@@ -1835,7 +1836,7 @@ TransactionIdLimitedForOldSnapshots(TransactionId recentXmin,
 	 */
 	if (old_snapshot_threshold == 0)
 	{
-		if (TransactionIdPrecedes(latest_xmin, MyProc->xmin)
+		if (TransactionIdPrecedes(latest_xmin, pg_atomic_read_u64(&MyProc->xmin))
 			&& TransactionIdFollows(latest_xmin, xlimit))
 			xlimit = latest_xmin;
 
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index e496fdeac6..2952e020c5 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -1354,7 +1354,7 @@ bootstrap_template1(void)
 							  escape_quotes_bki(username));
 
 	/* relfrozenxid must not be less than FirstNormalTransactionId */
-	sprintf(buf, "%u", Max(start_xid, 3));
+	sprintf(buf, "%llu", (unsigned long long) Max(start_xid, 3));
 	bki_lines = replace_token(bki_lines, "RECENTXMIN",
 							  buf);
 
@@ -1377,13 +1377,13 @@ bootstrap_template1(void)
 	unsetenv("PGCLIENTENCODING");
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" --boot -X %d %s %s %u %s %u %s %u %s %s %s",
+			 "\"%s\" --boot -X %d %s %s %llu %s %llu %s %llu %s %s %s",
 			 backend_exec,
 			 wal_segment_size_mb * (1024 * 1024),
 			 data_checksums ? "-k" : "",
-			 "-m", start_mxid,
-			 "-o", start_mxoff,
-			 "-x", start_xid,
+			 "-m", (unsigned long long) start_mxid,
+			 "-o", (unsigned long long) start_mxoff,
+			 "-x", (unsigned long long) start_xid,
 			 boot_options, extra_options,
 			 debug ? "-d 5" : "");
 
@@ -2205,15 +2205,18 @@ usage(const char *progname)
 	printf(_("      --discard-caches      set debug_discard_caches=1\n"));
 	printf(_("  -L DIRECTORY              where to find the input files\n"));
 	printf(_("  -m, --multixact-id=START_MXID\n"
-			 "                            set initial database cluster multixact id\n"));
+			 "                            set initial database cluster multixact id\n"
+			 "                            max value is 2^62-1\n"));
 	printf(_("  -n, --no-clean            do not clean up after errors\n"));
 	printf(_("  -N, --no-sync             do not wait for changes to be written safely to disk\n"));
 	printf(_("      --no-instructions     do not print instructions for next steps\n"));
 	printf(_("  -o, --multixact-offset=START_MXOFF\n"
-			 "                            set initial database cluster multixact offset\n"));
+			 "                            set initial database cluster multixact offset\n"
+			 "                            max value is 2^62-1"));
 	printf(_("  -s, --show                show internal settings\n"));
 	printf(_("  -S, --sync-only           only sync database files to disk, then exit\n"));
-	printf(_("  -x, --xid=START_XID       set initial database cluster xid\n"));
+	printf(_("  -x, --xid=START_XID       set initial database cluster xid\n"
+			 "                            max value is 2^62-1\n"));
 	printf(_("\nOther options:\n"));
 	printf(_("  -V, --version             output version information, then exit\n"));
 	printf(_("  -?, --help                show this help, then exit\n"));
@@ -2747,13 +2750,16 @@ initialize_data_directory(void)
 	setup_config();
 
 	if (start_mxid != 0)
-		printf(_("selecting initial multixact id ... %u\n"), start_mxid);
+		printf(_("selecting initial multixact id ... %llu\n"),
+				 (unsigned long long) start_mxid);
 
 	if (start_mxoff != 0)
-		printf(_("selecting initial multixact offset ... %u\n"), start_mxoff);
+		printf(_("selecting initial multixact offset ... %llu\n"),
+				 (unsigned long long) start_mxoff);
 
 	if (start_xid != 0)
-		printf(_("selecting initial xid ... %u\n"), start_xid);
+		printf(_("selecting initial xid ... %llu\n"),
+				 (unsigned long long) start_xid);
 
 	/* Bootstrap template1 */
 	bootstrap_template1();
@@ -2771,11 +2777,11 @@ initialize_data_directory(void)
 	fflush(stdout);
 
 	snprintf(cmd, sizeof(cmd),
-			 "\"%s\" %s %s %s %u %s %u %s %u template1 >%s",
+			 "\"%s\" %s %s %s %llu %s %llu %s %llu template1 >%s",
 			 backend_exec, backend_options, extra_options,
-			 "-m", start_mxid,
-			 "-o", start_mxoff,
-			 "-x", start_xid,
+			 "-m", (unsigned long long) start_mxid,
+			 "-o", (unsigned long long) start_mxoff,
+			 "-x", (unsigned long long) start_xid,
 			 DEVNULL);
 
 	PG_CMD_OPEN;
@@ -2942,15 +2948,13 @@ main(int argc, char *argv[])
 				break;
 			case 'm':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_mxid = value;
+					start_mxid = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_mxid) /* overflow */
+						!StartMultiXactIdIsValid(start_mxid))
 					{
 						pg_log_error("invalid initial database cluster multixact id");
 						exit(1);
@@ -2975,15 +2979,13 @@ main(int argc, char *argv[])
 				break;
 			case 'o':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_mxoff = value;
+					start_mxoff = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_mxoff) /* overflow */
+						!StartMultiXactOffsetIsValid(start_mxoff))
 					{
 						pg_log_error("invalid initial database cluster multixact offset");
 						exit(1);
@@ -3062,15 +3064,13 @@ main(int argc, char *argv[])
 				break;
 			case 'x':
 				{
-					unsigned long	value;
-					char		   *endptr;
+					char	   *endptr;
 
 					errno = 0;
-					value = strtoul(optarg, &endptr, 0);
-					start_xid = value;
+					start_xid = strtoull(optarg, &endptr, 0);
 
 					if (endptr == optarg || *endptr != '\0' || errno != 0 ||
-						value != start_xid) /* overflow */
+						!StartTransactionIdIsValid(start_xid))
 					{
 						pg_log_error("invalid value for initial database cluster xid");
 						exit(1);
diff --git a/src/bin/initdb/t/001_initdb.pl b/src/bin/initdb/t/001_initdb.pl
index 9f9ee99cb7..425470e7d7 100644
--- a/src/bin/initdb/t/001_initdb.pl
+++ b/src/bin/initdb/t/001_initdb.pl
@@ -140,28 +140,28 @@ command_fails(
 
 # Set non-standard initial mxid/mxoff/xid.
 command_fails_like(
-	[ 'initdb', '-m', '4294967296', $datadir ],
+	[ 'initdb', '-m', '9223372036854775807', $datadir ],
 	qr/initdb: error: invalid initial database cluster multixact id/,
 	'fails for invalid initial database cluster multixact id');
 command_fails_like(
-	[ 'initdb', '-o', '4294967296', $datadir ],
+	[ 'initdb', '-o', '9223372036854775807', $datadir ],
 	qr/initdb: error: invalid initial database cluster multixact offset/,
 	'fails for invalid initial database cluster multixact offset');
 command_fails_like(
-	[ 'initdb', '-x', '4294967296', $datadir ],
+	[ 'initdb', '-x', '9223372036854775807', $datadir ],
 	qr/initdb: error: invalid value for initial database cluster xid/,
 	'fails for invalid initial database cluster xid');
 
 command_fails_like(
-	[ 'initdb', '-m', '0x100000000', $datadir ],
+	[ 'initdb', '-m', '0x10000000000000000', $datadir ],
 	qr/initdb: error: invalid initial database cluster multixact id/,
 	'fails for invalid initial database cluster multixact id');
 command_fails_like(
-	[ 'initdb', '-o', '0x100000000', $datadir ],
+	[ 'initdb', '-o', '0x10000000000000000', $datadir ],
 	qr/initdb: error: invalid initial database cluster multixact offset/,
 	'fails for invalid initial database cluster multixact offset');
 command_fails_like(
-	[ 'initdb', '-x', '0x100000000', $datadir ],
+	[ 'initdb', '-x', '0x10000000000000000', $datadir ],
 	qr/initdb: error: invalid value for initial database cluster xid/,
 	'fails for invalid initial database cluster xid');
 
diff --git a/src/bin/pg_amcheck/t/004_verify_heapam.pl b/src/bin/pg_amcheck/t/004_verify_heapam.pl
index 8050811105..6563eb798b 100644
--- a/src/bin/pg_amcheck/t/004_verify_heapam.pl
+++ b/src/bin/pg_amcheck/t/004_verify_heapam.pl
@@ -9,6 +9,8 @@ use PostgreSQL::Test::Utils;
 
 use Test::More;
 
+use Data::Dumper;
+
 # This regression test demonstrates that the pg_amcheck binary correctly
 # identifies specific kinds of corruption within pages.  To test this, we need
 # a mechanism to create corrupt pages with predictable, repeatable corruption.
@@ -85,6 +87,62 @@ use Test::More;
 
 use constant HEAPTUPLE_PACK_CODE => 'LLLSSSSSCCLLCCCCCCCCCCllLL';
 use constant HEAPTUPLE_PACK_LENGTH => 58;    # Total size
+use constant HEAPPAGE_SPECIAL_PACK_CODE => 'QQ';
+use constant HEAPPAGE_SPECIAL_PACK_LENGTH => 16;
+use constant HEAPPAGE_SIZE => 8192;
+
+# Some #define constants from access/htup_details.h for use while corrupting.
+use constant HEAP_HASNULL        => 0x0001;
+use constant HEAP_XMAX_LOCK_ONLY => 0x0080;
+use constant HEAP_XMIN_COMMITTED => 0x0100;
+use constant HEAP_XMIN_INVALID   => 0x0200;
+use constant HEAP_XMAX_COMMITTED => 0x0400;
+use constant HEAP_XMAX_INVALID   => 0x0800;
+use constant HEAP_NATTS_MASK     => 0x07FF;
+use constant HEAP_XMAX_IS_MULTI  => 0x1000;
+use constant HEAP_KEYS_UPDATED   => 0x2000;
+
+use constant FIRST_NORMAL_TRANSACTION_ID => 3;
+
+# Read page special data
+sub read_special_data
+{
+	my ($fh, $offset) = @_;
+	my ($buffer, %special);
+
+	$offset -= $offset % HEAPPAGE_SIZE;
+	$offset += HEAPPAGE_SIZE - HEAPPAGE_SPECIAL_PACK_LENGTH;
+
+	sysseek($fh, $offset, 0)
+		or BAIL_OUT("sysseek failed: $!");
+	defined(sysread($fh, $buffer, HEAPPAGE_SPECIAL_PACK_LENGTH))
+		or BAIL_OUT("sysread failed: $!");
+
+	@_ = unpack(HEAPPAGE_SPECIAL_PACK_CODE, $buffer);
+	%special = (
+		pd_xid_base   => shift,
+		pd_multi_base => shift);
+	return \%special;
+}
+
+# Write page special data
+sub write_special_data
+{
+	my ($fh, $offset, $special) = @_;
+
+	$offset -= $offset % HEAPPAGE_SIZE;
+	$offset += HEAPPAGE_SIZE - HEAPPAGE_SPECIAL_PACK_LENGTH;
+
+	my $buffer = pack(
+		HEAPPAGE_SPECIAL_PACK_CODE,
+		$special->{pd_xid_base},  $special->{pd_multi_base});
+
+	sysseek($fh, $offset, 0)
+		or BAIL_OUT("sysseek failed: $!");
+	defined(syswrite($fh, $buffer, HEAPPAGE_SPECIAL_PACK_LENGTH))
+		or BAIL_OUT("syswrite failed: $!");
+	return;
+}
 
 # Read a tuple of our table from a heap page.
 #
@@ -96,8 +154,9 @@ use constant HEAPTUPLE_PACK_LENGTH => 58;    # Total size
 #
 sub read_tuple
 {
-	my ($fh, $offset) = @_;
+	my ($fh, $offset, $raw) = @_;
 	my ($buffer, %tup);
+
 	sysseek($fh, $offset, 0)
 	  or BAIL_OUT("sysseek failed: $!");
 	defined(sysread($fh, $buffer, HEAPTUPLE_PACK_LENGTH))
@@ -133,6 +192,18 @@ sub read_tuple
 		c_va_toastrelid => shift);
 	# Stitch together the text for column 'b'
 	$tup{b} = join('', map { chr($tup{"b_body$_"}) } (1 .. 7));
+
+	if (!$raw)
+	{
+		my $special = read_special_data($fh, $offset);
+
+		$tup{t_xmin} += $special->{pd_xid_base};
+		my $is_multi = $tup{t_infomask} & HEAP_XMAX_IS_MULTI;
+		$tup{t_xmax} += !$is_multi ?
+			$special->{pd_xid_base} :
+			$special->{pd_multi_base};
+	}
+
 	return \%tup;
 }
 
@@ -148,7 +219,33 @@ sub read_tuple
 #
 sub write_tuple
 {
-	my ($fh, $offset, $tup) = @_;
+	my ($fh, $offset, $tup, $raw) = @_;
+
+	if (!$raw)
+	{
+		my $special = read_special_data($fh, $offset);
+
+		my $xmin = $tup->{t_xmin} - $special->{pd_xid_base};
+		die "tuple x_min $tup->{t_xmin} is too smal for pd_xid_base $special->{pd_xid_base}"
+			if $xmin < 3;
+		$tup->{t_xmin} = $xmin;
+
+        if (($tup->{t_infomask} & HEAP_XMAX_IS_MULTI) == 0)
+		{
+			my $xmax = $tup->{t_xmax} - $special->{pd_xid_base};
+			die "tuple x_max $tup->{t_xmax} is too smal for pd_xid_base $special->{pd_xid_base}"
+				if $xmax < 3;
+			$tup->{t_xmax} = $xmax;
+		}
+		else
+		{
+			my $xmax = $tup->{t_xmax} - $special->{pd_multi_base};
+			die "tuple multi x_max $tup->{t_xmax} is too smal for pd_multi_base $special->{pd_multi_base}"
+				if $xmax < 3;
+			$tup->{t_xmax} = $xmax;
+		}
+	}
+
 	my $buffer = pack(
 		HEAPTUPLE_PACK_CODE,
 		$tup->{t_xmin},       $tup->{t_xmax},
@@ -171,6 +268,41 @@ sub write_tuple
 	return;
 }
 
+# move pd_xid_base and pd_multi_base to more suitable position for tests.
+sub fixup_page
+{
+	my ($fh, $page, $xid_base, $multi_base, $lp_off) = @_;
+	my $offset = $page * HEAPPAGE_SIZE;
+	my $special = read_special_data($fh, $offset);
+
+	die "xid_base $xid_base should be lesser than existed $special->{pd_xid_base}"
+		if ($xid_base > $special->{pd_xid_base});
+	die "multi_base $multi_base should be lesser than existed $special->{pd_multi_base}"
+		if ($multi_base > $special->{pd_multi_base} && $special->{pd_multi_base} != 0);
+	return if ($xid_base == $special->{pd_xid_base} &&
+			$multi_base == $special->{pd_multi_base});
+
+	my $xid_delta = $special->{pd_xid_base} - $xid_base;
+	my $multi_delta = $special->{pd_multi_base} - $multi_base;
+
+	for my $off (@$lp_off)
+	{
+		# change only tuples on this page.
+		next if ($off < $offset && $off > $offset + HEAPPAGE_SIZE);
+
+		my $tup = read_tuple($fh, $off, 1);
+		$tup->{t_xmin} += $xid_delta;
+		my $is_multi = $tup->{t_infomask} & HEAP_XMAX_IS_MULTI;
+		$tup->{t_xmax} += !$is_multi ? $xid_delta : $multi_delta;
+		write_tuple($fh, $off, $tup, 1);
+	}
+
+	$special->{pd_xid_base} = $xid_base;
+	$special->{pd_multi_base} = $multi_base;
+
+	write_special_data($fh, $offset, $special);
+}
+
 # Set umask so test directories and files are created with default permissions
 umask(0077);
 
@@ -233,6 +365,10 @@ my $relfrozenxid = $node->safe_psql('postgres',
 	q(select relfrozenxid from pg_class where relname = 'test'));
 my $datfrozenxid = $node->safe_psql('postgres',
 	q(select datfrozenxid from pg_database where datname = 'postgres'));
+my $datminmxid = $node->safe_psql('postgres',
+	q(select datminmxid from pg_database where datname = 'postgres'));
+my $txid_current = $node->safe_psql('postgres',
+	q(select txid_current()));
 
 # Sanity check that our 'test' table has a relfrozenxid newer than the
 # datfrozenxid for the database, and that the datfrozenxid is greater than the
@@ -263,7 +399,7 @@ select lp_off from heap_page_items(get_raw_page('test', 'main', 0))
 $node->stop;
 my $file;
 open($file, '+<', $relpath)
-  or BAIL_OUT("open failed: $!");
+	or BAIL_OUT("open failed: $!");
 binmode $file;
 
 my $ENDIANNESS;
@@ -291,8 +427,13 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 	# Determine endianness of current platform from the 1-byte varlena header
 	$ENDIANNESS = $tup->{b_header} == 0x11 ? "little" : "big";
 }
+
+# Set 64bit xid bases a bit in the past therefore we can set xmin/xmax a bit
+# in the past
+fixup_page($file, 0, $datfrozenxid - 100, $datminmxid - 100, \@lp_off);
+
 close($file)
-  or BAIL_OUT("close failed: $!");
+	or BAIL_OUT("close failed: $!");
 $node->start;
 
 # Ok, Xids and page layout look ok.  We can run corruption tests.
@@ -308,17 +449,6 @@ $node->command_ok([ 'pg_amcheck', '-p', $port, 'postgres' ],
 
 $node->stop;
 
-# Some #define constants from access/htup_details.h for use while corrupting.
-use constant HEAP_HASNULL        => 0x0001;
-use constant HEAP_XMAX_LOCK_ONLY => 0x0080;
-use constant HEAP_XMIN_COMMITTED => 0x0100;
-use constant HEAP_XMIN_INVALID   => 0x0200;
-use constant HEAP_XMAX_COMMITTED => 0x0400;
-use constant HEAP_XMAX_INVALID   => 0x0800;
-use constant HEAP_NATTS_MASK     => 0x07FF;
-use constant HEAP_XMAX_IS_MULTI  => 0x1000;
-use constant HEAP_KEYS_UPDATED   => 0x2000;
-
 # Helper function to generate a regular expression matching the header we
 # expect verify_heapam() to return given which fields we expect to be non-null.
 sub header
@@ -342,7 +472,7 @@ sub header
 #
 my @expected;
 open($file, '+<', $relpath)
-  or BAIL_OUT("open failed: $!");
+	or BAIL_OUT("open failed: $!");
 binmode $file;
 
 for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
@@ -367,7 +497,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 	if ($offnum == 2)
 	{
 		# Corruptly set xmin < datfrozenxid
-		my $xmin = 3;
+		my $xmin = $datfrozenxid - 12;
 		$tup->{t_xmin} = $xmin;
 		$tup->{t_infomask} &= ~HEAP_XMIN_COMMITTED;
 		$tup->{t_infomask} &= ~HEAP_XMIN_INVALID;
@@ -377,24 +507,24 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 	}
 	elsif ($offnum == 3)
 	{
-		# Corruptly set xmin < datfrozenxid, further back, noting circularity
-		# of xid comparison.  For a new cluster with epoch = 0, the corrupt
-		# xmin will be interpreted as in the future
-		$tup->{t_xmin} = 4026531839;
+		# Corruptly set xmin > next transaction id.
+		my $xmin = $relfrozenxid + 1000000;
+		$tup->{t_xmin} = $xmin;
 		$tup->{t_infomask} &= ~HEAP_XMIN_COMMITTED;
 		$tup->{t_infomask} &= ~HEAP_XMIN_INVALID;
 
 		push @expected,
-		  qr/${$header}xmin 4026531839 equals or exceeds next valid transaction ID \d+/;
+		  qr/${$header}xmin $xmin equals or exceeds next valid transaction ID \d+/;
 	}
 	elsif ($offnum == 4)
 	{
-		# Corruptly set xmax < relminmxid;
-		$tup->{t_xmax} = 4026531839;
+		# Corruptly set xmax > next transaction id.
+		my $xmax = $relfrozenxid + 1000000;
+		$tup->{t_xmax} = $xmax;
 		$tup->{t_infomask} &= ~HEAP_XMAX_INVALID;
 
 		push @expected,
-		  qr/${$header}xmax 4026531839 equals or exceeds next valid transaction ID \d+/;
+			qr/${$header}xmax $xmax equals or exceeds next valid transaction ID \d+/;
 	}
 	elsif ($offnum == 5)
 	{
@@ -402,8 +532,8 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_hoff} += 128;
 
 		push @expected,
-		  qr/${$header}data begins at offset 152 beyond the tuple length 58/,
-		  qr/${$header}tuple data should begin at byte 24, but actually begins at byte 152 \(3 attributes, no nulls\)/;
+			qr/${$header}data begins at offset 152 beyond the tuple length 58/,
+			qr/${$header}tuple data should begin at byte 24, but actually begins at byte 152 \(3 attributes, no nulls\)/;
 	}
 	elsif ($offnum == 6)
 	{
@@ -411,7 +541,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_hoff} += 3;
 
 		push @expected,
-		  qr/${$header}tuple data should begin at byte 24, but actually begins at byte 27 \(3 attributes, no nulls\)/;
+			qr/${$header}tuple data should begin at byte 24, but actually begins at byte 27 \(3 attributes, no nulls\)/;
 	}
 	elsif ($offnum == 7)
 	{
@@ -419,7 +549,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_hoff} -= 8;
 
 		push @expected,
-		  qr/${$header}tuple data should begin at byte 24, but actually begins at byte 16 \(3 attributes, no nulls\)/;
+			qr/${$header}tuple data should begin at byte 24, but actually begins at byte 16 \(3 attributes, no nulls\)/;
 	}
 	elsif ($offnum == 8)
 	{
@@ -427,7 +557,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_hoff} -= 3;
 
 		push @expected,
-		  qr/${$header}tuple data should begin at byte 24, but actually begins at byte 21 \(3 attributes, no nulls\)/;
+			qr/${$header}tuple data should begin at byte 24, but actually begins at byte 21 \(3 attributes, no nulls\)/;
 	}
 	elsif ($offnum == 9)
 	{
@@ -435,7 +565,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_infomask2} |= HEAP_NATTS_MASK;
 
 		push @expected,
-		  qr/${$header}number of attributes 2047 exceeds maximum expected for table 3/;
+			qr/${$header}number of attributes 2047 exceeds maximum expected for table 3/;
 	}
 	elsif ($offnum == 10)
 	{
@@ -447,7 +577,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_bits} = 0xAA;
 
 		push @expected,
-		  qr/${$header}tuple data should begin at byte 280, but actually begins at byte 24 \(2047 attributes, has nulls\)/;
+			qr/${$header}tuple data should begin at byte 280, but actually begins at byte 24 \(2047 attributes, has nulls\)/;
 	}
 	elsif ($offnum == 11)
 	{
@@ -458,7 +588,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		$tup->{t_hoff} = 32;
 
 		push @expected,
-		  qr/${$header}number of attributes 67 exceeds maximum expected for table 3/;
+			qr/${$header}number of attributes 67 exceeds maximum expected for table 3/;
 	}
 	elsif ($offnum == 12)
 	{
@@ -482,7 +612,7 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 
 		$header = header(0, $offnum, 1);
 		push @expected,
-		  qr/${header}attribute with length \d+ ends at offset \d+ beyond total tuple length \d+/;
+			qr/${header}attribute with length \d+ ends at offset \d+ beyond total tuple length \d+/;
 	}
 	elsif ($offnum == 13)
 	{
@@ -497,25 +627,27 @@ for (my $tupidx = 0; $tupidx < ROWCOUNT; $tupidx++)
 		# Set both HEAP_XMAX_COMMITTED and HEAP_XMAX_IS_MULTI
 		$tup->{t_infomask} |= HEAP_XMAX_COMMITTED;
 		$tup->{t_infomask} |= HEAP_XMAX_IS_MULTI;
-		$tup->{t_xmax} = 4;
+		my $xmax = $datminmxid + 1000000;
+		$tup->{t_xmax} = $xmax;
 
 		push @expected,
-		  qr/${header}multitransaction ID 4 equals or exceeds next valid multitransaction ID 1/;
+			qr/${header}multitransaction ID $xmax equals or exceeds next valid multitransaction ID \d+/;
 	}
 	elsif ($offnum == 15)    # Last offnum must equal ROWCOUNT
 	{
 		# Set both HEAP_XMAX_COMMITTED and HEAP_XMAX_IS_MULTI
 		$tup->{t_infomask} |= HEAP_XMAX_COMMITTED;
 		$tup->{t_infomask} |= HEAP_XMAX_IS_MULTI;
-		$tup->{t_xmax} = 4000000000;
+		my $xmax = $datminmxid - 10;
+		$tup->{t_xmax} = $xmax;
 
 		push @expected,
-		  qr/${header}multitransaction ID 4000000000 precedes relation minimum multitransaction ID threshold 1/;
+			qr/${header}multitransaction ID $xmax precedes relation minimum multitransaction ID threshold \d+/;
 	}
 	write_tuple($file, $offset, $tup);
 }
 close($file)
-  or BAIL_OUT("close failed: $!");
+	or BAIL_OUT("close failed: $!");
 $node->start;
 
 # Run pg_amcheck against the corrupt table with epoch=0, comparing actual
diff --git a/src/bin/pg_controldata/pg_controldata.c b/src/bin/pg_controldata/pg_controldata.c
index a8a46d5bf0..ffc89b3184 100644
--- a/src/bin/pg_controldata/pg_controldata.c
+++ b/src/bin/pg_controldata/pg_controldata.c
@@ -248,7 +248,7 @@ main(int argc, char *argv[])
 	printf(_("Latest checkpoint's full_page_writes: %s\n"),
 		   ControlFile->checkPointCopy.fullPageWrites ? _("on") : _("off"));
 	printf(_("Latest checkpoint's NextXID:          %llu\n"),
-		   (unsigned long long) U64FromFullTransactionId(ControlFile->checkPointCopy.nextXid));
+		   (unsigned long long) XidFromFullTransactionId(ControlFile->checkPointCopy.nextXid));
 	printf(_("Latest checkpoint's NextOID:          %u\n"),
 		   ControlFile->checkPointCopy.nextOid);
 	printf(_("Latest checkpoint's NextMultiXactId:  %llu\n"),
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index d16e29a3cc..7d996e53da 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -2829,7 +2829,7 @@ dumpDatabase(Archive *fout)
 			   *datistemplate,
 			   *datconnlimit,
 			   *tablespace;
-	uint32		frozenxid,
+	uint64		frozenxid,
 				minmxid;
 	char	   *qdatname;
 
@@ -2890,8 +2890,8 @@ dumpDatabase(Archive *fout)
 		iculocale = PQgetvalue(res, 0, i_daticulocale);
 	else
 		iculocale = NULL;
-	frozenxid = atooid(PQgetvalue(res, 0, i_frozenxid));
-	minmxid = atooid(PQgetvalue(res, 0, i_minmxid));
+	frozenxid = strtou64(PQgetvalue(res, 0, i_frozenxid), NULL, 0);
+	minmxid = strtou64(PQgetvalue(res, 0, i_minmxid), NULL, 0);
 	dbdacl.acl = PQgetvalue(res, 0, i_datacl);
 	dbdacl.acldefault = PQgetvalue(res, 0, i_acldefault);
 	datistemplate = PQgetvalue(res, 0, i_datistemplate);
@@ -3166,10 +3166,10 @@ dumpDatabase(Archive *fout)
 
 		appendPQExpBufferStr(loOutQry, "\n-- For binary upgrade, set pg_largeobject relfrozenxid and relminmxid\n");
 		appendPQExpBuffer(loOutQry, "UPDATE pg_catalog.pg_class\n"
-						  "SET relfrozenxid = '%u', relminmxid = '%u'\n"
+						  "SET relfrozenxid = '%s', relminmxid = '%s'\n"
 						  "WHERE oid = %u;\n",
-						  atooid(PQgetvalue(lo_res, 0, i_relfrozenxid)),
-						  atooid(PQgetvalue(lo_res, 0, i_relminmxid)),
+						  (PQgetvalue(lo_res, 0, i_relfrozenxid)),
+						  (PQgetvalue(lo_res, 0, i_relminmxid)),
 						  LargeObjectRelationId);
 		ArchiveEntry(fout, nilCatalogId, createDumpId(),
 					 ARCHIVE_OPTS(.tag = "pg_largeobject",
@@ -6419,11 +6419,11 @@ getTables(Archive *fout, int *numTables)
 		tblinfo[i].relreplident = *(PQgetvalue(res, i, i_relreplident));
 		tblinfo[i].rowsec = (strcmp(PQgetvalue(res, i, i_relrowsec), "t") == 0);
 		tblinfo[i].forcerowsec = (strcmp(PQgetvalue(res, i, i_relforcerowsec), "t") == 0);
-		tblinfo[i].frozenxid = atooid(PQgetvalue(res, i, i_relfrozenxid));
-		tblinfo[i].toast_frozenxid = atooid(PQgetvalue(res, i, i_toastfrozenxid));
+		tblinfo[i].frozenxid = strtou64(PQgetvalue(res, i, i_relfrozenxid), NULL, 0);
+		tblinfo[i].toast_frozenxid = strtou64(PQgetvalue(res, i, i_toastfrozenxid), NULL, 0);
 		tblinfo[i].toast_oid = atooid(PQgetvalue(res, i, i_toastoid));
-		tblinfo[i].minmxid = atooid(PQgetvalue(res, i, i_relminmxid));
-		tblinfo[i].toast_minmxid = atooid(PQgetvalue(res, i, i_toastminmxid));
+		tblinfo[i].minmxid = strtou64(PQgetvalue(res, i, i_relminmxid), NULL, 0);
+		tblinfo[i].toast_minmxid = strtou64(PQgetvalue(res, i, i_toastminmxid), NULL, 0);
 		tblinfo[i].reloptions = pg_strdup(PQgetvalue(res, i, i_reloptions));
 		if (PQgetisnull(res, i, i_checkoption))
 			tblinfo[i].checkoption = NULL;
diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h
index 1d21c2906f..bed20998ab 100644
--- a/src/bin/pg_dump/pg_dump.h
+++ b/src/bin/pg_dump/pg_dump.h
@@ -298,11 +298,11 @@ typedef struct _tableInfo
 	bool		rowsec;			/* is row security enabled? */
 	bool		forcerowsec;	/* is row security forced? */
 	bool		hasoids;		/* does it have OIDs? */
-	uint32		frozenxid;		/* table's relfrozenxid */
-	uint32		minmxid;		/* table's relminmxid */
+	uint64		frozenxid;		/* table's relfrozenxid */
+	uint64		minmxid;		/* table's relminmxid */
 	Oid			toast_oid;		/* toast table's OID, or 0 if none */
-	uint32		toast_frozenxid;	/* toast table's relfrozenxid, if any */
-	uint32		toast_minmxid;	/* toast table's relminmxid */
+	uint64		toast_frozenxid;	/* toast table's relfrozenxid, if any */
+	uint64		toast_minmxid;	/* toast table's relminmxid */
 	int			ncheck;			/* # of CHECK expressions */
 	Oid			reltype;		/* OID of table's composite type, if any */
 	Oid			reloftype;		/* underlying type for typed table */
diff --git a/src/bin/pg_resetwal/pg_resetwal.c b/src/bin/pg_resetwal/pg_resetwal.c
index 626f1608bc..73f733d096 100644
--- a/src/bin/pg_resetwal/pg_resetwal.c
+++ b/src/bin/pg_resetwal/pg_resetwal.c
@@ -63,7 +63,6 @@ static ControlFileData ControlFile; /* pg_control values */
 static XLogSegNo newXlogSegNo;	/* new XLOG segment # */
 static bool guessed = false;	/* T if we had to guess at any values */
 static const char *progname;
-static uint32 set_xid_epoch = (uint32) -1;
 static TransactionId set_oldest_xid = 0;
 static TransactionId set_xid = 0;
 static TransactionId set_oldest_commit_ts_xid = 0;
@@ -95,7 +94,6 @@ main(int argc, char *argv[])
 	static struct option long_options[] = {
 		{"commit-timestamp-ids", required_argument, NULL, 'c'},
 		{"pgdata", required_argument, NULL, 'D'},
-		{"epoch", required_argument, NULL, 'e'},
 		{"force", no_argument, NULL, 'f'},
 		{"next-wal-file", required_argument, NULL, 'l'},
 		{"multixact-ids", required_argument, NULL, 'm'},
@@ -137,7 +135,7 @@ main(int argc, char *argv[])
 	}
 
 
-	while ((c = getopt_long(argc, argv, "c:D:e:fl:m:no:O:u:x:", long_options, NULL)) != -1)
+	while ((c = getopt_long(argc, argv, "c:D:fl:m:no:O:u:x:", long_options, NULL)) != -1)
 	{
 		switch (c)
 		{
@@ -153,24 +151,9 @@ main(int argc, char *argv[])
 				noupdate = true;
 				break;
 
-			case 'e':
-				errno = 0;
-				set_xid_epoch = strtoul(optarg, &endptr, 0);
-				if (endptr == optarg || *endptr != '\0' || errno != 0)
-				{
-					/*------
-					  translator: the second %s is a command line argument (-e, etc) */
-					pg_log_error("invalid argument for option %s", "-e");
-					pg_log_error_hint("Try \"%s --help\" for more information.", progname);
-					exit(1);
-				}
-				if (set_xid_epoch == -1)
-					pg_fatal("transaction ID epoch (-e) must not be -1");
-				break;
-
 			case 'u':
 				errno = 0;
-				set_oldest_xid = strtoul(optarg, &endptr, 0);
+				set_oldest_xid = strtou64(optarg, &endptr, 0);
 				if (endptr == optarg || *endptr != '\0' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-u");
@@ -184,7 +167,7 @@ main(int argc, char *argv[])
 
 			case 'x':
 				errno = 0;
-				set_xid = strtoul(optarg, &endptr, 0);
+				set_xid = strtou64(optarg, &endptr, 0);
 				if (endptr == optarg || *endptr != '\0' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-x");
@@ -198,14 +181,14 @@ main(int argc, char *argv[])
 
 			case 'c':
 				errno = 0;
-				set_oldest_commit_ts_xid = strtoul(optarg, &endptr, 0);
+				set_oldest_commit_ts_xid = strtou64(optarg, &endptr, 0);
 				if (endptr == optarg || *endptr != ',' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-c");
 					pg_log_error_hint("Try \"%s --help\" for more information.", progname);
 					exit(1);
 				}
-				set_newest_commit_ts_xid = strtoul(endptr + 1, &endptr2, 0);
+				set_newest_commit_ts_xid = strtou64(endptr + 1, &endptr2, 0);
 				if (endptr2 == endptr + 1 || *endptr2 != '\0' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-c");
@@ -237,7 +220,7 @@ main(int argc, char *argv[])
 
 			case 'm':
 				errno = 0;
-				set_mxid = strtoul(optarg, &endptr, 0);
+				set_mxid = strtou64(optarg, &endptr, 0);
 				if (endptr == optarg || *endptr != ',' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-m");
@@ -245,7 +228,7 @@ main(int argc, char *argv[])
 					exit(1);
 				}
 
-				set_oldestmxid = strtoul(endptr + 1, &endptr2, 0);
+				set_oldestmxid = strtou64(endptr + 1, &endptr2, 0);
 				if (endptr2 == endptr + 1 || *endptr2 != '\0' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-m");
@@ -265,7 +248,7 @@ main(int argc, char *argv[])
 
 			case 'O':
 				errno = 0;
-				set_mxoff = strtoul(optarg, &endptr, 0);
+				set_mxoff = strtou64(optarg, &endptr, 0);
 				if (endptr == optarg || *endptr != '\0' || errno != 0)
 				{
 					pg_log_error("invalid argument for option %s", "-O");
@@ -408,11 +391,6 @@ main(int argc, char *argv[])
 	 * Adjust fields if required by switches.  (Do this now so that printout,
 	 * if any, includes these values.)
 	 */
-	if (set_xid_epoch != -1)
-		ControlFile.checkPointCopy.nextXid =
-			FullTransactionIdFromEpochAndXid(set_xid_epoch,
-											 XidFromFullTransactionId(ControlFile.checkPointCopy.nextXid));
-
 	if (set_oldest_xid != 0)
 	{
 		ControlFile.checkPointCopy.oldestXid = set_oldest_xid;
@@ -420,9 +398,7 @@ main(int argc, char *argv[])
 	}
 
 	if (set_xid != 0)
-		ControlFile.checkPointCopy.nextXid =
-			FullTransactionIdFromEpochAndXid(EpochFromFullTransactionId(ControlFile.checkPointCopy.nextXid),
-											 set_xid);
+		ControlFile.checkPointCopy.nextXid = FullTransactionIdFromXid(set_xid);
 
 	if (set_oldest_commit_ts_xid != 0)
 		ControlFile.checkPointCopy.oldestCommitTsXid = set_oldest_commit_ts_xid;
@@ -655,7 +631,7 @@ GuessControlValues(void)
 	ControlFile.checkPointCopy.PrevTimeLineID = 1;
 	ControlFile.checkPointCopy.fullPageWrites = false;
 	ControlFile.checkPointCopy.nextXid =
-		FullTransactionIdFromEpochAndXid(0, FirstNormalTransactionId);
+		FullTransactionIdFromXid(FirstNormalTransactionId);
 	ControlFile.checkPointCopy.nextOid = FirstGenbkiObjectId;
 	ControlFile.checkPointCopy.nextMulti = FirstMultiXactId;
 	ControlFile.checkPointCopy.nextMultiOffset = 0;
@@ -706,6 +682,8 @@ GuessControlValues(void)
  *
  * NB: this display should be just those fields that will not be
  * reset by RewriteControlFile().
+ *
+ * Special macros help to make translatable strings.
  */
 static void
 PrintControlValues(bool guessed)
@@ -725,8 +703,7 @@ PrintControlValues(bool guessed)
 		   ControlFile.checkPointCopy.ThisTimeLineID);
 	printf(_("Latest checkpoint's full_page_writes: %s\n"),
 		   ControlFile.checkPointCopy.fullPageWrites ? _("on") : _("off"));
-	printf(_("Latest checkpoint's NextXID:          %u:%llu\n"),
-		   EpochFromFullTransactionId(ControlFile.checkPointCopy.nextXid),
+	printf(_("Latest checkpoint's NextXID:          %llu\n"),
 		   (unsigned long long) XidFromFullTransactionId(ControlFile.checkPointCopy.nextXid));
 	printf(_("Latest checkpoint's NextOID:          %u\n"),
 		   ControlFile.checkPointCopy.nextOid);
@@ -824,12 +801,6 @@ PrintNewControlValues(void)
 			   ControlFile.checkPointCopy.oldestXidDB);
 	}
 
-	if (set_xid_epoch != -1)
-	{
-		printf(_("NextXID epoch:                        %u\n"),
-			   EpochFromFullTransactionId(ControlFile.checkPointCopy.nextXid));
-	}
-
 	if (set_oldest_commit_ts_xid != 0)
 	{
 		printf(_("oldestCommitTsXid:                    %llu\n"),
@@ -1140,7 +1111,6 @@ usage(void)
 			 "                                   set oldest and newest transactions bearing\n"
 			 "                                   commit timestamp (zero means no change)\n"));
 	printf(_(" [-D, --pgdata=]DATADIR            data directory\n"));
-	printf(_("  -e, --epoch=XIDEPOCH             set next transaction ID epoch\n"));
 	printf(_("  -f, --force                      force update to be done\n"));
 	printf(_("  -l, --next-wal-file=WALFILE      set minimum starting location for new WAL\n"));
 	printf(_("  -m, --multixact-ids=MXID,MXID    set next and oldest multitransaction ID\n"));
diff --git a/src/bin/pg_upgrade/Makefile b/src/bin/pg_upgrade/Makefile
index 7f8042f34a..1d47abd975 100644
--- a/src/bin/pg_upgrade/Makefile
+++ b/src/bin/pg_upgrade/Makefile
@@ -20,6 +20,7 @@ OBJS = \
 	parallel.o \
 	pg_upgrade.o \
 	relfilenumber.o \
+	segresize.o \
 	server.o \
 	tablespace.o \
 	util.o \
diff --git a/src/bin/pg_upgrade/check.c b/src/bin/pg_upgrade/check.c
index 69611bef4a..4cd7aae165 100644
--- a/src/bin/pg_upgrade/check.c
+++ b/src/bin/pg_upgrade/check.c
@@ -33,6 +33,7 @@ static void check_for_pg_role_prefix(ClusterInfo *cluster);
 static void check_for_new_tablespace_dir(ClusterInfo *new_cluster);
 static void check_for_user_defined_encoding_conversions(ClusterInfo *cluster);
 static char *get_canonical_locale_name(int category, const char *locale);
+static void check_for_32bit_xid_usage(ClusterInfo *cluster);
 
 
 /*
@@ -168,6 +169,17 @@ check_and_dump_old_cluster(bool live_check)
 	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 903)
 		old_9_3_check_for_line_data_type_usage(&old_cluster);
 
+	/* Prepare for 64bit xid */
+	if (old_cluster.controldata.cat_ver < XID_FORMATCHANGE_CAT_VER)
+	{
+		/* Check if 32-bit xid type is used in tables */
+		check_for_32bit_xid_usage(&old_cluster);
+		/* Check indexes to be upgraded */
+		invalidate_spgist_indexes(&old_cluster, true);
+		invalidate_gin_indexes(&old_cluster, true);
+		invalidate_external_indexes(&old_cluster, true);
+	}
+
 	/*
 	 * While not a check option, we do this now because this is the only time
 	 * the old server is running.
@@ -244,6 +256,17 @@ issue_warnings_and_set_wal_level(void)
 	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 906)
 		old_9_6_invalidate_hash_indexes(&new_cluster, false);
 
+	/* Raindex for 64bit xid */
+	if (old_cluster.controldata.cat_ver < XID_FORMATCHANGE_CAT_VER)
+	{
+		/* Check if 32-bit xid type is used in tables */
+		check_for_32bit_xid_usage(&old_cluster);
+		/* Check indexes to be upgraded */
+		invalidate_spgist_indexes(&old_cluster, true);
+		invalidate_gin_indexes(&old_cluster, true);
+		invalidate_external_indexes(&old_cluster, true);
+	}
+
 	report_extension_updates(&new_cluster);
 
 	stop_postmaster(false);
@@ -1516,3 +1539,94 @@ get_canonical_locale_name(int category, const char *locale)
 
 	return res;
 }
+
+/*
+ * check_for_32bit_xid_usage()
+ *
+ *	Postgres Pro Enterprise changes xid storage format to 64-bit.  Check if
+ *	xid type is used in tables.
+ */
+static void
+check_for_32bit_xid_usage(ClusterInfo *cluster)
+{
+	int			dbnum;
+	FILE	   *script = NULL;
+	bool		found = false;
+	char		output_path[MAXPGPATH];
+
+	prep_status("Checking for incompatible \"xid\" data type");
+
+	snprintf(output_path, sizeof(output_path), "tables_using_xid.txt");
+
+	for (dbnum = 0; dbnum < cluster->dbarr.ndbs; dbnum++)
+	{
+		PGresult   *res;
+		bool		db_used = false;
+		int			ntups;
+		int			rowno;
+		int			i_nspname,
+					i_relname,
+					i_attname;
+		DbInfo	   *active_db = &cluster->dbarr.dbs[dbnum];
+		PGconn	   *conn = connectToServer(cluster, active_db->db_name);
+
+		/*
+		 * While several relkinds don't store any data, e.g. views, they can
+		 * be used to define data types of other columns, so we check all
+		 * relkinds.
+		 */
+		res = executeQueryOrDie(conn,
+								"SELECT n.nspname, c.relname, a.attname "
+								"FROM	pg_catalog.pg_class c, "
+								"		pg_catalog.pg_namespace n, "
+								"		pg_catalog.pg_attribute a "
+								"WHERE	c.oid = a.attrelid AND "
+								"		a.attnum >= 1 AND "
+								"		a.atttypid = 'pg_catalog.xid'::pg_catalog.regtype AND "
+								"		c.relnamespace = n.oid AND "
+		/* exclude possible orphaned temp tables */
+								"		n.nspname !~ '^pg_temp_' AND "
+								"		n.nspname NOT IN ('pg_catalog', 'information_schema')");
+
+		ntups = PQntuples(res);
+		i_nspname = PQfnumber(res, "nspname");
+		i_relname = PQfnumber(res, "relname");
+		i_attname = PQfnumber(res, "attname");
+		for (rowno = 0; rowno < ntups; rowno++)
+		{
+			found = true;
+			if (script == NULL && (script = fopen_priv(output_path, "w")) == NULL)
+				pg_fatal("could not open file \"%s\": %s\n",
+						 output_path, strerror(errno));
+			if (!db_used)
+			{
+				fprintf(script, "Database: %s\n", active_db->db_name);
+				db_used = true;
+			}
+			fprintf(script, "  %s.%s.%s\n",
+					PQgetvalue(res, rowno, i_nspname),
+					PQgetvalue(res, rowno, i_relname),
+					PQgetvalue(res, rowno, i_attname));
+		}
+
+		PQclear(res);
+
+		PQfinish(conn);
+	}
+
+	if (script)
+		fclose(script);
+
+	if (found)
+	{
+		pg_log(PG_REPORT, "fatal\n");
+		pg_fatal("Your installation contains the \"xid\" data type in user tables.\n"
+				 "The internal format of \"xid\" changed in Postgres Pro Enterprise so this cluster\n"
+				 "cannot currently be upgraded.  Note that even dropped attributes cause a problem.\n"
+				 "You can remove the problem tables and restart the upgrade.\n"
+				 "A list of the problem columns is in the file:\n"
+				 "    %s\n\n", output_path);
+	}
+	else
+		check_ok();
+}
diff --git a/src/bin/pg_upgrade/controldata.c b/src/bin/pg_upgrade/controldata.c
index 2b1b1a3435..8ee1ba4618 100644
--- a/src/bin/pg_upgrade/controldata.c
+++ b/src/bin/pg_upgrade/controldata.c
@@ -282,6 +282,8 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 			xid.value = strtou64(p, NULL, 10);
 
 			/*
+			 * Try to read 32-bit XID format 'epoch:xid'.
+			 *
 			 * Delimiter changed from '/' to ':' in 9.6.  We don't test for
 			 * the catalog version of the change because the catalog version
 			 * is pulled from pg_controldata too, and it isn't worth adding an
@@ -297,8 +299,7 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 			if (p == NULL)
 			{
 				/* FullTransactionId representation */
-				cluster->controldata.chkpnt_nxtxid = XidFromFullTransactionId(xid);
-				cluster->controldata.chkpnt_nxtepoch = EpochFromFullTransactionId(xid);
+				cluster->controldata.chkpnt_nxtxid = xid.value;
 			}
 			else
 			{
@@ -307,8 +308,8 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 
 				/* Epoch:Xid representation */
 				p++;				/* remove '/' or ':' char */
-				cluster->controldata.chkpnt_nxtxid = str2uint(p);
-				cluster->controldata.chkpnt_nxtepoch = (TransactionId) XidFromFullTransactionId(xid);
+				cluster->controldata.chkpnt_nxtxid = (XidFromFullTransactionId(xid)) << 32 |
+													  (TransactionId) str2uint(p);
 			}
 
 			got_xid = true;
@@ -332,7 +333,7 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
 
 			p++;				/* remove ':' char */
-			cluster->controldata.chkpnt_nxtmulti = str2uint(p);
+			cluster->controldata.chkpnt_nxtmulti = strtou64(p, NULL, 10);
 			got_multi = true;
 		}
 		else if ((p = strstr(bufin, "Latest checkpoint's oldestXID:")) != NULL)
@@ -343,7 +344,7 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
 
 			p++;				/* remove ':' char */
-			cluster->controldata.chkpnt_oldstxid = str2uint(p);
+			cluster->controldata.chkpnt_oldstxid = strtou64(p, NULL, 10);
 			got_oldestxid = true;
 		}
 		else if ((p = strstr(bufin, "Latest checkpoint's oldestMultiXid:")) != NULL)
@@ -354,7 +355,7 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
 
 			p++;				/* remove ':' char */
-			cluster->controldata.chkpnt_oldstMulti = str2uint(p);
+			cluster->controldata.chkpnt_oldstMulti = strtou64(p, NULL, 10);
 			got_oldestmulti = true;
 		}
 		else if ((p = strstr(bufin, "Latest checkpoint's NextMultiOffset:")) != NULL)
@@ -365,7 +366,7 @@ get_control_data(ClusterInfo *cluster, bool live_check)
 				pg_fatal("%d: controldata retrieval problem\n", __LINE__);
 
 			p++;				/* remove ':' char */
-			cluster->controldata.chkpnt_nxtmxoff = str2uint(p);
+			cluster->controldata.chkpnt_nxtmxoff = strtou64(p, NULL, 10);
 			got_mxoff = true;
 		}
 		else if ((p = strstr(bufin, "First log segment after reset:")) != NULL)
diff --git a/src/bin/pg_upgrade/file.c b/src/bin/pg_upgrade/file.c
index b84868c751..4daacdd721 100644
--- a/src/bin/pg_upgrade/file.c
+++ b/src/bin/pg_upgrade/file.c
@@ -25,6 +25,7 @@
 #include "storage/bufpage.h"
 #include "storage/checksum.h"
 #include "storage/checksum_impl.h"
+#include "storage/fsm_internals.h"
 
 
 /*
@@ -152,6 +153,112 @@ linkFile(const char *src, const char *dst,
 				 schemaName, relName, src, dst, strerror(errno));
 }
 
+/* Context for file rewriting */
+typedef struct FileRewriteContext
+{
+	const char *fromfile;
+	const char *tofile;
+	const char *schemaName;
+	const char *relName;
+	int			src_fd;
+	int			dst_fd;
+	ssize_t		src_filesize;
+	ssize_t		totalBytesRead;
+	BlockNumber last_blkno;
+	bool		old_lastblk;
+}			FileRewriteContext;
+
+/* Initialize context for file rewriting */
+static void
+rewriteFileInit(FileRewriteContext * cxt,
+				const char *fromfile, const char *tofile,
+				const char *schemaName, const char *relName)
+{
+	struct stat statbuf;
+
+	cxt->fromfile = fromfile;
+	cxt->tofile = tofile;
+	cxt->schemaName = schemaName;
+	cxt->relName = relName;
+	cxt->totalBytesRead = 0;
+	cxt->last_blkno = InvalidBlockNumber;
+	cxt->old_lastblk = false;
+
+	/* Open old and new files */
+	if ((cxt->src_fd = open(fromfile, O_RDONLY | PG_BINARY, 0)) < 0)
+		pg_fatal("error while copying relation \"%s.%s\": could not open file \"%s\": %s\n",
+				 schemaName, relName, fromfile, strerror(errno));
+
+	if (fstat(cxt->src_fd, &statbuf) != 0)
+		pg_fatal("error while copying relation \"%s.%s\": could not stat file \"%s\": %s\n",
+				 schemaName, relName, fromfile, strerror(errno));
+
+	if ((cxt->dst_fd = open(tofile, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
+							pg_file_create_mode)) < 0)
+		pg_fatal("error while copying relation \"%s.%s\": could not create file \"%s\": %s\n",
+				 schemaName, relName, tofile, strerror(errno));
+
+	/* Save old file size */
+	cxt->src_filesize = statbuf.st_size;
+}
+
+/* Clean up file rewriting context */
+static void
+rewriteFileCleanup(FileRewriteContext * cxt)
+{
+	close(cxt->dst_fd);
+	close(cxt->src_fd);
+}
+
+/* Read old page of the rewritten file */
+static ssize_t
+rewriteFileReadPage(FileRewriteContext * cxt, Page page)
+{
+	ssize_t		bytesRead;
+
+	if (cxt->totalBytesRead >= cxt->src_filesize)
+		return 0;
+
+	if ((bytesRead = read(cxt->src_fd, page, BLCKSZ)) != BLCKSZ)
+	{
+		if (bytesRead < 0)
+			pg_fatal("error while copying relation \"%s.%s\": could not read file \"%s\": %s\n",
+					 cxt->schemaName, cxt->relName, cxt->fromfile, strerror(errno));
+		else
+			pg_fatal("error while copying relation \"%s.%s\": partial page found in file \"%s\"\n",
+					 cxt->schemaName, cxt->relName, cxt->fromfile);
+	}
+
+	cxt->totalBytesRead += BLCKSZ;
+	cxt->old_lastblk = (cxt->totalBytesRead == cxt->src_filesize);
+
+	return bytesRead;
+}
+
+/* Write new page of the rewritten file */
+static void
+rewriteFileWritePage(FileRewriteContext * cxt, Page page, BlockNumber blkno)
+{
+	/* Set new checksum for page, if enabled */
+	if (new_cluster.controldata.data_checksum_version != 0)
+		((PageHeader) page)->pd_checksum = pg_checksum_page(page, blkno);
+
+	/* Write page */
+	errno = 0;
+
+	if ((blkno != (cxt->last_blkno == InvalidBlockNumber ? 0 : cxt->last_blkno + 1) &&
+		 lseek(cxt->dst_fd, (off_t) BLCKSZ * blkno, SEEK_SET) != (off_t) BLCKSZ * blkno) ||
+		write(cxt->dst_fd, page, BLCKSZ) != BLCKSZ)
+	{
+		/* if write didn't set errno, assume problem is no disk space */
+		if (errno == 0)
+			errno = ENOSPC;
+		pg_fatal("error while copying relation \"%s.%s\": could not write file \"%s\": %s\n",
+				 cxt->schemaName, cxt->relName, cxt->tofile, strerror(errno));
+	}
+
+	cxt->last_blkno = blkno;
+}
 
 /*
  * rewriteVisibilityMap()
@@ -173,34 +280,17 @@ void
 rewriteVisibilityMap(const char *fromfile, const char *tofile,
 					 const char *schemaName, const char *relName)
 {
-	int			src_fd;
-	int			dst_fd;
+	FileRewriteContext cxt;
 	PGAlignedBlock buffer;
 	PGAlignedBlock new_vmbuf;
-	ssize_t		totalBytesRead = 0;
-	ssize_t		src_filesize;
 	int			rewriteVmBytesPerPage;
 	BlockNumber new_blkno = 0;
-	struct stat statbuf;
+	ssize_t		bytesRead;
 
 	/* Compute number of old-format bytes per new page */
 	rewriteVmBytesPerPage = (BLCKSZ - SizeOfPageHeaderData) / 2;
 
-	if ((src_fd = open(fromfile, O_RDONLY | PG_BINARY, 0)) < 0)
-		pg_fatal("error while copying relation \"%s.%s\": could not open file \"%s\": %s\n",
-				 schemaName, relName, fromfile, strerror(errno));
-
-	if (fstat(src_fd, &statbuf) != 0)
-		pg_fatal("error while copying relation \"%s.%s\": could not stat file \"%s\": %s\n",
-				 schemaName, relName, fromfile, strerror(errno));
-
-	if ((dst_fd = open(tofile, O_RDWR | O_CREAT | O_EXCL | PG_BINARY,
-					   pg_file_create_mode)) < 0)
-		pg_fatal("error while copying relation \"%s.%s\": could not create file \"%s\": %s\n",
-				 schemaName, relName, tofile, strerror(errno));
-
-	/* Save old file size */
-	src_filesize = statbuf.st_size;
+	rewriteFileInit(&cxt, fromfile, tofile, schemaName, relName);
 
 	/*
 	 * Turn each visibility map page into 2 pages one by one. Each new page
@@ -208,27 +298,12 @@ rewriteVisibilityMap(const char *fromfile, const char *tofile,
 	 * last page is empty, we skip it, mostly to avoid turning one-page
 	 * visibility maps for small relations into two pages needlessly.
 	 */
-	while (totalBytesRead < src_filesize)
+	while ((bytesRead = rewriteFileReadPage(&cxt, buffer.data)) > 0)
 	{
-		ssize_t		bytesRead;
 		char	   *old_cur;
 		char	   *old_break;
 		char	   *old_blkend;
 		PageHeaderData pageheader;
-		bool		old_lastblk;
-
-		if ((bytesRead = read(src_fd, buffer.data, BLCKSZ)) != BLCKSZ)
-		{
-			if (bytesRead < 0)
-				pg_fatal("error while copying relation \"%s.%s\": could not read file \"%s\": %s\n",
-						 schemaName, relName, fromfile, strerror(errno));
-			else
-				pg_fatal("error while copying relation \"%s.%s\": partial page found in file \"%s\"\n",
-						 schemaName, relName, fromfile);
-		}
-
-		totalBytesRead += BLCKSZ;
-		old_lastblk = (totalBytesRead == src_filesize);
 
 		/* Save the page header data */
 		memcpy(&pageheader, buffer.data, SizeOfPageHeaderData);
@@ -253,7 +328,7 @@ rewriteVisibilityMap(const char *fromfile, const char *tofile,
 			memcpy(new_vmbuf.data, &pageheader, SizeOfPageHeaderData);
 
 			/* Rewriting the last part of the last old page? */
-			old_lastpart = old_lastblk && (old_break == old_blkend);
+			old_lastpart = cxt.old_lastblk && (old_break == old_blkend);
 
 			new_cur = new_vmbuf.data + SizeOfPageHeaderData;
 
@@ -287,20 +362,7 @@ rewriteVisibilityMap(const char *fromfile, const char *tofile,
 			if (old_lastpart && empty)
 				break;
 
-			/* Set new checksum for visibility map page, if enabled */
-			if (new_cluster.controldata.data_checksum_version != 0)
-				((PageHeader) new_vmbuf.data)->pd_checksum =
-					pg_checksum_page(new_vmbuf.data, new_blkno);
-
-			errno = 0;
-			if (write(dst_fd, new_vmbuf.data, BLCKSZ) != BLCKSZ)
-			{
-				/* if write didn't set errno, assume problem is no disk space */
-				if (errno == 0)
-					errno = ENOSPC;
-				pg_fatal("error while copying relation \"%s.%s\": could not write file \"%s\": %s\n",
-						 schemaName, relName, tofile, strerror(errno));
-			}
+			rewriteFileWritePage(&cxt, new_vmbuf.data, new_blkno);
 
 			/* Advance for next new page */
 			old_break += rewriteVmBytesPerPage;
@@ -308,9 +370,7 @@ rewriteVisibilityMap(const char *fromfile, const char *tofile,
 		}
 	}
 
-	/* Clean up */
-	close(dst_fd);
-	close(src_fd);
+	rewriteFileCleanup(&cxt);
 }
 
 void
diff --git a/src/bin/pg_upgrade/pg_upgrade.c b/src/bin/pg_upgrade/pg_upgrade.c
index d2b519132f..9414800438 100644
--- a/src/bin/pg_upgrade/pg_upgrade.c
+++ b/src/bin/pg_upgrade/pg_upgrade.c
@@ -44,6 +44,9 @@
 #include <langinfo.h>
 #endif
 
+#include "access/multixact.h"
+#include "access/transam.h"
+#include "access/xlog_internal.h"
 #include "catalog/pg_class_d.h"
 #include "common/file_perm.h"
 #include "common/logging.h"
@@ -58,6 +61,7 @@ static void copy_xact_xlog_xid(void);
 static void set_frozenxids(bool minmxid_only);
 static void make_outputdirs(char *pgdata);
 static void setup(char *argv0, bool *live_check);
+static bool is_xid_wraparound(ClusterInfo *cluster);
 
 ClusterInfo old_cluster,
 			new_cluster;
@@ -361,7 +365,6 @@ setup(char *argv0, bool *live_check)
 	}
 }
 
-
 static void
 prepare_new_cluster(void)
 {
@@ -507,16 +510,58 @@ create_new_objects(void)
 	check_ok();
 
 	/*
-	 * We don't have minmxids for databases or relations in pre-9.3 clusters,
-	 * so set those after we have restored the schema.
+	 * Refix datfrozenxid and datminmxid
 	 */
 	if (GET_MAJOR_VERSION(old_cluster.major_version) <= 902)
 		set_frozenxids(true);
+	else if (old_cluster.controldata.cat_ver < XID_FORMATCHANGE_CAT_VER &&
+			 new_cluster.controldata.cat_ver >= XID_FORMATCHANGE_CAT_VER)
+	{
+		/*
+		 * During upgrade from 32-bit to 64-bit xids save relfrozenxids if
+		 * there was no wraparound in old cluster. Otherwise, reset them to
+		 * FirstNormalTransactionId value.
+		 */
+		if (is_xid_wraparound(&old_cluster))
+			set_frozenxids(false);
+		else
+			set_frozenxids(true);
+	}
 
 	/* update new_cluster info now that we have objects in the databases */
 	get_db_and_rel_infos(&new_cluster);
 }
 
+/*
+ * is_xid_wraparound()
+ *
+ * Return true if 32-xid cluster had wraparound.
+ */
+static bool
+is_xid_wraparound(ClusterInfo *cluster)
+{
+	PGconn	   *conn;
+	PGresult   *res;
+	bool		is_wraparound;
+
+	conn = connectToServer(cluster, "template1");
+
+	/*
+	 * txid_current is extended with an "epoch" counter, so to check
+	 * wraparound in old 32-xid cluster we cut epoch by casting to int4.
+	 */
+	res = executeQueryOrDie(conn,
+							"SELECT 1 "
+							"FROM   pg_catalog.pg_database, txid_current() tx "
+							"WHERE  (tx %% 4294967295)::bigint <= datfrozenxid::text::bigint "
+							"LIMIT  1");
+	is_wraparound = PQntuples(res) ? true : false;
+	PQclear(res);
+	PQfinish(conn);
+
+	return is_wraparound;
+}
+
 /*
  * Delete the given subdirectory contents from the new cluster
  */
@@ -565,14 +610,37 @@ copy_subdir_files(const char *old_subdir, const char *new_subdir)
 static void
 copy_xact_xlog_xid(void)
 {
-	/*
-	 * Copy old commit logs to new data dir. pg_clog has been renamed to
-	 * pg_xact in post-10 clusters.
-	 */
-	copy_subdir_files(GET_MAJOR_VERSION(old_cluster.major_version) <= 906 ?
-					  "pg_clog" : "pg_xact",
-					  GET_MAJOR_VERSION(new_cluster.major_version) <= 906 ?
-					  "pg_clog" : "pg_xact");
+	TransactionId next_xid;
+
+#define GetClogDirName(cluster) \
+	GET_MAJOR_VERSION(cluster.major_version) <= 906 ? "pg_clog" : "pg_xact"
+
+	/* Set next xid to 2^32 if we're upgrading from 32 bit postgres */
+	if (old_cluster.controldata.cat_ver < XID_FORMATCHANGE_CAT_VER &&
+		new_cluster.controldata.cat_ver >= XID_FORMATCHANGE_CAT_VER)
+		next_xid = ((TransactionId) 1 << 32);
+	else
+		next_xid = old_cluster.controldata.chkpnt_nxtxid;
+
+	if (old_cluster.controldata.cat_ver < XID_FORMATCHANGE_CAT_VER &&
+		new_cluster.controldata.cat_ver >= XID_FORMATCHANGE_CAT_VER)
+	{
+		/* Convert commit logs and copy to the new data dir */
+		prep_status("Transforming commit log segments");
+		convert_xact(psprintf("%s/%s", old_cluster.pgdata, GetClogDirName(old_cluster)),
+					 psprintf("%s/%s", new_cluster.pgdata, GetClogDirName(new_cluster)));
+		check_ok();
+	}
+	else
+	{
+		/*
+		 * Copy old commit logs to new data dir. pg_clog has been renamed to
+		 * pg_xact in post-10 clusters.
+		 */
+		prep_status("Copying commit log segments");
+		copy_subdir_files(GetClogDirName(old_cluster), GetClogDirName(new_cluster));
+		check_ok();
+	}
 
 	prep_status("Setting oldest XID for new cluster");
 	exec_prog(UTILITY_LOG_FILE, NULL, true, true,
@@ -586,19 +654,20 @@ copy_xact_xlog_xid(void)
 	prep_status("Setting next transaction ID and epoch for new cluster");
 	exec_prog(UTILITY_LOG_FILE, NULL, true, true,
 			  "\"%s/pg_resetwal\" -f -x %llu \"%s\"",
-			  new_cluster.bindir,
-			  (unsigned long long) old_cluster.controldata.chkpnt_nxtxid,
+			  new_cluster.bindir, (unsigned long long) next_xid,
 			  new_cluster.pgdata);
+#ifdef NOT_USED
 	exec_prog(UTILITY_LOG_FILE, NULL, true, true,
 			  "\"%s/pg_resetwal\" -f -e %u \"%s\"",
 			  new_cluster.bindir, old_cluster.controldata.chkpnt_nxtepoch,
 			  new_cluster.pgdata);
+#endif
 	/* must reset commit timestamp limits also */
 	exec_prog(UTILITY_LOG_FILE, NULL, true, true,
 			  "\"%s/pg_resetwal\" -f -c %llu,%llu \"%s\"",
 			  new_cluster.bindir,
-			  (unsigned long long) old_cluster.controldata.chkpnt_nxtxid,
-			  (unsigned long long) old_cluster.controldata.chkpnt_nxtxid,
+			  (unsigned long long) next_xid,
+			  (unsigned long long) next_xid,
 			  new_cluster.pgdata);
 	check_ok();
 
@@ -611,8 +680,48 @@ copy_xact_xlog_xid(void)
 	if (old_cluster.controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER &&
 		new_cluster.controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER)
 	{
-		copy_subdir_files("pg_multixact/offsets", "pg_multixact/offsets");
-		copy_subdir_files("pg_multixact/members", "pg_multixact/members");
+		uint64		oldest_mxid = old_cluster.controldata.chkpnt_oldstMulti;
+		uint64		next_mxid = old_cluster.controldata.chkpnt_nxtmulti;
+		uint64		next_mxoff = old_cluster.controldata.chkpnt_nxtmxoff;
+
+		if (old_cluster.controldata.cat_ver >= XID_FORMATCHANGE_CAT_VER)
+		{
+			copy_subdir_files("pg_multixact/offsets", "pg_multixact/offsets");
+			copy_subdir_files("pg_multixact/members", "pg_multixact/members");
+		}
+		else
+		{
+			MultiXactOffset oldest_mxoff;
+
+			remove_new_subdir("pg_multixact/offsets", false);
+			oldest_mxoff = convert_multixact_offsets("pg_multixact/offsets", "pg_multixact/offsets");
+
+			remove_new_subdir("pg_multixact/members", false);
+			convert_multixact_members("pg_multixact/members", "pg_multixact/members", oldest_mxoff);
+
+			/*
+			 * Handle wraparound if we're upgrading from 32 bit postgres.
+			 * Invalid 0 mxids/offsets are skipped, so 1 becomes 2^32.
+			 */
+			if (oldest_mxoff)
+			{
+				if (next_mxid < oldest_mxid)
+					next_mxid += ((MultiXactId) 1 << 32) - FirstMultiXactId;
+
+				if (next_mxoff < oldest_mxoff)
+					next_mxoff += ((MultiXactOffset) 1 << 32) - 1;
+
+				/* Offsets and members were rewritten, oldest_mxoff = 1 */
+				next_mxoff -= oldest_mxoff - 1;
+				oldest_mxoff = 1;
+
+				/*
+				 * Save converted next_mxid for possible usage in
+				 * set_frozenxids()
+				 */
+				old_cluster.controldata.chkpnt_nxtmulti = next_mxid;
+			}
+		}
 
 		prep_status("Setting next multixact ID and offset for new cluster");
 
@@ -623,9 +732,9 @@ copy_xact_xlog_xid(void)
 		exec_prog(UTILITY_LOG_FILE, NULL, true, true,
 				  "\"%s/pg_resetwal\" -O %llu -m %llu,%llu \"%s\"",
 				  new_cluster.bindir,
-				  (unsigned long long) old_cluster.controldata.chkpnt_nxtmxoff,
-				  (unsigned long long) old_cluster.controldata.chkpnt_nxtmulti,
-				  (unsigned long long) old_cluster.controldata.chkpnt_oldstMulti,
+				  (unsigned long long) next_mxoff,
+				  (unsigned long long) next_mxid,
+				  (unsigned long long) oldest_mxid,
 				  new_cluster.pgdata);
 		check_ok();
 	}
@@ -699,6 +808,8 @@ set_frozenxids(bool minmxid_only)
 	int			ntups;
 	int			i_datname;
 	int			i_datallowconn;
+	TransactionId frozen_xid;
+	MultiXactId minmxid;
 
 	if (!minmxid_only)
 		prep_status("Setting frozenxid and minmxid counters in new cluster");
@@ -707,18 +818,26 @@ set_frozenxids(bool minmxid_only)
 
 	conn_template1 = connectToServer(&new_cluster, "template1");
 
+	if (old_cluster.controldata.cat_ver < XID_FORMATCHANGE_CAT_VER &&
+		new_cluster.controldata.cat_ver >= XID_FORMATCHANGE_CAT_VER)
+		frozen_xid = FirstNormalTransactionId;
+	else
+		frozen_xid = old_cluster.controldata.chkpnt_nxtxid;
+
+	minmxid = old_cluster.controldata.chkpnt_nxtmulti;
+
 	if (!minmxid_only)
 		/* set pg_database.datfrozenxid */
 		PQclear(executeQueryOrDie(conn_template1,
 								  "UPDATE pg_catalog.pg_database "
 								  "SET	datfrozenxid = '%llu'",
-								  (unsigned long long) old_cluster.controldata.chkpnt_nxtxid));
+								  (unsigned long long) frozen_xid));
 
 	/* set pg_database.datminmxid */
 	PQclear(executeQueryOrDie(conn_template1,
 							  "UPDATE pg_catalog.pg_database "
 							  "SET	datminmxid = '%llu'",
-							  (unsigned long long) old_cluster.controldata.chkpnt_nxtmulti));
+							  (unsigned long long) minmxid));
 
 	/* get database names */
 	dbres = executeQueryOrDie(conn_template1,
@@ -758,7 +877,7 @@ set_frozenxids(bool minmxid_only)
 									  CppAsString2(RELKIND_RELATION) ", "
 									  CppAsString2(RELKIND_MATVIEW) ", "
 									  CppAsString2(RELKIND_TOASTVALUE) ")",
-									  (unsigned long long) old_cluster.controldata.chkpnt_nxtxid));
+									  (unsigned long long) frozen_xid));
 
 		/* set pg_class.relminmxid */
 		PQclear(executeQueryOrDie(conn,
@@ -769,7 +888,7 @@ set_frozenxids(bool minmxid_only)
 								  CppAsString2(RELKIND_RELATION) ", "
 								  CppAsString2(RELKIND_MATVIEW) ", "
 								  CppAsString2(RELKIND_TOASTVALUE) ")",
-								  (unsigned long long) old_cluster.controldata.chkpnt_nxtmulti));
+								  (unsigned long long) minmxid));
 		PQfinish(conn);
 
 		/* Reset datallowconn flag */
diff --git a/src/bin/pg_upgrade/pg_upgrade.h b/src/bin/pg_upgrade/pg_upgrade.h
index 50dfe9e81c..bffe229c3b 100644
--- a/src/bin/pg_upgrade/pg_upgrade.h
+++ b/src/bin/pg_upgrade/pg_upgrade.h
@@ -114,6 +114,11 @@ extern char *output_files[];
  */
 #define MULTIXACT_FORMATCHANGE_CAT_VER 201301231
 
+/*
+ * xid format changed from 32-bit to 64-bit.
+ */
+#define XID_FORMATCHANGE_CAT_VER 999999999
+
 /*
  * large object chunk size added to pg_controldata,
  * commit 5f93c37805e7485488480916b4585e098d3cc883
@@ -198,13 +203,13 @@ typedef struct
 	uint32		ctrl_ver;
 	uint32		cat_ver;
 	char		nextxlogfile[25];
-	uint32		chkpnt_nxtxid;
-	uint32		chkpnt_nxtepoch;
+	uint64		chkpnt_nxtxid;
+	uint32		chkpnt_nxtepoch;	/* for 32bit xids only */
 	uint32		chkpnt_nxtoid;
-	uint32		chkpnt_nxtmulti;
-	uint32		chkpnt_nxtmxoff;
-	uint32		chkpnt_oldstMulti;
-	uint32		chkpnt_oldstxid;
+	uint64		chkpnt_nxtmulti;
+	uint64		chkpnt_nxtmxoff;
+	uint64		chkpnt_oldstMulti;
+	uint64		chkpnt_oldstxid;
 	uint32		align;
 	uint32		blocksz;
 	uint32		largesz;
@@ -457,6 +462,10 @@ void		old_9_6_invalidate_hash_indexes(ClusterInfo *cluster,
 void		old_11_check_for_sql_identifier_data_type_usage(ClusterInfo *cluster);
 void		report_extension_updates(ClusterInfo *cluster);
 
+void		invalidate_spgist_indexes(ClusterInfo *cluster, bool check_mode);
+void		invalidate_gin_indexes(ClusterInfo *cluster, bool check_mode);
+void		invalidate_external_indexes(ClusterInfo *cluster, bool check_mode);
+
 /* parallel.c */
 void		parallel_exec_prog(const char *log_file, const char *opt_log_file,
 							   const char *fmt,...) pg_attribute_printf(3, 4);
@@ -464,3 +473,9 @@ void		parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr
 										  char *old_pgdata, char *new_pgdata,
 										  char *old_tablespace);
 bool		reap_child(bool wait_for_child);
+
+/* segresize.c */
+void		convert_xact(const char *olddir, const char *newdir);
+MultiXactOffset convert_multixact_offsets(const char *olddir, const char *newdir);
+void		convert_multixact_members(const char *olddir, const char *newdir,
+									  MultiXactOffset oldest_mxoff);
diff --git a/src/bin/pg_upgrade/segresize.c b/src/bin/pg_upgrade/segresize.c
new file mode 100644
index 0000000000..99e2c5ecde
--- /dev/null
+++ b/src/bin/pg_upgrade/segresize.c
@@ -0,0 +1,586 @@
+/*-------------------------------------------------------------------------
+ *
+ * segresize.c
+ *	  SLRU segment resize utility from 32bit to 64bit xid format
+ *
+ * Copyright (c) 2015-2022, Postgres Professional
+ *
+ * IDENTIFICATION
+ *	  src/bin/pg_upgrade/segresize.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres_fe.h"
+
+#include "pg_upgrade.h"
+#include "access/multixact.h"
+#include "access/transam.h"
+
+#define SLRU_PAGES_PER_SEGMENT_OLD	32
+#define SLRU_PAGES_PER_SEGMENT		32 /* Should be equal to value from slru.h */
+
+#define CLOG_BITS_PER_XACT		2
+#define CLOG_XACTS_PER_BYTE		4
+#define CLOG_XACTS_PER_PAGE		(BLCKSZ * CLOG_XACTS_PER_BYTE)
+
+typedef uint32 MultiXactId32;
+typedef uint32 MultiXactOffset32;
+typedef uint32 TransactionId32;
+
+#define MaxTransactionId32					((TransactionId32) 0xFFFFFFFF)
+#define MaxMultiXactId32					((MultiXactId32) 0xFFFFFFFF)
+#define MaxMultiXactOffset32				((MultiXactOffset32) 0xFFFFFFFF)
+
+#define MULTIXACT_OFFSETS_PER_PAGE_OLD		(BLCKSZ / sizeof(MultiXactOffset32))
+#define MULTIXACT_OFFSETS_PER_PAGE			(BLCKSZ / sizeof(MultiXactOffset))
+
+#define MXACT_MEMBER_FLAGS_PER_BYTE			1
+
+/* 64xid */
+#define MULTIXACT_FLAGBYTES_PER_GROUP		8
+#define MULTIXACT_MEMBERS_PER_MEMBERGROUP	\
+	(MULTIXACT_FLAGBYTES_PER_GROUP * MXACT_MEMBER_FLAGS_PER_BYTE)
+/* size in bytes of a complete group */
+#define MULTIXACT_MEMBERGROUP_SIZE \
+	(sizeof(TransactionId) * MULTIXACT_MEMBERS_PER_MEMBERGROUP + MULTIXACT_FLAGBYTES_PER_GROUP)
+#define MULTIXACT_MEMBERGROUPS_PER_PAGE (BLCKSZ / MULTIXACT_MEMBERGROUP_SIZE)
+
+/* 32xid */
+#define MULTIXACT_FLAGBYTES_PER_GROUP_OLD	4
+#define MULTIXACT_MEMBERS_PER_MEMBERGROUP_OLD	\
+	(MULTIXACT_FLAGBYTES_PER_GROUP_OLD * MXACT_MEMBER_FLAGS_PER_BYTE)
+/* size in bytes of a complete group */
+#define MULTIXACT_MEMBERGROUP_SIZE_OLD \
+	(sizeof(TransactionId32) * MULTIXACT_MEMBERS_PER_MEMBERGROUP_OLD + MULTIXACT_FLAGBYTES_PER_GROUP_OLD)
+#define MULTIXACT_MEMBERGROUPS_PER_PAGE_OLD (BLCKSZ / MULTIXACT_MEMBERGROUP_SIZE_OLD)
+#define MULTIXACT_MEMBERS_PER_PAGE_OLD	\
+	(MULTIXACT_MEMBERGROUPS_PER_PAGE_OLD * MULTIXACT_MEMBERS_PER_MEMBERGROUP_OLD)
+
+typedef struct SLRUSegmentState
+{
+	const char	   *dir;
+	FILE		   *file;
+	int64			segno;
+	int64			pageno;
+	bool			is_empty_segment;
+}			SLRUSegmentState;
+
+static char *
+slru_filename_old(const char *path, int64 segno)
+{
+	Assert(segno <= PG_INT32_MAX);
+	return psprintf("%s/%04X", path, (int) segno);
+}
+
+static char *
+slru_filename_new(const char *path, int64 segno)
+{
+	return psprintf("%s/%012llX", path, (long long) segno);
+}
+
+static inline FILE *
+open_file(SLRUSegmentState *state,
+		  char * (filename_fn)(const char *path, int64 segno),
+		  char *mode, char *fatal_msg)
+{
+	char	*filename = filename_fn(state->dir, state->segno);
+	FILE	*fd = fopen(filename, mode);
+
+	if (!fd)
+		pg_fatal(fatal_msg, filename);
+
+	pfree(filename);
+
+	return fd;
+}
+
+static void
+close_file(SLRUSegmentState *state,
+		   char * (filename_fn)(const char *path, int64 segno))
+{
+	if (state->file != NULL)
+	{
+		if (fclose(state->file) != 0)
+			pg_fatal("could not close file \"%s\": %m",
+					 filename_fn(state->dir, state->segno));
+		state->file = NULL;
+	}
+}
+
+static inline int
+read_file(SLRUSegmentState *state, void *buf)
+{
+	size_t		n = fread(buf, sizeof(char), BLCKSZ, state->file);
+
+	if (n != 0)
+		return n;
+
+	if (ferror(state->file))
+		pg_fatal("could not read file \"%s\": %m",
+				 slru_filename_old(state->dir, state->segno));
+
+	if (!feof(state->file))
+		pg_fatal("unknown file read state \"%s\": %m",
+				 slru_filename_old(state->dir, state->segno));
+
+	close_file(state, slru_filename_old);
+
+	return 0;
+}
+
+static int
+read_old_segment_page(SLRUSegmentState *state, void *buf, bool *is_empty)
+{
+	int		n;
+
+	/* Open next segment file, if needed */
+	if (!state->file)
+	{
+		state->file = open_file(state, slru_filename_old, "rb",
+								"could not open source file \"%s\": %m");
+
+		/* Set position to the needed page */
+		if (fseek(state->file, state->pageno * BLCKSZ, SEEK_SET))
+			close_file(state, slru_filename_old);
+
+		/*
+		 * Skip segment conversion if segment file doesn't exist.
+		 * First segment file should exist in any case.
+		 */
+		if (state->segno != 0)
+			state->is_empty_segment = true;
+	}
+
+	if (state->file)
+	{
+		/* Segment file does exist, read page from it */
+		state->is_empty_segment = false;
+
+		/* Try to read BLCKSZ bytes */
+		n = read_file(state, buf);
+		*is_empty = (n == 0);
+
+		/* Zeroing buf tail if needed */
+		if (n)
+			memset((char *) buf + n, 0, BLCKSZ - n);
+	}
+	else
+	{
+		n = state->is_empty_segment ?
+				BLCKSZ :	/* Skip empty block at the end of segment */
+				0;			/* We reached the last segment */
+		*is_empty = true;
+
+		if (n)
+			memset((char *) buf, 0, BLCKSZ);
+	}
+
+	state->pageno++;
+
+	if (state->pageno >= SLRU_PAGES_PER_SEGMENT_OLD)
+	{
+		/* Start new segment */
+		state->segno++;
+		state->pageno = 0;
+		close_file(state, slru_filename_old);
+	}
+
+	return n;
+}
+
+static void
+write_new_segment_page(SLRUSegmentState *state, void *buf, bool is_empty)
+{
+	/*
+	 * Create a new segment file if we still didn't.  Creation is postponed
+	 * until the first non-empty page is found.  This helps not to create
+	 * completely empty segments.
+	 */
+	if (!state->file && !is_empty)
+	{
+		state->file = open_file(state, slru_filename_new, "wb",
+								"could not open target file \"%s\": %m");
+
+		/* Write zeroes to the previously skipped prefix */
+		if (state->pageno > 0)
+		{
+			char	zerobuf[BLCKSZ] = {0};
+
+			for (int64 i = 0; i < state->pageno; i++)
+			{
+				if (fwrite(zerobuf, sizeof(char), BLCKSZ, state->file) != BLCKSZ)
+					pg_fatal("could not write file \"%s\": %m",
+							 slru_filename_new(state->dir, state->segno));
+			}
+		}
+
+	}
+
+	/* Write page to the new segment (if it was created) */
+	if (state->file)
+	{
+		if (fwrite(buf, sizeof(char), BLCKSZ, state->file) != BLCKSZ)
+			pg_fatal("could not write file \"%s\": %m",
+					 slru_filename_new(state->dir, state->segno));
+	}
+
+	state->pageno++;
+
+	/*
+	 * Did we reach the maximum page number? Then close segment file and
+	 * create a new one on the next iteration
+	 */
+	if (state->pageno >= SLRU_PAGES_PER_SEGMENT)
+	{
+		state->segno++;
+		state->pageno = 0;
+		close_file(state, slru_filename_new);
+	}
+}
+
+/*
+ * Convert pg_xact segments.
+ */
+void
+convert_xact(const char *old_subdir, const char *new_subdir)
+{
+	SLRUSegmentState	oldseg = {0};
+	SLRUSegmentState	newseg = {0};
+	TransactionId		oldest_xid = old_cluster.controldata.chkpnt_oldstxid;
+	TransactionId		next_xid = old_cluster.controldata.chkpnt_nxtxid;
+	TransactionId		xid;
+	int64				pageno;
+	char				buf[BLCKSZ] = {0};
+
+	oldseg.dir = old_subdir;
+	newseg.dir = new_subdir;
+
+	pageno = oldest_xid / CLOG_XACTS_PER_PAGE;
+
+	oldseg.segno = pageno / SLRU_PAGES_PER_SEGMENT_OLD;
+	oldseg.pageno = pageno % SLRU_PAGES_PER_SEGMENT_OLD;
+
+	newseg.segno = pageno / SLRU_PAGES_PER_SEGMENT;
+	newseg.pageno = pageno % SLRU_PAGES_PER_SEGMENT;
+
+	if (next_xid < oldest_xid)
+		next_xid += (TransactionId) 1 << 32; /* wraparound */
+
+	/* Copy xid flags reading only needed segment pages */
+	for (xid = oldest_xid & ~(CLOG_XACTS_PER_PAGE - 1);
+		 xid <= ((next_xid - 1) & ~(CLOG_XACTS_PER_PAGE - 1));
+		 xid += CLOG_XACTS_PER_PAGE)
+	{
+		bool		is_empty;
+
+		/* Handle possible segment wraparound */
+		if (oldseg.segno > MaxTransactionId32 / CLOG_XACTS_PER_PAGE / SLRU_PAGES_PER_SEGMENT_OLD)
+		{
+			pageno = (MaxTransactionId32 + 1) / CLOG_XACTS_PER_PAGE;
+
+			Assert(oldseg.segno == pageno / SLRU_PAGES_PER_SEGMENT_OLD);
+			Assert(!oldseg.pageno);
+			Assert(!oldseg.file);
+			oldseg.segno = 0;
+
+			Assert(newseg.segno == pageno / SLRU_PAGES_PER_SEGMENT);
+			Assert(!newseg.pageno);
+			Assert(!newseg.file);
+			newseg.segno = 0;
+		}
+
+		read_old_segment_page(&oldseg, buf, &is_empty);
+		write_new_segment_page(&newseg, buf, is_empty);
+	}
+
+	/* Release resources */
+	close_file(&oldseg, slru_filename_old);
+	close_file(&newseg, slru_filename_new);
+}
+
+static inline SLRUSegmentState
+create_slru_segment_state(MultiXactId mxid,
+						  int offsets_per_page,
+						  int pages_per_segment,
+						  char *dir)
+{
+	SLRUSegmentState	seg = {0};
+	int64				n;
+
+	n = mxid / offsets_per_page;
+	seg.pageno = n % pages_per_segment;
+	seg.segno = n / pages_per_segment;
+	seg.dir = dir;
+
+	return seg;
+}
+
+/*
+ * Convert pg_multixact/offsets segments and return oldest mxid offset.
+ */
+MultiXactOffset
+convert_multixact_offsets(const char *old_subdir, const char *new_subdir)
+{
+	SLRUSegmentState		oldseg,
+							newseg;
+	MultiXactOffset32		oldbuf[MULTIXACT_OFFSETS_PER_PAGE_OLD] = {0};
+	MultiXactOffset			newbuf[MULTIXACT_OFFSETS_PER_PAGE] = {0};
+	MultiXactOffset32		oldest_mxoff = 0;
+	MultiXactId				oldest_mxid,
+							next_mxid,
+							mxid;
+	uint64					old_entry,
+							new_entry;
+	bool					oldest_mxoff_known = false;
+
+	StaticAssertStmt((sizeof(oldbuf) == BLCKSZ && sizeof(newbuf) == BLCKSZ),
+					 "buf should be BLCKSZ");
+
+	oldest_mxid = old_cluster.controldata.chkpnt_oldstMulti;
+
+	oldseg = create_slru_segment_state(oldest_mxid,
+									   MULTIXACT_OFFSETS_PER_PAGE_OLD,
+									   SLRU_PAGES_PER_SEGMENT_OLD,
+									   psprintf("%s/%s", old_cluster.pgdata,
+												old_subdir));
+
+	newseg = create_slru_segment_state(oldest_mxid,
+									   MULTIXACT_OFFSETS_PER_PAGE,
+									   SLRU_PAGES_PER_SEGMENT,
+									   psprintf("%s/%s", new_cluster.pgdata,
+												new_subdir));
+
+	old_entry = oldest_mxid % MULTIXACT_OFFSETS_PER_PAGE_OLD;
+	new_entry = oldest_mxid % MULTIXACT_OFFSETS_PER_PAGE;
+
+	next_mxid = old_cluster.controldata.chkpnt_nxtmulti;
+	if (next_mxid < oldest_mxid)
+		next_mxid += (MultiXactId) 1 << 32;	/* wraparound */
+
+	prep_status("Converting old %s to new format", old_subdir);
+
+	/* Copy mxid offsets reading only needed segment pages */
+	for (mxid = oldest_mxid; mxid < next_mxid; old_entry = 0)
+	{
+		int			oldlen;
+		bool		is_empty;
+
+		/* Handle possible segment wraparound */
+		if (oldseg.segno > MaxMultiXactId32 / MULTIXACT_OFFSETS_PER_PAGE_OLD / SLRU_PAGES_PER_SEGMENT_OLD)	/* 0xFFFF */
+			oldseg.segno = 0;
+
+		oldlen = read_old_segment_page(&oldseg, oldbuf, &is_empty);
+
+		if (oldlen == 0 || is_empty)
+			pg_fatal("cannot read page %lld from segment: %s\n",
+					 (long long) oldseg.pageno,
+					 slru_filename_old(oldseg.dir, oldseg.segno));
+
+		/* Save oldest mxid offset */
+		if (!oldest_mxoff_known)
+		{
+			oldest_mxoff = oldbuf[old_entry];
+			oldest_mxoff_known = true;
+		}
+
+		/* Skip wrapped-around invalid MultiXactIds */
+		if (mxid == (MultiXactId) 1 << 32)
+		{
+			Assert(oldseg.segno == 0);
+			Assert(oldseg.pageno == 1);
+			Assert(old_entry == 0);
+			mxid += FirstMultiXactId;
+			old_entry = FirstMultiXactId;
+		}
+
+		/* Copy entries to the new page */
+		for (; mxid < next_mxid && old_entry < MULTIXACT_OFFSETS_PER_PAGE_OLD;
+			 mxid++, old_entry++)
+		{
+			MultiXactOffset mxoff = oldbuf[old_entry];
+
+			/* Handle possible offset wraparound (1 becomes 2^32) */
+			if (mxoff < oldest_mxoff)
+				mxoff += ((MultiXactOffset) 1 << 32) - 1;
+
+			/* Subtract oldest_mxoff, so new offsets will start from 1 */
+			newbuf[new_entry++] = mxoff - oldest_mxoff + 1;
+
+			if (new_entry >= MULTIXACT_OFFSETS_PER_PAGE)
+			{
+				/* Write new page */
+				write_new_segment_page(&newseg, newbuf, false);
+				new_entry = 0;
+			}
+		}
+	}
+
+	/* Write the last incomplete page */
+	if (new_entry > 0 || oldest_mxid == next_mxid)
+	{
+		memset(&newbuf[new_entry], 0,
+			   sizeof(newbuf[0]) * (MULTIXACT_OFFSETS_PER_PAGE - new_entry));
+		write_new_segment_page(&newseg, newbuf, false);
+	}
+
+	/* Use next_mxoff as oldest_mxoff, if oldest_mxid == next_mxid */
+	if (!oldest_mxoff_known)
+	{
+		Assert(oldest_mxid == next_mxid);
+		oldest_mxoff = (MultiXactOffset) old_cluster.controldata.chkpnt_nxtmxoff;
+	}
+
+	/* Release resources */
+	close_file(&oldseg, slru_filename_old);
+	close_file(&newseg, slru_filename_new);
+
+	pfree((char *) oldseg.dir);
+	pfree((char *) newseg.dir);
+
+	check_ok();
+
+	return oldest_mxoff;
+}
+
+/*
+ * Convert pg_multixact/members segments, offsets will start from 1.
+ */
+void
+convert_multixact_members(const char *old_subdir, const char *new_subdir,
+						  MultiXactOffset oldest_mxoff)
+{
+	MultiXactOffset		next_mxoff,
+						mxoff;
+	SLRUSegmentState	oldseg,
+						newseg;
+	char				oldbuf[BLCKSZ] = {0},
+						newbuf[BLCKSZ] = {0};
+	int					newgroup,
+						newmember;
+	char			   *newflag = newbuf;
+	TransactionId	   *newxid;
+	int					oldidx,
+						newidx;
+
+	prep_status("Converting old %s to new format", old_subdir);
+
+	next_mxoff = (MultiXactOffset) old_cluster.controldata.chkpnt_nxtmxoff;
+	if (next_mxoff < oldest_mxoff)
+		next_mxoff += (MultiXactOffset) 1 << 32;
+
+	newxid = (TransactionId *) (newflag + MXACT_MEMBER_FLAGS_PER_BYTE * MULTIXACT_MEMBERS_PER_MEMBERGROUP);
+
+	/* Initialize old starting position */
+	oldidx = oldest_mxoff % MULTIXACT_MEMBERS_PER_PAGE_OLD;
+	oldseg = create_slru_segment_state(oldest_mxoff,
+									   MULTIXACT_MEMBERS_PER_PAGE_OLD,
+									   SLRU_PAGES_PER_SEGMENT_OLD,
+									   psprintf("%s/%s", old_cluster.pgdata,
+												old_subdir));
+
+	/* Initialize empty new segment */
+	newseg = create_slru_segment_state(0, 1, 1,
+									   psprintf("%s/%s", new_cluster.pgdata,
+									   new_subdir));
+
+	/* Initialize new starting position (skip invalid zero offset) */
+	newgroup = 0;
+	newidx = 1;
+	newmember = 1;
+	newflag++;
+	newxid++;
+
+	/* Iterate through the original directory */
+	for (mxoff = oldest_mxoff; mxoff < next_mxoff; oldidx = 0)
+	{
+		bool		old_is_empty;
+		int			oldlen;
+		int			ngroups;
+		int			oldgroup;
+		int			oldmember;
+
+		oldlen = read_old_segment_page(&oldseg, oldbuf, &old_is_empty);
+
+		if (oldlen == 0 || old_is_empty)
+			pg_fatal("cannot read page %lld from segment: %s\n",
+					 (long long) oldseg.pageno,
+					 slru_filename_old(oldseg.dir, oldseg.segno));
+
+		ngroups = oldlen / MULTIXACT_MEMBERGROUP_SIZE_OLD;
+
+		/* Iterate through old member groups */
+		for (oldgroup = oldidx / MULTIXACT_MEMBERS_PER_MEMBERGROUP_OLD,
+			 oldmember = oldidx % MULTIXACT_MEMBERS_PER_MEMBERGROUP_OLD;
+			 oldgroup < ngroups && mxoff < next_mxoff;
+			 oldgroup++, oldmember = 0)
+		{
+			char	   *oldflag = (char *) oldbuf + oldgroup * MULTIXACT_MEMBERGROUP_SIZE_OLD;
+			TransactionId32 *oldxid = (TransactionId32 *) (oldflag + MULTIXACT_FLAGBYTES_PER_GROUP_OLD);
+
+			oldxid += oldmember;
+			oldflag += oldmember;
+
+			/* Iterate through old members */
+			for (int i = 0;
+				 i < MULTIXACT_MEMBERS_PER_MEMBERGROUP_OLD && mxoff < next_mxoff;
+				 i++)
+			{
+				/* Copy member's xid and flags to the new page */
+				*newflag++ = *oldflag++;
+				*newxid++ = (TransactionId) * oldxid++;
+
+				newidx++;
+				oldidx++;
+				mxoff++;
+
+				if (++newmember >= MULTIXACT_MEMBERS_PER_MEMBERGROUP)
+				{
+					/* Start next member group */
+					newmember = 0;
+
+					if (++newgroup >= MULTIXACT_MEMBERGROUPS_PER_PAGE)
+					{
+						/* Write current page and start new */
+						newgroup = 0;
+						newidx = 0;
+						write_new_segment_page(&newseg, newbuf, false);
+						memset(newbuf, 0, BLCKSZ);
+					}
+
+					newflag = (char *) newbuf + newgroup * MULTIXACT_MEMBERGROUP_SIZE;
+					newxid = (TransactionId *) (newflag + MXACT_MEMBER_FLAGS_PER_BYTE * MULTIXACT_MEMBERS_PER_MEMBERGROUP);
+				}
+
+				/* Handle offset wraparound */
+				if (mxoff > MaxMultiXactOffset32)
+				{
+					Assert(mxoff == (MultiXactOffset) 1 << 32);
+					Assert(oldseg.segno == MaxMultiXactOffset32 / MULTIXACT_MEMBERS_PER_PAGE_OLD / SLRU_PAGES_PER_SEGMENT_OLD);
+					Assert(oldseg.pageno == MaxMultiXactOffset32 / MULTIXACT_MEMBERS_PER_PAGE_OLD % SLRU_PAGES_PER_SEGMENT_OLD);
+					Assert(oldmember == MaxMultiXactOffset32 % MULTIXACT_MEMBERS_PER_PAGE_OLD);
+
+					/* Switch to segment 0000 */
+					close_file(&oldseg, slru_filename_old);
+					oldseg.segno = 0;
+					oldseg.pageno = 0;
+
+					oldidx = 1; /* skip invalid zero mxid offset */
+				}
+			}
+		}
+	}
+
+	/* Write last page, unless it is empty */
+	if (newflag > (char *) newbuf || oldest_mxoff == next_mxoff)
+		write_new_segment_page(&newseg, newbuf, false);
+
+	/* Release resources */
+	close_file(&oldseg, slru_filename_old);
+	close_file(&newseg, slru_filename_new);
+
+	pfree((char *) oldseg.dir);
+	pfree((char *) newseg.dir);
+
+	check_ok();
+}
diff --git a/src/bin/pg_upgrade/t/002_pg_upgrade.pl b/src/bin/pg_upgrade/t/002_pg_upgrade.pl
index 2f9b13bf0a..30a77e3a54 100644
--- a/src/bin/pg_upgrade/t/002_pg_upgrade.pl
+++ b/src/bin/pg_upgrade/t/002_pg_upgrade.pl
@@ -60,7 +60,7 @@ my $oldnode =
 # To increase coverage of non-standard segment size and group access without
 # increasing test runtime, run these tests with a custom setting.
 # --allow-group-access and --wal-segsize have been added in v11.
-$oldnode->init(extra => [ '--wal-segsize', '1', '--allow-group-access' ]);
+$oldnode->init(extra => [ '--wal-segsize', '1', '--allow-group-access', '-x', '21000000000' ]);
 $oldnode->start;
 
 # The default location of the source code is the root of this directory.
@@ -145,9 +145,17 @@ if (defined($ENV{oldinstall}))
 		'ran adapt script');
 }
 
+$oldnode->safe_psql('regression',
+	"CREATE TABLE t1 (id SERIAL NOT NULL PRIMARY KEY, plt text, pln NUMERIC(8, 4));
+	 INSERT INTO t1 (plt, pln) SELECT md5(random()::text), random() * 9999 FROM generate_series(1, 1000);");
+my $relfrozenxid = $oldnode->safe_psql('regression',
+	"SELECT relfrozenxid FROM pg_class WHERE relname = 't1';");
+my $relminmxid = $oldnode->safe_psql('regression',
+	"SELECT relminmxid FROM pg_class WHERE relname = 't1';");
+
 # Initialize a new node for the upgrade.
 my $newnode = PostgreSQL::Test::Cluster->new('new_node');
-$newnode->init(extra => [ '--wal-segsize', '1', '--allow-group-access' ]);
+$newnode->init(extra => [ '--wal-segsize', '1', '--allow-group-access', '-x', '21000000000' ]);
 my $newbindir = $newnode->config_data('--bindir');
 my $oldbindir = $oldnode->config_data('--bindir');
 
@@ -263,6 +271,16 @@ ok( !-d $newnode->data_dir . "/pg_upgrade_output.d",
 
 $newnode->start;
 
+my $relfrozenxid_new = $newnode->safe_psql('regression',
+	"SELECT relfrozenxid FROM pg_class WHERE relname = 't1';");
+
+is($relfrozenxid_new, $relfrozenxid, 'old and new relfrozenxid match after pg_upgrade');
+
+my $relminmxid_new = $newnode->safe_psql('regression',
+	"SELECT relminmxid FROM pg_class WHERE relname = 't1';");
+
+is($relminmxid_new, $relminmxid, 'old and new relminmxid match after pg_upgrade');
+
 # Check if there are any logs coming from pg_upgrade, that would only be
 # retained on failure.
 my $log_path = $newnode->data_dir . "/pg_upgrade_output.d";
diff --git a/src/bin/pg_upgrade/version.c b/src/bin/pg_upgrade/version.c
index c694558c3d..10dcd60337 100644
--- a/src/bin/pg_upgrade/version.c
+++ b/src/bin/pg_upgrade/version.c
@@ -9,6 +9,7 @@
 
 #include "postgres_fe.h"
 
+#include "access/transam.h"
 #include "catalog/pg_class_d.h"
 #include "fe_utils/string_utils.h"
 #include "pg_upgrade.h"
@@ -238,19 +239,21 @@ old_9_6_check_for_unknown_data_type_usage(ClusterInfo *cluster)
 }
 
 /*
- * old_9_6_invalidate_hash_indexes()
- *	9.6 -> 10
- *	Hash index binary format has changed from 9.6->10.0
+ * invalidate_indexes()
+ *	Invalidates all indexes satisfying given predicate.
  */
-void
-old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
+static void
+invalidate_indexes(ClusterInfo *cluster, bool check_mode,
+				   const char *name, const char *pred)
 {
 	int			dbnum;
 	FILE	   *script = NULL;
 	bool		found = false;
-	char	   *output_path = "reindex_hash.sql";
+	char		output_path[MAXPGPATH];
+
+	snprintf(output_path, sizeof(output_path), "reindex_%s.sql", name);
 
-	prep_status("Checking for hash indexes");
+	prep_status("Checking for %s indexes", name);
 
 	for (dbnum = 0; dbnum < cluster->dbarr.ndbs; dbnum++)
 	{
@@ -263,9 +266,16 @@ old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
 		DbInfo	   *active_db = &cluster->dbarr.dbs[dbnum];
 		PGconn	   *conn = connectToServer(cluster, active_db->db_name);
 
-		/* find hash indexes */
-		res = executeQueryOrDie(conn,
-								"SELECT n.nspname, c.relname "
+
+		/*
+		 * Find indexes satisfying predicate.
+		 *
+		 * System indexes (with oids < FirstNormalObjectId) are excluded from
+		 * the search as they are recreated in the new cluster during initdb.
+		 */
+		res = executeQueryOrDie(
+								conn,
+								"SELECT n.nspname, c.relname, i.indexrelid "
 								"FROM	pg_catalog.pg_class c, "
 								"		pg_catalog.pg_index i, "
 								"		pg_catalog.pg_am a, "
@@ -273,8 +283,11 @@ old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
 								"WHERE	i.indexrelid = c.oid AND "
 								"		c.relam = a.oid AND "
 								"		c.relnamespace = n.oid AND "
-								"		a.amname = 'hash'"
-			);
+								"		i.indexrelid >= '%u'::pg_catalog.oid AND "
+								"		%s "
+								"ORDER BY i.indexrelid ASC",
+								FirstNormalObjectId,
+								pred);
 
 		ntups = PQntuples(res);
 		i_nspname = PQfnumber(res, "nspname");
@@ -307,8 +320,14 @@ old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
 
 		if (!check_mode && db_used)
 		{
-			/* mark hash indexes as invalid */
-			PQclear(executeQueryOrDie(conn,
+			/*
+			 * Mark indexes satisfying predicate as invalid.
+			 *
+			 * System indexes (with oids < FirstNormalObjectId) are excluded
+			 * from the search (see above).
+			 */
+			PQclear(executeQueryOrDie(
+									  conn,
 									  "UPDATE pg_catalog.pg_index i "
 									  "SET	indisvalid = false "
 									  "FROM	pg_catalog.pg_class c, "
@@ -317,7 +336,10 @@ old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
 									  "WHERE	i.indexrelid = c.oid AND "
 									  "		c.relam = a.oid AND "
 									  "		c.relnamespace = n.oid AND "
-									  "		a.amname = 'hash'"));
+									  "		i.indexrelid >= '%u'::pg_catalog.oid AND "
+									  "		%s",
+									  FirstNormalObjectId,
+									  pred));
 		}
 
 		PQfinish(conn);
@@ -331,24 +353,37 @@ old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
 		report_status(PG_WARNING, "warning");
 		if (check_mode)
 			pg_log(PG_WARNING, "\n"
-				   "Your installation contains hash indexes.  These indexes have different\n"
+				   "Your installation contains %s indexes.  These indexes have different\n"
 				   "internal formats between your old and new clusters, so they must be\n"
 				   "reindexed with the REINDEX command.  After upgrading, you will be given\n"
-				   "REINDEX instructions.\n\n");
+				   "REINDEX instructions.\n\n",
+				   name);
 		else
 			pg_log(PG_WARNING, "\n"
-				   "Your installation contains hash indexes.  These indexes have different\n"
+				   "Your installation contains %s indexes.  These indexes have different\n"
 				   "internal formats between your old and new clusters, so they must be\n"
 				   "reindexed with the REINDEX command.  The file\n"
 				   "    %s\n"
 				   "when executed by psql by the database superuser will recreate all invalid\n"
 				   "indexes; until then, none of these indexes will be used.\n\n",
+				   name,
 				   output_path);
 	}
 	else
 		check_ok();
 }
 
+/*
+ * old_9_6_invalidate_hash_indexes()
+ *	9.6 -> 10
+ *	Hash index binary format has changed from 9.6->10.0
+ */
+void
+old_9_6_invalidate_hash_indexes(ClusterInfo *cluster, bool check_mode)
+{
+	invalidate_indexes(cluster, check_mode, "hash", "a.amname = 'hash'");
+}
+
 /*
  * old_11_check_for_sql_identifier_data_type_usage()
  *	11 -> 12
@@ -458,3 +493,36 @@ report_extension_updates(ClusterInfo *cluster)
 	else
 		check_ok();
 }
+
+/*
+ * invalidate_spgist_indexes()
+ *	32bit -> 64bit
+ *	SP-GIST contains xids.
+ */
+void
+invalidate_spgist_indexes(ClusterInfo *cluster, bool check_mode)
+{
+	invalidate_indexes(cluster, check_mode, "spgist", "a.amname = 'spgist'");
+}
+
+/*
+ * invalidate_gin_indexes()
+ *	32bit -> 64bit
+ *	Gin indexes contains xids in deleted pages.
+ */
+void
+invalidate_gin_indexes(ClusterInfo *cluster, bool check_mode)
+{
+	invalidate_indexes(cluster, check_mode, "gin", "a.amname = 'gin'");
+}
+
+/*
+ * invalidate_external_indexes()
+ *	Generate script to REINDEX non standard external indexes (like RUM etc)
+ */
+void
+invalidate_external_indexes(ClusterInfo *cluster, bool check_mode)
+{
+	invalidate_indexes(cluster, check_mode, "external",
+					   "NOT a.amname IN ('btree', 'hash', 'gist', 'gin', 'spgist', 'brin')");
+}
diff --git a/src/bin/pg_verifybackup/t/003_corruption.pl b/src/bin/pg_verifybackup/t/003_corruption.pl
index f1ceb4a4bd..f4109471ac 100644
--- a/src/bin/pg_verifybackup/t/003_corruption.pl
+++ b/src/bin/pg_verifybackup/t/003_corruption.pl
@@ -174,7 +174,7 @@ sub mutilate_extra_tablespace_file
 sub mutilate_missing_file
 {
 	my ($backup_path) = @_;
-	my $pathname = "$backup_path/pg_xact/000000000000";
+	my $pathname = "$backup_path/pg_xact/000000123000";
 	unlink($pathname) || die "$pathname: $!";
 	return;
 }
diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c
index 649ac0f485..9bcf58ec24 100644
--- a/src/bin/pg_waldump/pg_waldump.c
+++ b/src/bin/pg_waldump/pg_waldump.c
@@ -919,7 +919,7 @@ main(int argc, char **argv)
 				config.filter_by_fpw = true;
 				break;
 			case 'x':
-				if (sscanf(optarg, "%u", &config.filter_by_xid) != 1)
+				if (sscanf(optarg, "%" INT64_MODIFIER "u", &config.filter_by_xid) != 1)
 				{
 					pg_log_error("invalid transaction ID specification: \"%s\"",
 								 optarg);
diff --git a/src/include/access/clog.h b/src/include/access/clog.h
index 543f2e2643..73bc172309 100644
--- a/src/include/access/clog.h
+++ b/src/include/access/clog.h
@@ -31,7 +31,7 @@ typedef int XidStatus;
 
 typedef struct xl_clog_truncate
 {
-	int			pageno;
+	int64		pageno;
 	TransactionId oldestXact;
 	Oid			oldestXactDb;
 } xl_clog_truncate;
diff --git a/src/include/access/ginblock.h b/src/include/access/ginblock.h
index 9347f464f3..4db042c319 100644
--- a/src/include/access/ginblock.h
+++ b/src/include/access/ginblock.h
@@ -133,8 +133,15 @@ typedef struct GinMetaPageData
  * We should reclaim deleted page only once every transaction started before
  * its deletion is over.
  */
-#define GinPageGetDeleteXid(page) ( ((PageHeader) (page))->pd_prune_xid )
-#define GinPageSetDeleteXid(page, xid) ( ((PageHeader) (page))->pd_prune_xid = xid)
+#define GinPageGetDeleteXid(page) ( \
+	(((PageHeader) (page))->pd_upper == BLCKSZ - sizeof(GinPageOpaqueData) - sizeof(TransactionId)) ? \
+	*((TransactionId *) ((char *) (page) + BLCKSZ - sizeof(GinPageOpaqueData) - sizeof(TransactionId))) : \
+	InvalidTransactionId )
+#define GinPageSetDeleteXid(page, xid) \
+	do { \
+		((PageHeader) (page))->pd_upper = BLCKSZ - sizeof(GinPageOpaqueData) - sizeof(TransactionId); \
+		*((TransactionId *) ((char *) (page) + BLCKSZ - sizeof(GinPageOpaqueData) - sizeof(TransactionId))) = xid; \
+	} while (false)
 extern bool GinPageIsRecyclable(Page page);
 
 /*
diff --git a/src/include/access/gist.h b/src/include/access/gist.h
index a3337627b8..41de3052fd 100644
--- a/src/include/access/gist.h
+++ b/src/include/access/gist.h
@@ -223,7 +223,7 @@ GistPageGetDeleteXid(Page page)
 		return ((GISTDeletedPageContents *) PageGetContents(page))->deleteXid;
 	}
 	else
-		return FullTransactionIdFromEpochAndXid(0, FirstNormalTransactionId);
+		return FullTransactionIdFromXid(FirstNormalTransactionId);
 }
 
 /*
diff --git a/src/include/access/heapam.h b/src/include/access/heapam.h
index abf62d9df7..9f01f4dc19 100644
--- a/src/include/access/heapam.h
+++ b/src/include/access/heapam.h
@@ -146,6 +146,10 @@ extern void ReleaseBulkInsertStatePin(BulkInsertState bistate);
 
 extern void heap_insert(Relation relation, HeapTuple tup, CommandId cid,
 						int options, BulkInsertState bistate);
+extern bool heap_page_prepare_for_xid(Relation relation, Buffer buffer,
+									  TransactionId xid, bool multi);
+extern void rewrite_page_prepare_for_xid(Page page, HeapTuple tup,
+										 bool is_toast);
 extern void heap_multi_insert(Relation relation, struct TupleTableSlot **slots,
 							  int ntuples, CommandId cid, int options,
 							  BulkInsertState bistate);
@@ -164,14 +168,14 @@ extern TM_Result heap_lock_tuple(Relation relation, HeapTuple tuple,
 								 Buffer *buffer, struct TM_FailureData *tmfd);
 
 extern void heap_inplace_update(Relation relation, HeapTuple tuple);
-extern bool heap_freeze_tuple(HeapTupleHeader tuple,
+extern bool heap_freeze_tuple(HeapTuple tuple,
 							  TransactionId relfrozenxid, TransactionId relminmxid,
 							  TransactionId cutoff_xid, TransactionId cutoff_multi);
-extern bool heap_tuple_would_freeze(HeapTupleHeader tuple, TransactionId cutoff_xid,
+extern bool heap_tuple_would_freeze(HeapTuple htup, TransactionId cutoff_xid,
 									MultiXactId cutoff_multi,
 									TransactionId *relfrozenxid_out,
 									MultiXactId *relminmxid_out);
-extern bool heap_tuple_needs_eventual_freeze(HeapTupleHeader tuple);
+extern bool heap_tuple_needs_eventual_freeze(HeapTuple htup);
 
 extern void simple_heap_insert(Relation relation, HeapTuple tup);
 extern void simple_heap_delete(Relation relation, ItemPointer tid);
@@ -189,12 +193,16 @@ extern int	heap_page_prune(Relation relation, Buffer buffer,
 							TransactionId old_snap_xmin,
 							TimestampTz old_snap_ts_ts,
 							int *nnewlpdead,
-							OffsetNumber *off_loc);
+							OffsetNumber *off_loc,
+							bool repairFragmentation);
 extern void heap_page_prune_execute(Buffer buffer,
 									OffsetNumber *redirected, int nredirected,
 									OffsetNumber *nowdead, int ndead,
-									OffsetNumber *nowunused, int nunused);
-extern void heap_get_root_tuples(Page page, OffsetNumber *root_offsets);
+									OffsetNumber *nowunused, int nunused,
+									bool repairFragmentation,
+									bool is_toast);
+extern void heap_get_root_tuples(Relation relation, Page page,
+								 OffsetNumber *root_offsets);
 
 /* in heap/vacuumlazy.c */
 struct VacuumParams;
@@ -212,7 +220,7 @@ extern HTSV_Result HeapTupleSatisfiesVacuumHorizon(HeapTuple stup, Buffer buffer
 												   TransactionId *dead_after);
 extern void HeapTupleSetHintBits(HeapTupleHeader tuple, Buffer buffer,
 								 uint16 infomask, TransactionId xid);
-extern bool HeapTupleHeaderIsOnlyLocked(HeapTupleHeader tuple);
+extern bool HeapTupleIsOnlyLocked(HeapTuple htup);
 extern bool XidInMVCCSnapshot(TransactionId xid, Snapshot snapshot);
 extern bool HeapTupleIsSurelyDead(HeapTuple htup,
 								  struct GlobalVisState *vistest);
diff --git a/src/include/access/heapam_xlog.h b/src/include/access/heapam_xlog.h
index 1705e736be..e8f7c8522c 100644
--- a/src/include/access/heapam_xlog.h
+++ b/src/include/access/heapam_xlog.h
@@ -59,6 +59,8 @@
 #define XLOG_HEAP2_LOCK_UPDATED 0x60
 #define XLOG_HEAP2_NEW_CID		0x70
 
+#define XLOG_HEAP3_BASE_SHIFT	0x00
+
 /*
  * xl_heap_insert/xl_heap_multi_insert flag values, 8 bits are available.
  */
@@ -98,6 +100,7 @@
 #define XLH_DELETE_CONTAINS_OLD_KEY				(1<<2)
 #define XLH_DELETE_IS_SUPER						(1<<3)
 #define XLH_DELETE_IS_PARTITION_MOVE			(1<<4)
+#define XLH_DELETE_PAGE_ON_TOAST_RELATION		(1<<5)
 
 /* convenience macro for checking whether any form of old tuple was logged */
 #define XLH_DELETE_CONTAINS_OLD						\
@@ -240,15 +243,18 @@ typedef struct xl_heap_update
  *
  * Acquires a full cleanup lock.
  */
+#define XLH_PRUNE_ON_TOAST_RELATION		0x01
+
 typedef struct xl_heap_prune
 {
 	TransactionId latestRemovedXid;
 	uint16		nredirected;
 	uint16		ndead;
+	uint8		flags;
 	/* OFFSET NUMBERS are in the block reference 0 */
 } xl_heap_prune;
 
-#define SizeOfHeapPrune (offsetof(xl_heap_prune, ndead) + sizeof(uint16))
+#define SizeOfHeapPrune (offsetof(xl_heap_prune, flags) + sizeof(uint8))
 
 /*
  * The vacuum page record is similar to the prune record, but can only mark
@@ -336,13 +342,16 @@ typedef struct xl_heap_freeze_tuple
  * Backup block 0's data contains an array of xl_heap_freeze_tuple structs,
  * one for each tuple.
  */
+#define XLH_FREEZE_PAGE_ON_TOAST_RELATION		0x01
+
 typedef struct xl_heap_freeze_page
 {
 	TransactionId cutoff_xid;
 	uint16		ntuples;
+	uint8		flags;
 } xl_heap_freeze_page;
 
-#define SizeOfHeapFreezePage (offsetof(xl_heap_freeze_page, ntuples) + sizeof(uint16))
+#define SizeOfHeapFreezePage (offsetof(xl_heap_freeze_page, flags) + sizeof(uint8))
 
 /*
  * This is what we need to know about setting a visibility map bit
@@ -389,7 +398,19 @@ typedef struct xl_heap_rewrite_mapping
 	XLogRecPtr	start_lsn;		/* Insert LSN at begin of rewrite */
 } xl_heap_rewrite_mapping;
 
-extern void HeapTupleHeaderAdvanceLatestRemovedXid(HeapTupleHeader tuple,
+#define XLH_BASE_SHIFT_ON_TOAST_RELATION	0x01
+
+/* shift the base of xids on heap page */
+typedef struct xl_heap_base_shift
+{
+	int64		delta;			/* delta value to shift the base */
+	bool		multi;			/* true to shift multixact base */
+	uint8		flags;
+}			xl_heap_base_shift;
+
+#define SizeOfHeapBaseShift (offsetof(xl_heap_base_shift, flags) + sizeof(uint8))
+
+extern void HeapTupleHeaderAdvanceLatestRemovedXid(HeapTuple tuple,
 												   TransactionId *latestRemovedXid);
 
 extern void heap_redo(XLogReaderState *record);
@@ -399,12 +420,15 @@ extern void heap_mask(char *pagedata, BlockNumber blkno);
 extern void heap2_redo(XLogReaderState *record);
 extern void heap2_desc(StringInfo buf, XLogReaderState *record);
 extern const char *heap2_identify(uint8 info);
+extern void heap3_redo(XLogReaderState *record);
+extern void heap3_desc(StringInfo buf, XLogReaderState *record);
+extern const char *heap3_identify(uint8 info);
 extern void heap_xlog_logical_rewrite(XLogReaderState *r);
 
 extern XLogRecPtr log_heap_freeze(Relation reln, Buffer buffer,
 								  TransactionId cutoff_xid, xl_heap_freeze_tuple *tuples,
 								  int ntuples);
-extern bool heap_prepare_freeze_tuple(HeapTupleHeader tuple,
+extern bool heap_prepare_freeze_tuple(HeapTuple htup,
 									  TransactionId relfrozenxid,
 									  TransactionId relminmxid,
 									  TransactionId cutoff_xid,
@@ -413,9 +437,12 @@ extern bool heap_prepare_freeze_tuple(HeapTupleHeader tuple,
 									  bool *totally_frozen,
 									  TransactionId *relfrozenxid_out,
 									  MultiXactId *relminmxid_out);
-extern void heap_execute_freeze_tuple(HeapTupleHeader tuple,
+extern void heap_execute_freeze_tuple(HeapTuple tuple,
 									  xl_heap_freeze_tuple *xlrec_tp);
 extern XLogRecPtr log_heap_visible(RelFileLocator rlocator, Buffer heap_buffer,
 								   Buffer vm_buffer, TransactionId cutoff_xid, uint8 flags);
+extern void heap_execute_freeze_tuple_page(Page page, HeapTupleHeader htup,
+										   xl_heap_freeze_tuple *xlrec_tp,
+										   bool is_toast);
 
 #endif							/* HEAPAM_XLOG_H */
diff --git a/src/include/access/heaptoast.h b/src/include/access/heaptoast.h
index a75699054a..3916a5f05e 100644
--- a/src/include/access/heaptoast.h
+++ b/src/include/access/heaptoast.h
@@ -20,10 +20,19 @@
 /*
  * Find the maximum size of a tuple if there are to be N tuples per page.
  */
+#if MAXIMUM_ALIGNOF == 8
 #define MaximumBytesPerTuple(tuplesPerPage) \
 	MAXALIGN_DOWN((BLCKSZ - \
-				   MAXALIGN(SizeOfPageHeaderData + (tuplesPerPage) * sizeof(ItemIdData))) \
+				   MAXALIGN(SizeOfPageHeaderData + (tuplesPerPage) * sizeof(ItemIdData)) - MAXALIGN(sizeof(HeapPageSpecialData))) \
 				  / (tuplesPerPage))
+#elif MAXIMUM_ALIGNOF == 4
+#define MaximumBytesPerTuple(tuplesPerPage) \
+	MAXALIGN_DOWN((BLCKSZ - \
+				   MAXALIGN(SizeOfPageHeaderData + (tuplesPerPage) * sizeof(ItemIdData)) - MAXALIGN(sizeof(ToastPageSpecialData))) \
+				  / (tuplesPerPage))
+#else
+#error "unknown arch bitness"
+#endif
 
 /*
  * These symbols control toaster activation.  If a tuple is larger than
diff --git a/src/include/access/htup.h b/src/include/access/htup.h
index a4bc7256ed..bd77a018f5 100644
--- a/src/include/access/htup.h
+++ b/src/include/access/htup.h
@@ -54,6 +54,12 @@ typedef MinimalTupleData *MinimalTuple;
  *	 this can't be told apart from case #1 by inspection; code setting up
  *	 or destroying this representation has to know what it's doing.
  *
+ * t_xmin and t_xmax are TransactionId values stored in heap tuple header.
+ * Normally they are calculated from ShortTransactionId-sized on-disk tuple
+ * xmin/xmax representation:
+ * t_data->t_choice.t_heap.t_xmin/t_data->t_choice.t_heap.t_xmin
+ * and pd_xid_base and pd_multi_base commmon values for all tuples on a page.
+ *
  * t_len should always be valid, except in the pointer-to-nothing case.
  * t_self and t_tableOid should be valid if the HeapTupleData points to
  * a disk buffer, or if it represents a copy of a tuple on disk.  They
@@ -61,10 +67,12 @@ typedef MinimalTupleData *MinimalTuple;
  */
 typedef struct HeapTupleData
 {
+	TransactionId t_xmin;		/* base value for normal transaction ids */
+	TransactionId t_xmax;		/* base value for mutlixact */
 	uint32		t_len;			/* length of *t_data */
 	ItemPointerData t_self;		/* SelfItemPointer */
 	Oid			t_tableOid;		/* table the tuple came from */
-#define FIELDNO_HEAPTUPLEDATA_DATA 3
+#define FIELDNO_HEAPTUPLEDATA_DATA 5
 	HeapTupleHeader t_data;		/* -> tuple header and data */
 } HeapTupleData;
 
@@ -78,12 +86,12 @@ typedef HeapTupleData *HeapTuple;
 #define HeapTupleIsValid(tuple) PointerIsValid(tuple)
 
 /* HeapTupleHeader functions implemented in utils/time/combocid.c */
-extern CommandId HeapTupleHeaderGetCmin(HeapTupleHeader tup);
-extern CommandId HeapTupleHeaderGetCmax(HeapTupleHeader tup);
-extern void HeapTupleHeaderAdjustCmax(HeapTupleHeader tup,
+extern CommandId HeapTupleGetCmin(HeapTuple tup);
+extern CommandId HeapTupleGetCmax(HeapTuple tup);
+extern void HeapTupleHeaderAdjustCmax(HeapTuple tup,
 									  CommandId *cmax, bool *iscombo);
 
 /* Prototype for HeapTupleHeader accessors in heapam.c */
-extern TransactionId HeapTupleGetUpdateXid(HeapTupleHeader tuple);
+extern TransactionId HeapTupleGetUpdateXid(HeapTuple tuple);
 
 #endif							/* HTUP_H */
diff --git a/src/include/access/htup_details.h b/src/include/access/htup_details.h
index 51a60eda08..c089e80fa3 100644
--- a/src/include/access/htup_details.h
+++ b/src/include/access/htup_details.h
@@ -120,13 +120,13 @@
 
 typedef struct HeapTupleFields
 {
-	TransactionId t_xmin;		/* inserting xact ID */
-	TransactionId t_xmax;		/* deleting or locking xact ID */
+	ShortTransactionId t_xmin;	/* inserting xact ID */
+	ShortTransactionId t_xmax;	/* deleting or locking xact ID */
 
 	union
 	{
 		CommandId	t_cid;		/* inserting or deleting command ID, or both */
-		TransactionId t_xvac;	/* old-style VACUUM FULL xact ID */
+		ShortTransactionId t_xvac;	/* old-style VACUUM FULL xact ID */
 	}			t_field3;
 } HeapTupleFields;
 
@@ -222,7 +222,7 @@ struct HeapTupleHeaderData
  * HEAP_XMAX_LOCK_ONLY bit is set; or, for pg_upgrade's sake, if the Xmax is
  * not a multi and the EXCL_LOCK bit is set.
  *
- * See also HeapTupleHeaderIsOnlyLocked, which also checks for a possible
+ * See also HeapTupleIsOnlyLocked, which also checks for a possible
  * aborted updater transaction.
  *
  * Beware of multiple evaluations of the argument.
@@ -298,27 +298,85 @@ struct HeapTupleHeaderData
  */
 
 /*
- * HeapTupleHeaderGetRawXmin returns the "raw" xmin field, which is the xid
+ * Copy base values for xid and multixacts from one heap tuple to heap tuple.
+ * Should be called on tuple copy or making desc tuple on the base on src tuple
+ * saving visibility information.
+ */
+#define HeapTupleCopyBase(dest, src) \
+{ \
+	(dest)->t_xmin = (src)->t_xmin; \
+	(dest)->t_xmax = (src)->t_xmax; \
+}
+
+/*
+ * Set base values for tuple xids/multixacts to zero.  Used when visibility
+ * infromation is negligible or will be set later.
+ */
+#define HeapTupleSetZeroBase(tup) \
+{ \
+	(tup)->t_xmin = 0; \
+	(tup)->t_xmax = 0; \
+}
+
+/*
+ * Copy HeapTupleHeader xmin/xmax in raw way ???
+ */
+#define HeapTupleCopyHeaderXids(tup) \
+{ \
+	(tup)->t_xmin = (tup)->t_data->t_choice.t_heap.t_xmin; \
+	(tup)->t_xmax = (tup)->t_data->t_choice.t_heap.t_xmax; \
+}
+
+/*
+ * Macros for accessing "double xmax".  On pg_upgraded instances, it might
+ * happend that we can't fit new special area to the page.  But we still
+ * might neep to write xmax of tuples for updates and deletes.  The trick is
+ * that we actually don't need xmin field.  After pg_upgrade (wich implies
+ * restart) no insertions went to this page yet (otherwise special area could
+ * fit).  So, if tuple is visible (othewise it would be deleted), then it's
+ * visible for everybody.  Thus, t_xmin isn't needed.  Therefore, we can use
+ * both t_xmin and t_xmax to store 64-bit xmax.
+ *
+ * See heap_convert.c for details.
+ */
+#define HeapTupleHeaderGetDoubleXmax(tup) \
+	((TransactionId)(tup)->t_choice.t_heap.t_xmax + \
+		((TransactionId)(tup)->t_choice.t_heap.t_xmin << 32))
+
+#define HeapTupleHeaderSetDoubleXmax(tup, xid) \
+do { \
+	(tup)->t_choice.t_heap.t_xmax = (TransactionId) (xid) & 0xFFFFFFFF; \
+	(tup)->t_choice.t_heap.t_xmin = ((TransactionId) (xid) >> 32) & 0xFFFFFFFF; \
+} while (0)
+
+/*
+ * HeapTupleGetRawXmin returns the "raw" xmin field, which is the xid
  * originally used to insert the tuple.  However, the tuple might actually
  * be frozen (via HeapTupleHeaderSetXminFrozen) in which case the tuple's xmin
  * is visible to every snapshot.  Prior to PostgreSQL 9.4, we actually changed
  * the xmin to FrozenTransactionId, and that value may still be encountered
  * on disk.
  */
-#define HeapTupleHeaderGetRawXmin(tup) \
+#define HeapTupleGetRawXmin(tup)	((tup)->t_xmin)
+
+#define HeapTupleGetXmin(tup) \
 ( \
-	(tup)->t_choice.t_heap.t_xmin \
+	HeapTupleHeaderXminFrozen((tup)->t_data) ? \
+		FrozenTransactionId : HeapTupleGetRawXmin(tup) \
 )
 
-#define HeapTupleHeaderGetXmin(tup) \
+#define HeapTupleSetXmin(tup, xid) 	((tup)->t_xmin = (xid))
+
+#define HeapTupleHeaderSetXmin(page, tup) \
 ( \
-	HeapTupleHeaderXminFrozen(tup) ? \
-		FrozenTransactionId : HeapTupleHeaderGetRawXmin(tup) \
+	AssertMacro(!HeapPageIsDoubleXmax(page)), \
+	(tup)->t_data->t_choice.t_heap.t_xmin = NormalTransactionIdToShort(HeapPageGetSpecial(page)->pd_xid_base, (tup)->t_xmin) \
 )
 
-#define HeapTupleHeaderSetXmin(tup, xid) \
+#define ToastTupleHeaderSetXmin(page, tup) \
 ( \
-	(tup)->t_choice.t_heap.t_xmin = (xid) \
+	AssertMacro(!HeapPageIsDoubleXmax(page)), \
+	(tup)->t_data->t_choice.t_heap.t_xmin = NormalTransactionIdToShort(ToastPageGetSpecial(page)->pd_xid_base, (tup)->t_xmin) \
 )
 
 #define HeapTupleHeaderXminCommitted(tup) \
@@ -337,18 +395,6 @@ struct HeapTupleHeaderData
 	((tup)->t_infomask & (HEAP_XMIN_FROZEN)) == HEAP_XMIN_FROZEN \
 )
 
-#define HeapTupleHeaderSetXminCommitted(tup) \
-( \
-	AssertMacro(!HeapTupleHeaderXminInvalid(tup)), \
-	((tup)->t_infomask |= HEAP_XMIN_COMMITTED) \
-)
-
-#define HeapTupleHeaderSetXminInvalid(tup) \
-( \
-	AssertMacro(!HeapTupleHeaderXminCommitted(tup)), \
-	((tup)->t_infomask |= HEAP_XMIN_INVALID) \
-)
-
 #define HeapTupleHeaderSetXminFrozen(tup) \
 ( \
 	AssertMacro(!HeapTupleHeaderXminInvalid(tup)), \
@@ -362,30 +408,67 @@ struct HeapTupleHeaderData
  * to resolve the MultiXactId if necessary.  This might involve multixact I/O,
  * so it should only be used if absolutely necessary.
  */
-#define HeapTupleHeaderGetUpdateXid(tup) \
+#define HeapTupleGetUpdateXidAny(tup) \
 ( \
-	(!((tup)->t_infomask & HEAP_XMAX_INVALID) && \
-	 ((tup)->t_infomask & HEAP_XMAX_IS_MULTI) && \
-	 !((tup)->t_infomask & HEAP_XMAX_LOCK_ONLY)) ? \
+	(!((tup)->t_data->t_infomask & HEAP_XMAX_INVALID) && \
+	 ((tup)->t_data->t_infomask & HEAP_XMAX_IS_MULTI) && \
+	 !((tup)->t_data->t_infomask & HEAP_XMAX_LOCK_ONLY)) ? \
 		HeapTupleGetUpdateXid(tup) \
 	: \
-		HeapTupleHeaderGetRawXmax(tup) \
+		HeapTupleGetRawXmax(tup) \
 )
 
-#define HeapTupleHeaderGetRawXmax(tup) \
+#define HeapTupleGetRawXmax(tup)  ((tup)->t_xmax)
+
+#define HeapTupleHeaderGetRawXmax(page, tup) \
 ( \
-	(tup)->t_choice.t_heap.t_xmax \
+	HeapPageIsDoubleXmax(page) ? \
+	HeapTupleHeaderGetDoubleXmax(tup) : \
+	ShortTransactionIdToNormal( \
+		((tup)->t_infomask & HEAP_XMAX_IS_MULTI) ? HeapPageGetSpecial(page)->pd_multi_base : HeapPageGetSpecial(page)->pd_xid_base, \
+		(tup)->t_choice.t_heap.t_xmax) \
 )
 
-#define HeapTupleHeaderSetXmax(tup, xid) \
+#define ToastTupleHeaderGetRawXmax(page, tup) \
 ( \
-	(tup)->t_choice.t_heap.t_xmax = (xid) \
+	HeapPageIsDoubleXmax(page) ? \
+	HeapTupleHeaderGetDoubleXmax(tup) : \
+	ShortTransactionIdToNormal( \
+		ToastPageGetSpecial(page)->pd_xid_base, \
+		(tup)->t_choice.t_heap.t_xmax) \
 )
 
+#define HeapTupleSetXmax(tup, xid) \
+do { \
+	(tup)->t_xmax = (xid); \
+} while (0)
+
+#define HeapTupleHeaderSetXmax(page, tup) \
+do { \
+	if (HeapPageIsDoubleXmax(page)) \
+		HeapTupleHeaderSetDoubleXmax((tup)->t_data, (tup)->t_xmax); \
+	else \
+		(tup)->t_data->t_choice.t_heap.t_xmax = \
+			NormalTransactionIdToShort( \
+				((tup)->t_data->t_infomask & HEAP_XMAX_IS_MULTI) ? HeapPageGetSpecial(page)->pd_multi_base : HeapPageGetSpecial(page)->pd_xid_base, \
+				((tup)->t_xmax)); \
+} while (0)
+
+#define ToastTupleHeaderSetXmax(page, tup) \
+do { \
+	if (HeapPageIsDoubleXmax(page)) \
+		HeapTupleHeaderSetDoubleXmax((tup)->t_data, (tup)->t_xmax); \
+	else \
+		(tup)->t_data->t_choice.t_heap.t_xmax = \
+			NormalTransactionIdToShort( \
+				ToastPageGetSpecial(page)->pd_xid_base, \
+				((tup)->t_xmax)); \
+} while (0)
+
 /*
  * HeapTupleHeaderGetRawCommandId will give you what's in the header whether
- * it is useful or not.  Most code should use HeapTupleHeaderGetCmin or
- * HeapTupleHeaderGetCmax instead, but note that those Assert that you can
+ * it is useful or not.  Most code should use HeapTupleGetCmin or
+ * HeapTupleGetCmax instead, but note that those Assert that you can
  * get a legitimate result, ie you are in the originating transaction!
  */
 #define HeapTupleHeaderGetRawCommandId(tup) \
@@ -555,8 +638,16 @@ do { \
  * an otherwise-empty page can indeed hold a tuple of this size.  Because
  * ItemIds and tuples have different alignment requirements, don't assume that
  * you can, say, fit 2 tuples of size MaxHeapTupleSize/2 on the same page.
+ *
+ * On shift to 64-bit XIDs MaxHeapTupleSize decreased by sizeof(HeapPageSpecialData).
+ * Extant tuples with length over new MaxHeapTupleSize are inherited on DoubleXmax
+ * pages. They could be read, but can not be updated unless their length decreases
+ * to fit MaxHeapTupleSize. Vacuum full will also copy these double xmax pages
+ * without change.
  */
-#define MaxHeapTupleSize  (BLCKSZ - MAXALIGN(SizeOfPageHeaderData + sizeof(ItemIdData)))
+
+#define MaxHeapTupleSize  (BLCKSZ - MAXALIGN(SizeOfPageHeaderData + sizeof(ItemIdData)) - MAXALIGN(sizeof(HeapPageSpecialData)))
+#define MaxHeapTupleSize_32  (BLCKSZ - MAXALIGN(SizeOfPageHeaderData + sizeof(ItemIdData)))
 #define MinHeapTupleSize  MAXALIGN(SizeofHeapTupleHeader)
 
 /*
@@ -690,6 +781,76 @@ struct MinimalTupleData
 #define HeapTupleClearHeapOnly(tuple) \
 		HeapTupleHeaderClearHeapOnly((tuple)->t_data)
 
+static inline void
+HeapTupleCopyXminFromPage(HeapTuple tup, void *page, bool is_toast)
+{
+	TransactionId			base;
+	ShortTransactionId		xmin;	/* short xmin from tuple header */
+
+	if (HeapTupleHeaderXminFrozen(tup->t_data))
+	{
+		tup->t_xmin = FrozenTransactionId;
+		return;
+	}
+
+	xmin = tup->t_data->t_choice.t_heap.t_xmin;
+
+	if (!TransactionIdIsNormal(xmin))
+		base = 0;
+	else if (is_toast)
+		base = ToastPageGetSpecial(page)->pd_xid_base;
+	else
+		base = HeapPageGetSpecial(page)->pd_xid_base;
+
+	tup->t_xmin = ShortTransactionIdToNormal(base, xmin);
+}
+
+static inline void
+HeapTupleCopyXmaxFromPage(HeapTuple tup, void *page, bool is_toast)
+{
+	TransactionId			base;
+	ShortTransactionId		xmax; /* short xmax from tuple header */
+
+	xmax = tup->t_data->t_choice.t_heap.t_xmax;
+
+	if (!TransactionIdIsNormal(xmax))
+		base = 0;
+	else if (is_toast)
+		/*
+		 * Toast page is not expected to have multixacts in chunks and
+		 * has shorter special.
+		 */
+		base = ToastPageGetSpecial(page)->pd_xid_base;
+	else if (tup->t_data->t_infomask & HEAP_XMAX_IS_MULTI)
+		base = HeapPageGetSpecial(page)->pd_multi_base;
+	else
+		base = HeapPageGetSpecial(page)->pd_xid_base;
+
+	tup->t_xmax = ShortTransactionIdToNormal(base, xmax);
+}
+
+/*
+ * Copy base values for xid and multixacts from page to heap tuple.  Should be
+ * called each time tuple is read from page.  Otherwise, it would be impossible
+ * to correctly read tuple xmin and xmax.
+ */
+static inline void
+HeapTupleCopyBaseFromPage(HeapTuple tup, void *page, bool is_toast)
+{
+	if (HeapPageIsDoubleXmax(page))
+	{
+		/*
+		 * On double xmax pages, xmax is extracted from tuple header.
+		 */
+		tup->t_xmin = FrozenTransactionId;
+		tup->t_xmax = HeapTupleHeaderGetDoubleXmax(tup->t_data);
+		return;
+	}
+
+	HeapTupleCopyXminFromPage(tup, page, is_toast);
+	HeapTupleCopyXmaxFromPage(tup, page, is_toast);
+}
+
 /* prototypes for functions in common/heaptuple.c */
 extern Size heap_compute_data_size(TupleDesc tupleDesc,
 								   Datum *values, bool *isnull);
diff --git a/src/include/access/multixact.h b/src/include/access/multixact.h
index a5600a320a..a325693b3d 100644
--- a/src/include/access/multixact.h
+++ b/src/include/access/multixact.h
@@ -18,16 +18,16 @@
 
 /*
  * The first two MultiXactId values are reserved to store the truncation Xid
- * and epoch of the first segment, so we start assigning multixact values from
+ * and base of the first segment, so we start assigning multixact values from
  * 2.
  */
-#define InvalidMultiXactId	((MultiXactId) 0)
-#define FirstMultiXactId	((MultiXactId) 1)
-#define MaxMultiXactId		((MultiXactId) 0xFFFFFFFF)
+#define InvalidMultiXactId	UINT64CONST(0)
+#define FirstMultiXactId	UINT64CONST(1)
+#define MaxMultiXactId		UINT64CONST(0xFFFFFFFFFFFFFFFF)
 
 #define MultiXactIdIsValid(multi) ((multi) != InvalidMultiXactId)
 
-#define MaxMultiXactOffset	((MultiXactOffset) 0xFFFFFFFF)
+#define MaxMultiXactOffset	UINT64CONST(0xFFFFFFFFFFFFFFFF)
 
 /* Number of SLRU buffers to use for multixact */
 #define NUM_MULTIXACTOFFSET_BUFFERS		8
@@ -146,7 +146,6 @@ extern void MultiXactSetNextMXact(MultiXactId nextMulti,
 extern void MultiXactAdvanceNextMXact(MultiXactId minMulti,
 									  MultiXactOffset minMultiOffset);
 extern void MultiXactAdvanceOldest(MultiXactId oldestMulti, Oid oldestMultiDB);
-extern int	MultiXactMemberFreezeThreshold(void);
 
 extern void multixact_twophase_recover(TransactionId xid, uint16 info,
 									   void *recdata, uint32 len);
diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h
index 93f8267b48..dd229803ef 100644
--- a/src/include/access/nbtree.h
+++ b/src/include/access/nbtree.h
@@ -62,8 +62,10 @@ typedef uint16 BTCycleId;
 typedef struct BTPageOpaqueData
 {
 	BlockNumber btpo_prev;		/* left sibling, or P_NONE if leftmost */
+	/* ... or next transaction ID (lower part) */
 	BlockNumber btpo_next;		/* right sibling, or P_NONE if rightmost */
 	uint32		btpo_level;		/* tree level --- zero for leaf pages */
+	/* ... or next transaction ID (lower part) */
 	uint16		btpo_flags;		/* flag bits, see below */
 	BTCycleId	btpo_cycleid;	/* vacuum cycle ID of latest split */
 } BTPageOpaqueData;
@@ -92,6 +94,14 @@ typedef BTPageOpaqueData *BTPageOpaque;
  */
 #define MAX_BT_CYCLE_ID		0xFF7F
 
+/* Macros for access xact */
+#define BTP_GET_XACT(opaque) (((uint64) ((BTPageOpaque) opaque)->btpo_prev << 32) | \
+							   (uint64) ((BTPageOpaque) opaque)->btpo_level)
+#define BTP_SET_XACT(opaque, xact) \
+do { \
+	((BTPageOpaque) opaque)->btpo_prev = (uint32) (xact >> 32); \
+	((BTPageOpaque) opaque)->btpo_level = (uint32) xact; \
+} while (0)
 
 /*
  * The Meta page is always the first page in the btree index.
diff --git a/src/include/access/rewriteheap.h b/src/include/access/rewriteheap.h
index 353cbb2924..224c1e264a 100644
--- a/src/include/access/rewriteheap.h
+++ b/src/include/access/rewriteheap.h
@@ -51,7 +51,7 @@ typedef struct LogicalRewriteMappingData
  * 6) xid of the xact performing the mapping
  * ---
  */
-#define LOGICAL_REWRITE_FORMAT "map-%x-%x-%X_%X-%x-%x"
-extern void CheckPointLogicalRewriteHeap(void);
+#define LOGICAL_REWRITE_FORMAT "map-%x-%x-%X_%X-%x_%x-%x_%x"
+extern void	CheckPointLogicalRewriteHeap(void);
 
 #endif							/* REWRITE_HEAP_H */
diff --git a/src/include/access/rmgrlist.h b/src/include/access/rmgrlist.h
index 9a74721c97..bf748ea6cb 100644
--- a/src/include/access/rmgrlist.h
+++ b/src/include/access/rmgrlist.h
@@ -47,3 +47,4 @@ PG_RMGR(RM_COMMIT_TS_ID, "CommitTs", commit_ts_redo, commit_ts_desc, commit_ts_i
 PG_RMGR(RM_REPLORIGIN_ID, "ReplicationOrigin", replorigin_redo, replorigin_desc, replorigin_identify, NULL, NULL, NULL, NULL)
 PG_RMGR(RM_GENERIC_ID, "Generic", generic_redo, generic_desc, generic_identify, NULL, NULL, generic_mask, NULL)
 PG_RMGR(RM_LOGICALMSG_ID, "LogicalMessage", logicalmsg_redo, logicalmsg_desc, logicalmsg_identify, NULL, NULL, NULL, logicalmsg_decode)
+PG_RMGR(RM_HEAP3_ID, "Heap3", heap3_redo, heap3_desc, heap3_identify, NULL, NULL, heap_mask, NULL)
diff --git a/src/include/access/slru.h b/src/include/access/slru.h
index 4f5a324da2..767854419d 100644
--- a/src/include/access/slru.h
+++ b/src/include/access/slru.h
@@ -21,15 +21,7 @@
 /*
  * Define SLRU segment size.  A page is the same BLCKSZ as is used everywhere
  * else in Postgres.  The segment size can be chosen somewhat arbitrarily;
- * we make it 32 pages by default, or 256Kb, i.e. 1M transactions for CLOG
- * or 64K transactions for SUBTRANS.
- *
- * Note: because TransactionIds are 32 bits and wrap around at 0xFFFFFFFF,
- * page numbering also wraps around at 0xFFFFFFFF/xxxx_XACTS_PER_PAGE (where
- * xxxx is CLOG or SUBTRANS, respectively), and segment numbering at
- * 0xFFFFFFFF/xxxx_XACTS_PER_PAGE/SLRU_PAGES_PER_SEGMENT.  We need
- * take no explicit notice of that fact in slru.c, except when comparing
- * segment and page numbers in SimpleLruTruncate (see PagePrecedes()).
+ * we make it 32 pages by default.
  */
 #define SLRU_PAGES_PER_SEGMENT	32
 
diff --git a/src/include/access/tableam.h b/src/include/access/tableam.h
index 9df4e7cb0a..978ae2c03a 100644
--- a/src/include/access/tableam.h
+++ b/src/include/access/tableam.h
@@ -118,7 +118,7 @@ typedef enum TM_Result
  * cmax is the outdating command's CID, but only when the failure code is
  * TM_SelfModified (i.e., something in the current transaction outdated the
  * tuple); otherwise cmax is zero.  (We make this restriction because
- * HeapTupleHeaderGetCmax doesn't work for tuples outdated in other
+ * HeapTupleGetCmax doesn't work for tuples outdated in other
  * transactions.)
  */
 typedef struct TM_FailureData
diff --git a/src/include/access/transam.h b/src/include/access/transam.h
index 775471d2a7..e7cf1206df 100644
--- a/src/include/access/transam.h
+++ b/src/include/access/transam.h
@@ -17,6 +17,10 @@
 #include "access/xlogdefs.h"
 
 
+#ifndef FRONTEND
+#include "utils/elog.h"
+#endif
+
 /* ----------------
  *		Special transaction ID values
  *
@@ -28,11 +32,12 @@
  * Note: if you need to change it, you must change pg_class.h as well.
  * ----------------
  */
-#define InvalidTransactionId		((TransactionId) 0)
-#define BootstrapTransactionId		((TransactionId) 1)
-#define FrozenTransactionId			((TransactionId) 2)
-#define FirstNormalTransactionId	((TransactionId) 3)
-#define MaxTransactionId			((TransactionId) 0xFFFFFFFF)
+#define InvalidTransactionId		UINT64CONST(0)
+#define BootstrapTransactionId		UINT64CONST(1)
+#define FrozenTransactionId			UINT64CONST(2)
+#define FirstNormalTransactionId	UINT64CONST(3)
+#define MaxTransactionId			UINT64CONST(0xFFFFFFFFFFFFFFFF)
+#define MaxShortTransactionId		((TransactionId) 0x7FFFFFFF)
 
 /* ----------------
  *		transaction ID manipulation macros
@@ -44,17 +49,48 @@
 #define TransactionIdStore(xid, dest)	(*(dest) = (xid))
 #define StoreInvalidTransactionId(dest) (*(dest) = InvalidTransactionId)
 
-#define EpochFromFullTransactionId(x)	((uint32) ((x).value >> 32))
-#define XidFromFullTransactionId(x)		((uint32) (x).value)
-#define U64FromFullTransactionId(x)		((x).value)
+/*
+ * Convert short xid from/to full xid.  Assertion should fail if we full xid
+ * doesn't fit to xid base.
+ */
+static inline TransactionId
+ShortTransactionIdToNormal(TransactionId base, ShortTransactionId xid)
+{
+	if (!TransactionIdIsNormal(xid))
+		return (TransactionId) xid;
+
+#ifndef FRONTEND
+	/* xid + base should not overflow TransactionId */
+	Assert(xid + base >= base);
+#endif
+
+	return (TransactionId) (xid + base);
+}
+
+static inline ShortTransactionId
+NormalTransactionIdToShort(TransactionId base, TransactionId xid)
+{
+	if (!TransactionIdIsNormal(xid))
+		return (ShortTransactionId) (xid);
+
+#ifndef FRONTEND
+	/* xid should fit ShortTransactionId */
+	Assert(xid >= base + FirstNormalTransactionId &&
+		   xid <= base + MaxShortTransactionId);
+#endif
+
+	return (ShortTransactionId) (xid - base);
+}
+
+#define XidFromFullTransactionId(x)		((x).value)
 #define FullTransactionIdEquals(a, b)	((a).value == (b).value)
 #define FullTransactionIdPrecedes(a, b)	((a).value < (b).value)
 #define FullTransactionIdPrecedesOrEquals(a, b) ((a).value <= (b).value)
 #define FullTransactionIdFollows(a, b) ((a).value > (b).value)
 #define FullTransactionIdFollowsOrEquals(a, b) ((a).value >= (b).value)
 #define FullTransactionIdIsValid(x)		TransactionIdIsValid(XidFromFullTransactionId(x))
-#define InvalidFullTransactionId		FullTransactionIdFromEpochAndXid(0, InvalidTransactionId)
-#define FirstNormalFullTransactionId	FullTransactionIdFromEpochAndXid(0, FirstNormalTransactionId)
+#define InvalidFullTransactionId		FullTransactionIdFromXid(InvalidTransactionId)
+#define FirstNormalFullTransactionId	FullTransactionIdFromXid(FirstNormalTransactionId)
 #define FullTransactionIdIsNormal(x)	FullTransactionIdFollowsOrEquals(x, FirstNormalFullTransactionId)
 
 /*
@@ -68,21 +104,11 @@ typedef struct FullTransactionId
 } FullTransactionId;
 
 static inline FullTransactionId
-FullTransactionIdFromEpochAndXid(uint32 epoch, TransactionId xid)
-{
-	FullTransactionId result;
-
-	result.value = ((uint64) epoch) << 32 | xid;
-
-	return result;
-}
-
-static inline FullTransactionId
-FullTransactionIdFromU64(uint64 value)
+FullTransactionIdFromXid(TransactionId xid)
 {
 	FullTransactionId result;
 
-	result.value = value;
+	result.value = xid;
 
 	return result;
 }
@@ -91,8 +117,7 @@ FullTransactionIdFromU64(uint64 value)
 #define TransactionIdAdvance(dest)	\
 	do { \
 		(dest)++; \
-		if ((dest) < FirstNormalTransactionId) \
-			(dest) = FirstNormalTransactionId; \
+		Assert(TransactionIdIsNormal(dest)); \
 	} while(0)
 
 /*
@@ -140,18 +165,19 @@ FullTransactionIdAdvance(FullTransactionId *dest)
 /* back up a transaction ID variable, handling wraparound correctly */
 #define TransactionIdRetreat(dest)	\
 	do { \
+		Assert(TransactionIdIsNormal(dest)); \
 		(dest)--; \
-	} while ((dest) < FirstNormalTransactionId)
+	} while(0)
 
 /* compare two XIDs already known to be normal; this is a macro for speed */
 #define NormalTransactionIdPrecedes(id1, id2) \
 	(AssertMacro(TransactionIdIsNormal(id1) && TransactionIdIsNormal(id2)), \
-	(int32) ((id1) - (id2)) < 0)
+	(int64) ((id1) - (id2)) < 0)
 
 /* compare two XIDs already known to be normal; this is a macro for speed */
 #define NormalTransactionIdFollows(id1, id2) \
 	(AssertMacro(TransactionIdIsNormal(id1) && TransactionIdIsNormal(id2)), \
-	(int32) ((id1) - (id2)) > 0)
+	(int64) ((id1) - (id2)) > 0)
 
 /* ----------
  *		Object ID (OID) zero is InvalidOid.
@@ -221,9 +247,6 @@ typedef struct VariableCacheData
 
 	TransactionId oldestXid;	/* cluster-wide minimum datfrozenxid */
 	TransactionId xidVacLimit;	/* start forcing autovacuums here */
-	TransactionId xidWarnLimit; /* start complaining here */
-	TransactionId xidStopLimit; /* refuse to advance nextXid beyond here */
-	TransactionId xidWrapLimit; /* where the world ends */
 	Oid			oldestXidDB;	/* database with minimum datfrozenxid */
 
 	/*
@@ -276,10 +299,6 @@ extern bool TransactionIdDidAbort(TransactionId transactionId);
 extern void TransactionIdCommitTree(TransactionId xid, int nxids, TransactionId *xids);
 extern void TransactionIdAsyncCommitTree(TransactionId xid, int nxids, TransactionId *xids, XLogRecPtr lsn);
 extern void TransactionIdAbortTree(TransactionId xid, int nxids, TransactionId *xids);
-extern bool TransactionIdPrecedes(TransactionId id1, TransactionId id2);
-extern bool TransactionIdPrecedesOrEquals(TransactionId id1, TransactionId id2);
-extern bool TransactionIdFollows(TransactionId id1, TransactionId id2);
-extern bool TransactionIdFollowsOrEquals(TransactionId id1, TransactionId id2);
 extern TransactionId TransactionIdLatest(TransactionId mainxid,
 										 int nxids, const TransactionId *xids);
 extern XLogRecPtr TransactionIdGetCommitLSN(TransactionId xid);
@@ -319,7 +338,7 @@ ReadNextTransactionId(void)
 
 /* return transaction ID backed up by amount, handling wraparound correctly */
 static inline TransactionId
-TransactionIdRetreatedBy(TransactionId xid, uint32 amount)
+TransactionIdRetreatedBy(TransactionId xid, uint64 amount)
 {
 	xid -= amount;
 
diff --git a/src/include/access/tupmacs.h b/src/include/access/tupmacs.h
index 16c74a581e..6fe837f4d1 100644
--- a/src/include/access/tupmacs.h
+++ b/src/include/access/tupmacs.h
@@ -150,10 +150,11 @@
 	((attalign) == TYPALIGN_INT) ? INTALIGN(cur_offset) : \
 	 (((attalign) == TYPALIGN_CHAR) ? (uintptr_t) (cur_offset) : \
 	  (((attalign) == TYPALIGN_DOUBLE) ? DOUBLEALIGN(cur_offset) : \
+	   (((attalign) == TYPALIGN_XID) ? MAXALIGN(cur_offset) : \
 	   ( \
 			AssertMacro((attalign) == TYPALIGN_SHORT), \
 			SHORTALIGN(cur_offset) \
-	   ))) \
+	   )))) \
 )
 
 /*
diff --git a/src/include/access/xact.h b/src/include/access/xact.h
index 7d2b35213d..2245786f29 100644
--- a/src/include/access/xact.h
+++ b/src/include/access/xact.h
@@ -236,7 +236,7 @@ typedef struct xl_xact_xinfo
 	 * Commit records can be large, so copying large portions isn't
 	 * attractive.
 	 */
-	uint32		xinfo;
+	uint64		xinfo;
 } xl_xact_xinfo;
 
 typedef struct xl_xact_dbinfo
@@ -289,7 +289,12 @@ typedef struct xl_xact_invals
 
 typedef struct xl_xact_twophase
 {
-	TransactionId xid;
+	/*
+	 * TransactionId is split into 32-bit parts because xl_xact_twophase is
+	 * only int-aligned.
+	 */
+	uint32		xid_lo;
+	uint32		xid_hi;
 } xl_xact_twophase;
 
 typedef struct xl_xact_origin
@@ -308,7 +313,7 @@ typedef struct xl_xact_commit
 	/* xl_xact_relfilelocators follows if XINFO_HAS_RELFILELOCATORS */
 	/* xl_xact_stats_items follows if XINFO_HAS_DROPPED_STATS */
 	/* xl_xact_invals follows if XINFO_HAS_INVALS */
-	/* xl_xact_twophase follows if XINFO_HAS_TWOPHASE */
+	/* xl_xact_twophase follows if XINFO_HAS_TWOPHASE (xid is int-aligned!) */
 	/* twophase_gid follows if XINFO_HAS_GID. As a null-terminated string. */
 	/* xl_xact_origin follows if XINFO_HAS_ORIGIN, stored unaligned! */
 } xl_xact_commit;
@@ -324,7 +329,7 @@ typedef struct xl_xact_abort
 	/* xl_xact_relfilelocators follows if XINFO_HAS_RELFILELOCATORS */
 	/* xl_xact_stats_items follows if XINFO_HAS_DROPPED_STATS */
 	/* No invalidation messages needed. */
-	/* xl_xact_twophase follows if XINFO_HAS_TWOPHASE */
+	/* xl_xact_twophase follows if XINFO_HAS_TWOPHASE (xid is int-aligned!) */
 	/* twophase_gid follows if XINFO_HAS_GID. As a null-terminated string. */
 	/* xl_xact_origin follows if XINFO_HAS_ORIGIN, stored unaligned! */
 } xl_xact_abort;
diff --git a/src/include/access/xloginsert.h b/src/include/access/xloginsert.h
index c04f77b173..efedcd426a 100644
--- a/src/include/access/xloginsert.h
+++ b/src/include/access/xloginsert.h
@@ -37,6 +37,7 @@
 									 * will be skipped) */
 #define REGBUF_KEEP_DATA	0x10	/* include data even if a full-page image
 									 * is taken */
+#define REGBUF_CONVERTED	0x20	/* buffer had format convertion */
 
 /* prototypes for public functions in xloginsert.c: */
 extern void XLogBeginInsert(void);
diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h
index 5395f155aa..461ae545af 100644
--- a/src/include/access/xlogreader.h
+++ b/src/include/access/xlogreader.h
@@ -423,10 +423,6 @@ extern bool DecodeXLogRecord(XLogReaderState *state,
 #define XLogRecBlockImageApply(decoder, block_id)		\
 	((decoder)->record->blocks[block_id].apply_image)
 
-#ifndef FRONTEND
-extern FullTransactionId XLogRecGetFullXid(XLogReaderState *record);
-#endif
-
 extern bool RestoreBlockImage(XLogReaderState *record, uint8 block_id, char *page);
 extern char *XLogRecGetBlockData(XLogReaderState *record, uint8 block_id, Size *len);
 extern void XLogRecGetBlockTag(XLogReaderState *record, uint8 block_id,
diff --git a/src/include/access/xlogrecord.h b/src/include/access/xlogrecord.h
index 835151ec92..9eab0f53eb 100644
--- a/src/include/access/xlogrecord.h
+++ b/src/include/access/xlogrecord.h
@@ -41,18 +41,17 @@
 typedef struct XLogRecord
 {
 	uint32		xl_tot_len;		/* total len of entire record */
+	pg_crc32c	xl_crc;			/* CRC for this record */
 	TransactionId xl_xid;		/* xact id */
 	XLogRecPtr	xl_prev;		/* ptr to previous record in log */
 	uint8		xl_info;		/* flag bits, see below */
 	RmgrId		xl_rmid;		/* resource manager for this record */
-	/* 2 bytes of padding here, initialize to zero */
-	pg_crc32c	xl_crc;			/* CRC for this record */
 
 	/* XLogRecordBlockHeaders and XLogRecordDataHeader follow, no padding */
 
 } XLogRecord;
 
-#define SizeOfXLogRecord	(offsetof(XLogRecord, xl_crc) + sizeof(pg_crc32c))
+#define SizeOfXLogRecord	(offsetof(XLogRecord, xl_rmid) + sizeof(RmgrId))
 
 /*
  * The high 4 bits in xl_info may be used freely by rmgr. The
diff --git a/src/include/c.h b/src/include/c.h
index 863a16c6a6..1f9f587e45 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -75,6 +75,10 @@
 #include <libintl.h>
 #endif
 
+#if HAVE_INTTYPES_H
+#include "inttypes.h"
+#endif
+
 
 /* ----------------------------------------------------------------
  *				Section 1: compiler characteristics
@@ -595,19 +599,29 @@ typedef double float8;
 typedef Oid regproc;
 typedef regproc RegProcedure;
 
-typedef uint32 TransactionId;
+typedef uint64 TransactionId;
 
-typedef uint32 LocalTransactionId;
+extern bool TransactionIdPrecedes(TransactionId id1, TransactionId id2);
+extern bool TransactionIdPrecedesOrEquals(TransactionId id1, TransactionId id2);
+extern bool TransactionIdFollows(TransactionId id1, TransactionId id2);
+extern bool TransactionIdFollowsOrEquals(TransactionId id1, TransactionId id2);
 
-typedef uint32 SubTransactionId;
+typedef uint32 ShortTransactionId;
+typedef uint64 LocalTransactionId;
+typedef uint64 SubTransactionId;
 
-#define InvalidSubTransactionId		((SubTransactionId) 0)
-#define TopSubTransactionId			((SubTransactionId) 1)
+#define InvalidSubTransactionId        ((SubTransactionId) 0)
+#define TopSubTransactionId            ((SubTransactionId) 1)
 
 /* MultiXactId must be equivalent to TransactionId, to fit in t_xmax */
 typedef TransactionId MultiXactId;
 
-typedef uint32 MultiXactOffset;
+typedef uint64 MultiXactOffset;
+
+#define MAX_START_XID			UINT64CONST(0x3FFFFFFFFFFFFFFF)	/* 2^62 - 1 */
+#define StartTransactionIdIsValid(xid)		((xid) <= MAX_START_XID)
+#define StartMultiXactIdIsValid(mxid)		((mxid) <= MAX_START_XID)
+#define StartMultiXactOffsetIsValid(mxoff)	((mxoff) <= MAX_START_XID)
 
 typedef uint32 CommandId;
 
@@ -792,7 +806,6 @@ typedef NameData *Name;
 /* we don't currently need wider versions of the other ALIGN macros */
 #define MAXALIGN64(LEN)			TYPEALIGN64(MAXIMUM_ALIGNOF, (LEN))
 
-
 /* ----------------------------------------------------------------
  *				Section 6:	assertions
  * ----------------------------------------------------------------
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index c1d2e872b3..ff9de419b7 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -53,6 +53,7 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202207081
+/* XXX: should de changed to actual version on commit */
+#define CATALOG_VERSION_NO	999999999
 
 #endif
diff --git a/src/include/catalog/pg_amproc.dat b/src/include/catalog/pg_amproc.dat
index 4cc129bebd..4f20977635 100644
--- a/src/include/catalog/pg_amproc.dat
+++ b/src/include/catalog/pg_amproc.dat
@@ -403,9 +403,9 @@
   amprocrighttype => 'bytea', amprocnum => '2',
   amproc => 'hashvarlenaextended' },
 { amprocfamily => 'hash/xid_ops', amproclefttype => 'xid',
-  amprocrighttype => 'xid', amprocnum => '1', amproc => 'hashint4' },
+  amprocrighttype => 'xid', amprocnum => '1', amproc => 'hashint8' },
 { amprocfamily => 'hash/xid_ops', amproclefttype => 'xid',
-  amprocrighttype => 'xid', amprocnum => '2', amproc => 'hashint4extended' },
+  amprocrighttype => 'xid', amprocnum => '2', amproc => 'hashint8extended' },
 { amprocfamily => 'hash/xid8_ops', amproclefttype => 'xid8',
   amprocrighttype => 'xid8', amprocnum => '1', amproc => 'hashint8' },
 { amprocfamily => 'hash/xid8_ops', amproclefttype => 'xid8',
diff --git a/src/include/catalog/pg_control.h b/src/include/catalog/pg_control.h
index 06368e2366..ab02a0896f 100644
--- a/src/include/catalog/pg_control.h
+++ b/src/include/catalog/pg_control.h
@@ -247,4 +247,10 @@ typedef struct ControlFileData
  */
 #define PG_CONTROL_FILE_SIZE		8192
 
+#define CONTROLFILE_GET_OLDEDITION(control)	\
+	((control)->pg_old_version >> 16)
+
+#define CONTROLFILE_SET_OLDEDITION(control, v)	\
+	(control)->pg_old_version = ((v) << 16)
+
 #endif							/* PG_CONTROL_H */
diff --git a/src/include/catalog/pg_operator.dat b/src/include/catalog/pg_operator.dat
index bc5f8213f3..912ab48ecf 100644
--- a/src/include/catalog/pg_operator.dat
+++ b/src/include/catalog/pg_operator.dat
@@ -183,16 +183,16 @@
   oprresult => 'bool', oprcom => '=(xid,xid)', oprnegate => '<>(xid,xid)',
   oprcode => 'xideq', oprrest => 'eqsel', oprjoin => 'eqjoinsel' },
 { oid => '353', descr => 'equal',
-  oprname => '=', oprleft => 'xid', oprright => 'int4', oprresult => 'bool',
-  oprnegate => '<>(xid,int4)', oprcode => 'xideqint4', oprrest => 'eqsel',
+  oprname => '=', oprleft => 'xid', oprright => 'int8', oprresult => 'bool',
+  oprnegate => '<>(xid,int8)', oprcode => 'xideqint8', oprrest => 'eqsel',
   oprjoin => 'eqjoinsel' },
 { oid => '3315', descr => 'not equal',
   oprname => '<>', oprleft => 'xid', oprright => 'xid', oprresult => 'bool',
   oprcom => '<>(xid,xid)', oprnegate => '=(xid,xid)', oprcode => 'xidneq',
   oprrest => 'neqsel', oprjoin => 'neqjoinsel' },
 { oid => '3316', descr => 'not equal',
-  oprname => '<>', oprleft => 'xid', oprright => 'int4', oprresult => 'bool',
-  oprnegate => '=(xid,int4)', oprcode => 'xidneqint4', oprrest => 'neqsel',
+  oprname => '<>', oprleft => 'xid', oprright => 'int8', oprresult => 'bool',
+  oprnegate => '=(xid,int8)', oprcode => 'xidneqint8', oprrest => 'neqsel',
   oprjoin => 'neqjoinsel' },
 { oid => '5068', descr => 'equal',
   oprname => '=', oprcanmerge => 't', oprcanhash => 't', oprleft => 'xid8',
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index 2e41f4d9e8..6e567f2594 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -2366,10 +2366,10 @@
 { oid => '1181',
   descr => 'age of a transaction ID, in transactions before current transaction',
   proname => 'age', provolatile => 's', proparallel => 'r',
-  prorettype => 'int4', proargtypes => 'xid', prosrc => 'xid_age' },
+  prorettype => 'int8', proargtypes => 'xid', prosrc => 'xid_age' },
 { oid => '3939',
   descr => 'age of a multi-transaction ID, in multi-transactions before current multi-transaction',
-  proname => 'mxid_age', provolatile => 's', prorettype => 'int4',
+  proname => 'mxid_age', provolatile => 's', prorettype => 'int8',
   proargtypes => 'xid', prosrc => 'mxid_age' },
 
 { oid => '1188',
@@ -2704,11 +2704,11 @@
   prosrc => 'bpcharlen' },
 
 { oid => '1319',
-  proname => 'xideqint4', proleakproof => 't', prorettype => 'bool',
-  proargtypes => 'xid int4', prosrc => 'xideq' },
+  proname => 'xideqint8', proleakproof => 't', prorettype => 'bool',
+  proargtypes => 'xid int8', prosrc => 'xideq' },
 { oid => '3309',
-  proname => 'xidneqint4', proleakproof => 't', prorettype => 'bool',
-  proargtypes => 'xid int4', prosrc => 'xidneq' },
+  proname => 'xidneqint8', proleakproof => 't', prorettype => 'bool',
+  proargtypes => 'xid int8', prosrc => 'xidneq' },
 
 { oid => '1326',
   proname => 'interval_div', prorettype => 'interval',
diff --git a/src/include/catalog/pg_type.dat b/src/include/catalog/pg_type.dat
index df45879463..9ecd608aa9 100644
--- a/src/include/catalog/pg_type.dat
+++ b/src/include/catalog/pg_type.dat
@@ -95,9 +95,9 @@
   typinput => 'tidin', typoutput => 'tidout', typreceive => 'tidrecv',
   typsend => 'tidsend', typalign => 's' },
 { oid => '28', array_type_oid => '1011', descr => 'transaction id',
-  typname => 'xid', typlen => '4', typbyval => 't', typcategory => 'U',
+  typname => 'xid', typlen => '8', typbyval => 'FLOAT8PASSBYVAL', typcategory => 'U',
   typinput => 'xidin', typoutput => 'xidout', typreceive => 'xidrecv',
-  typsend => 'xidsend', typalign => 'i' },
+  typsend => 'xidsend', typalign => 'x' },
 { oid => '29', array_type_oid => '1012',
   descr => 'command identifier type, sequence in transaction id',
   typname => 'cid', typlen => '4', typbyval => 't', typcategory => 'U',
diff --git a/src/include/catalog/pg_type.h b/src/include/catalog/pg_type.h
index 48a2559137..71f5f547f4 100644
--- a/src/include/catalog/pg_type.h
+++ b/src/include/catalog/pg_type.h
@@ -300,6 +300,11 @@ DECLARE_UNIQUE_INDEX(pg_type_typname_nsp_index, 2704, TypeNameNspIndexId, on pg_
 #define  TYPALIGN_SHORT			's' /* short alignment (typically 2 bytes) */
 #define  TYPALIGN_INT			'i' /* int alignment (typically 4 bytes) */
 #define  TYPALIGN_DOUBLE		'd' /* double alignment (often 8 bytes) */
+/*
+ * We need to use alignment sutable for 8-byte XID values.
+ * On system like AIX double alignment (4 bytes) is not enough.
+ */
+#define  TYPALIGN_XID			'x'
 
 #define  TYPSTORAGE_PLAIN		'p' /* type not prepared for toasting */
 #define  TYPSTORAGE_EXTERNAL	'e' /* toastable, don't try to compress */
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index f38e1148f9..134a0afca6 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -213,12 +213,12 @@ typedef enum VacOptValue
  */
 typedef struct VacuumParams
 {
-	bits32		options;		/* bitmask of VACOPT_* */
-	int			freeze_min_age; /* min freeze age, -1 to use default */
-	int			freeze_table_age;	/* age at which to scan whole table */
-	int			multixact_freeze_min_age;	/* min multixact freeze age, -1 to
+	bits32		options;		/* bitmask of VacuumOption */
+	int64		freeze_min_age; /* min freeze age, -1 to use default */
+	int64		freeze_table_age;	/* age at which to scan whole table */
+	int64		multixact_freeze_min_age;	/* min multixact freeze age, -1 to
 											 * use default */
-	int			multixact_freeze_table_age; /* multixact age at which to scan
+	int64		multixact_freeze_table_age; /* multixact age at which to scan
 											 * whole table */
 	bool		is_wraparound;	/* force a for-wraparound vacuum */
 	int			log_min_duration;	/* minimum execution threshold in ms at
@@ -252,12 +252,12 @@ typedef struct VacDeadItems
 
 /* GUC parameters */
 extern PGDLLIMPORT int default_statistics_target;	/* PGDLLIMPORT for PostGIS */
-extern PGDLLIMPORT int vacuum_freeze_min_age;
-extern PGDLLIMPORT int vacuum_freeze_table_age;
-extern PGDLLIMPORT int vacuum_multixact_freeze_min_age;
-extern PGDLLIMPORT int vacuum_multixact_freeze_table_age;
-extern PGDLLIMPORT int vacuum_failsafe_age;
-extern PGDLLIMPORT int vacuum_multixact_failsafe_age;
+extern PGDLLIMPORT int64 vacuum_freeze_min_age;
+extern PGDLLIMPORT int64 vacuum_freeze_table_age;
+extern PGDLLIMPORT int64 vacuum_multixact_freeze_min_age;
+extern PGDLLIMPORT int64 vacuum_multixact_freeze_table_age;
+extern PGDLLIMPORT int64 vacuum_failsafe_age;
+extern PGDLLIMPORT int64 vacuum_multixact_failsafe_age;
 
 /* Variables for cost-based parallel vacuum */
 extern PGDLLIMPORT pg_atomic_uint32 *VacuumSharedCostBalance;
@@ -287,9 +287,9 @@ extern void vac_update_relstats(Relation relation,
 								bool *minmulti_updated,
 								bool in_outer_xact);
 extern bool vacuum_set_xid_limits(Relation rel,
-								  int freeze_min_age, int freeze_table_age,
-								  int multixact_freeze_min_age,
-								  int multixact_freeze_table_age,
+								  int64 freeze_min_age, int64 freeze_table_age,
+								  int64 multixact_freeze_min_age,
+								  int64 multixact_freeze_table_age,
 								  TransactionId *oldestXmin,
 								  MultiXactId *oldestMxact,
 								  TransactionId *freezeLimit,
diff --git a/src/include/fmgr.h b/src/include/fmgr.h
index 5314b73705..be577c0b47 100644
--- a/src/include/fmgr.h
+++ b/src/include/fmgr.h
@@ -281,6 +281,7 @@ extern struct varlena *pg_detoast_datum_packed(struct varlena *datum);
 #define PG_GETARG_FLOAT4(n)  DatumGetFloat4(PG_GETARG_DATUM(n))
 #define PG_GETARG_FLOAT8(n)  DatumGetFloat8(PG_GETARG_DATUM(n))
 #define PG_GETARG_INT64(n)	 DatumGetInt64(PG_GETARG_DATUM(n))
+#define PG_GETARG_TRANSACTIONID(n)	DatumGetTransactionId(PG_GETARG_DATUM(n))
 /* use this if you want the raw, possibly-toasted input datum: */
 #define PG_GETARG_RAW_VARLENA_P(n)	((struct varlena *) PG_GETARG_POINTER(n))
 /* use this if you want the input datum de-toasted: */
@@ -367,6 +368,7 @@ extern struct varlena *pg_detoast_datum_packed(struct varlena *datum);
 #define PG_RETURN_FLOAT8(x)  return Float8GetDatum(x)
 #define PG_RETURN_INT64(x)	 return Int64GetDatum(x)
 #define PG_RETURN_UINT64(x)  return UInt64GetDatum(x)
+#define PG_RETURN_TRANSACTIONID(x)	return TransactionIdGetDatum(x)
 /* RETURN macros for other pass-by-ref types will typically look like this: */
 #define PG_RETURN_BYTEA_P(x)   PG_RETURN_POINTER(x)
 #define PG_RETURN_TEXT_P(x)    PG_RETURN_POINTER(x)
diff --git a/src/include/nodes/pg_list.h b/src/include/nodes/pg_list.h
index 66e70263b2..3c0de4f707 100644
--- a/src/include/nodes/pg_list.h
+++ b/src/include/nodes/pg_list.h
@@ -44,6 +44,7 @@ typedef union ListCell
 {
 	void	   *ptr_value;
 	int			int_value;
+	int64		int64_value;
 	Oid			oid_value;
 	TransactionId xid_value;
 } ListCell;
@@ -169,6 +170,7 @@ list_length(const List *l)
  */
 #define lfirst(lc)				((lc)->ptr_value)
 #define lfirst_int(lc)			((lc)->int_value)
+#define lfirst_int64(lc)		((lc)->int64_value)
 #define lfirst_oid(lc)			((lc)->oid_value)
 #define lfirst_xid(lc)			((lc)->xid_value)
 #define lfirst_node(type,lc)	castNode(type, lfirst(lc))
@@ -195,6 +197,7 @@ list_length(const List *l)
 
 #define llast(l)				lfirst(list_last_cell(l))
 #define llast_int(l)			lfirst_int(list_last_cell(l))
+#define llast_int64(l)			lfirst_int64(list_last_cell(l))
 #define llast_oid(l)			lfirst_oid(list_last_cell(l))
 #define llast_xid(l)			lfirst_xid(list_last_cell(l))
 #define llast_node(type,l)		castNode(type, llast(l))
@@ -557,6 +560,7 @@ extern List *list_make5_impl(NodeTag t, ListCell datum1, ListCell datum2,
 
 extern pg_nodiscard List *lappend(List *list, void *datum);
 extern pg_nodiscard List *lappend_int(List *list, int datum);
+extern pg_nodiscard List *lappend_int64(List *list, int64 datum);
 extern pg_nodiscard List *lappend_oid(List *list, Oid datum);
 extern pg_nodiscard List *lappend_xid(List *list, TransactionId datum);
 
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index 7133c3dc66..992d554ab1 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -970,6 +970,9 @@
 # endif
 #endif
 
+/* Postgres Pro use 64bit xids */
+#undef XID_IS_64BIT
+
 /* Size of a WAL file block. This need have no particular relation to BLCKSZ.
    XLOG_BLCKSZ must be a power of 2, and if your system supports O_DIRECT I/O,
    XLOG_BLCKSZ must be a multiple of the alignment requirement for direct-I/O
diff --git a/src/include/postgres.h b/src/include/postgres.h
index 31358110dc..e8b4b1f9df 100644
--- a/src/include/postgres.h
+++ b/src/include/postgres.h
@@ -555,21 +555,21 @@ typedef struct NullableDatum
  *		Returns transaction identifier value of a datum.
  */
 
-#define DatumGetTransactionId(X) ((TransactionId) (X))
+#define DatumGetTransactionId(X) (DatumGetUInt64(X))
 
 /*
  * TransactionIdGetDatum
  *		Returns datum representation for a transaction identifier.
  */
 
-#define TransactionIdGetDatum(X) ((Datum) (X))
+#define TransactionIdGetDatum(X) (UInt64GetDatum(X))
 
 /*
  * MultiXactIdGetDatum
  *		Returns datum representation for a multixact identifier.
  */
 
-#define MultiXactIdGetDatum(X) ((Datum) (X))
+#define MultiXactIdGetDatum(X) (UInt64GetDatum(X))
 
 /*
  * DatumGetCommandId
diff --git a/src/include/postmaster/autovacuum.h b/src/include/postmaster/autovacuum.h
index 9d40fd6d54..03024361ea 100644
--- a/src/include/postmaster/autovacuum.h
+++ b/src/include/postmaster/autovacuum.h
@@ -37,8 +37,8 @@ extern PGDLLIMPORT int autovacuum_vac_ins_thresh;
 extern PGDLLIMPORT double autovacuum_vac_ins_scale;
 extern PGDLLIMPORT int autovacuum_anl_thresh;
 extern PGDLLIMPORT double autovacuum_anl_scale;
-extern PGDLLIMPORT int autovacuum_freeze_max_age;
-extern PGDLLIMPORT int autovacuum_multixact_freeze_max_age;
+extern PGDLLIMPORT int64 autovacuum_freeze_max_age;
+extern PGDLLIMPORT int64 autovacuum_multixact_freeze_max_age;
 extern PGDLLIMPORT double autovacuum_vac_cost_delay;
 extern PGDLLIMPORT int autovacuum_vac_cost_limit;
 
diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h
index aded5e8f7e..0c2e341ba9 100644
--- a/src/include/storage/buf_internals.h
+++ b/src/include/storage/buf_internals.h
@@ -40,10 +40,10 @@
  */
 #define BUF_REFCOUNT_ONE 1
 #define BUF_REFCOUNT_MASK ((1U << 18) - 1)
-#define BUF_USAGECOUNT_MASK 0x003C0000U
+#define BUF_USAGECOUNT_MASK 0x001C0000U
 #define BUF_USAGECOUNT_ONE (1U << 18)
 #define BUF_USAGECOUNT_SHIFT 18
-#define BUF_FLAG_MASK 0xFFC00000U
+#define BUF_FLAG_MASK 0xFFE00000U
 
 /* Get refcount and usagecount from buffer state */
 #define BUF_STATE_GET_REFCOUNT(state) ((state) & BUF_REFCOUNT_MASK)
@@ -55,6 +55,7 @@
  * Note: BM_TAG_VALID essentially means that there is a buffer hashtable
  * entry associated with the buffer's tag.
  */
+#define BM_CONVERTED			(1U << 21)	/* buffer were converted to 64xid */
 #define BM_LOCKED				(1U << 22)	/* buffer header is locked */
 #define BM_DIRTY				(1U << 23)	/* data needs writing */
 #define BM_VALID				(1U << 24)	/* data is valid */
diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h
index 7bcfaac272..17a6f682d2 100644
--- a/src/include/storage/bufmgr.h
+++ b/src/include/storage/bufmgr.h
@@ -229,6 +229,8 @@ extern void BufferGetTag(Buffer buffer, RelFileLocator *rlocator,
 						 ForkNumber *forknum, BlockNumber *blknum);
 
 extern void MarkBufferDirtyHint(Buffer buffer, bool buffer_std);
+extern void MarkBufferConverted(Buffer buffer, bool converted);
+extern bool IsBufferConverted(Buffer buffer);
 
 extern void UnlockBuffers(void);
 extern void LockBuffer(Buffer buffer, int mode);
@@ -251,6 +253,8 @@ extern void TestForOldSnapshot_impl(Snapshot snapshot, Relation relation);
 extern BufferAccessStrategy GetAccessStrategy(BufferAccessStrategyType btype);
 extern void FreeAccessStrategy(BufferAccessStrategy strategy);
 
+/* old tuple format support */
+extern void convert_page(Relation rel, Page orig_page, Buffer buf, BlockNumber blkno);
 
 /* inline functions */
 
diff --git a/src/include/storage/bufpage.h b/src/include/storage/bufpage.h
index e9f253f2c8..8342717a2a 100644
--- a/src/include/storage/bufpage.h
+++ b/src/include/storage/bufpage.h
@@ -14,10 +14,13 @@
 #ifndef BUFPAGE_H
 #define BUFPAGE_H
 
+#include "access/transam.h"
 #include "access/xlogdefs.h"
 #include "storage/block.h"
 #include "storage/item.h"
 #include "storage/off.h"
+#include "postgres.h"
+#include "utils/rel.h"
 
 /*
  * A postgres disk page is an abstraction layered on top of a postgres
@@ -159,12 +162,41 @@ typedef struct PageHeaderData
 	LocationIndex pd_upper;		/* offset to end of free space */
 	LocationIndex pd_special;	/* offset to start of special space */
 	uint16		pd_pagesize_version;
-	TransactionId pd_prune_xid; /* oldest prunable XID, or zero if none */
+	ShortTransactionId pd_prune_xid;	/* oldest prunable XID, or zero if
+										 * none */
 	ItemIdData	pd_linp[FLEXIBLE_ARRAY_MEMBER]; /* line pointer array */
 } PageHeaderData;
 
 typedef PageHeaderData *PageHeader;
 
+
+/*
+ * HeapPageSpecialData -- data that stored at the end of each heap page.
+ *
+ *		pd_xid_base - base value for transaction IDs on page
+ *		pd_multi_base - base value for multixact IDs on page
+ *
+ * pd_xid_base and pd_multi_base are base values for calculation of transaction
+ * identifiers from t_xmin and t_xmax in each heap tuple header on the page.
+ */
+typedef struct HeapPageSpecialData
+{
+	TransactionId pd_xid_base;	/* base value for transaction IDs on page */
+	TransactionId pd_multi_base;	/* base value for multixact IDs on page */
+}			HeapPageSpecialData;
+
+typedef HeapPageSpecialData *HeapPageSpecial;
+
+typedef struct ToastPageSpecialData
+{
+	TransactionId pd_xid_base;	/* base value for transaction IDs on page */
+}			ToastPageSpecialData;
+
+typedef ToastPageSpecialData *ToastPageSpecial;
+
+extern PGDLLIMPORT HeapPageSpecial heapDoubleXmaxSpecial;
+extern PGDLLIMPORT ToastPageSpecial toastDoubleXmaxSpecial;
+
 /*
  * pd_flags contains the following flag bits.  Undefined bits are initialized
  * to zero and may be used in the future.
@@ -196,7 +228,7 @@ typedef PageHeaderData *PageHeader;
  * As of Release 9.3, the checksum version must also be considered when
  * handling pages.
  */
-#define PG_PAGE_LAYOUT_VERSION		4
+#define PG_PAGE_LAYOUT_VERSION		5
 #define PG_DATA_CHECKSUM_VERSION	1
 
 /* ----------------------------------------------------------------
@@ -389,16 +421,178 @@ PageValidateSpecialPointer(Page page)
 #define PageClearAllVisible(page) \
 	(((PageHeader) (page))->pd_flags &= ~PD_ALL_VISIBLE)
 
-#define PageSetPrunable(page, xid) \
-do { \
-	Assert(TransactionIdIsNormal(xid)); \
-	if (!TransactionIdIsValid(((PageHeader) (page))->pd_prune_xid) || \
-		TransactionIdPrecedes(xid, ((PageHeader) (page))->pd_prune_xid)) \
-		((PageHeader) (page))->pd_prune_xid = (xid); \
-} while (0)
-#define PageClearPrunable(page) \
-	(((PageHeader) (page))->pd_prune_xid = InvalidTransactionId)
+/*
+ * Check if page is in "double xmax" format.
+ */
+static inline bool
+HeapPageIsDoubleXmax(Page page)
+{
+	return ((PageHeader) (page))->pd_special == BLCKSZ;
+}
+
+/*
+ * Get pointer to HeapPageSpecialData.
+ *
+ * Can be used for non-consistent reads from non-locked pages.
+ *
+ * Return doubleXmaxSpecial when pd_special == BLCKSZ (i.e. "double xmax"
+ * format).
+ */
+static inline HeapPageSpecial
+HeapPageGetSpecialNoAssert(Page page)
+{
+	if (HeapPageIsDoubleXmax(page))
+		return heapDoubleXmaxSpecial;
+
+	return (HeapPageSpecial) ((char *) page +
+							  ((PageHeader) page)->pd_special);
+}
+
+/*
+ * Get pointer to ToastPageSpecialData.
+ *
+ * Can be used for non-consistent reads from non-locked pages.
+ *
+ * Return doubleXmaxSpecial when pd_special == BLCKSZ (i.e. "double xmax"
+ * format).
+ */
+static inline ToastPageSpecial
+ToastPageGetSpecialNoAssert(Page page)
+{
+	if (HeapPageIsDoubleXmax(page))
+		return toastDoubleXmaxSpecial;
+
+	return (ToastPageSpecial) ((char *) page +
+							   ((PageHeader) page)->pd_special);
+}
+
+/*
+ * Wrapper for HeapPageGetSpecialNoAssert for general use.
+ */
+static inline HeapPageSpecial
+HeapPageGetSpecial(Page page)
+{
+	if (HeapPageIsDoubleXmax(page))
+		return heapDoubleXmaxSpecial;
+
+	Assert(((PageHeader) page)->pd_special ==
+		   BLCKSZ - MAXALIGN(sizeof(HeapPageSpecialData)));
+
+	return (HeapPageSpecial) ((char *) page +
+							  ((PageHeader) page)->pd_special);
+}
+
+/*
+ * Wrapper for ToastPageGetSpecialNoAssert for general use.
+ */
+static inline ToastPageSpecial
+ToastPageGetSpecial(Page page)
+{
+	if (HeapPageIsDoubleXmax(page))
+		return toastDoubleXmaxSpecial;
+
+	Assert(((PageHeader) page)->pd_special ==
+		   BLCKSZ - MAXALIGN(sizeof(ToastPageSpecialData)));
+
+	return (ToastPageSpecial) ((char *) page +
+							   ((PageHeader) page)->pd_special);
+}
+
+/*
+ * Set pd_prune_xid.
+ */
+static inline void
+HeapPageSetPruneXid(Page page, TransactionId xid, bool is_toast)
+{
+	TransactionId	base;
+
+	if (HeapPageIsDoubleXmax(page))
+		return;
+
+	if (!TransactionIdIsNormal(xid))
+	{
+		((PageHeader) (page))->pd_prune_xid = xid;
+		return;
+	}
+
+	base = is_toast ? ToastPageGetSpecial(page)->pd_xid_base :
+					  HeapPageGetSpecial(page)->pd_xid_base;
+
+	((PageHeader) (page))->pd_prune_xid = NormalTransactionIdToShort(base, xid);
+	Assert(((PageHeader) (page))->pd_prune_xid <= MaxShortTransactionId);
+}
+
+static inline void
+ToastPageSetPruneXid(Page page, TransactionId xid)
+{
+	if (HeapPageIsDoubleXmax(page))
+		return;
+
+	if (!TransactionIdIsNormal(xid))
+	{
+		((PageHeader) (page))->pd_prune_xid = xid;
+		return;
+	}
+
+	((PageHeader) (page))->pd_prune_xid =
+		NormalTransactionIdToShort(ToastPageGetSpecial(page)->pd_xid_base, (xid));
+
+	Assert(((PageHeader) (page))->pd_prune_xid <= MaxShortTransactionId);
+}
+
+/*
+ * Get pd_prune_xid from locked page.
+ */
+static inline TransactionId
+HeapPageGetPruneXid(Page page, bool is_toast)
+{
+	TransactionId	base;
+
+	if (HeapPageIsDoubleXmax(page))
+		return ((PageHeader) (page))->pd_prune_xid;
+
+	base = is_toast ? ToastPageGetSpecial(page)->pd_xid_base :
+					  HeapPageGetSpecial(page)->pd_xid_base;
+
+	return ShortTransactionIdToNormal(base,
+									  ((PageHeader) (page))->pd_prune_xid);
+}
+
+static inline void
+PageSetPrunable(Page page, TransactionId xid, bool is_toast)
+{
+	TransactionId	prune_xid;
+
+	Assert(TransactionIdIsNormal(xid));
+
+	if (HeapPageIsDoubleXmax(page))
+		return;
+
+	prune_xid = HeapPageGetPruneXid(page, is_toast);
+	if ((!TransactionIdIsValid(prune_xid) ||
+		TransactionIdPrecedes(xid, prune_xid)))
+	{
+		HeapPageSetPruneXid(page, xid, is_toast);
+	}
+}
+
+/*
+ * Get pd_prune_xid from non-locked page.  May return invalid value, but doen't
+ * causes assert failures.
+ */
+static inline TransactionId
+HeapPageGetPruneXidNoAssert(Page page, bool is_toast)
+{
+	TransactionId	base;
 
+	if (HeapPageIsDoubleXmax(page))
+		return ((PageHeader) (page))->pd_prune_xid;
+
+	base = is_toast ? ToastPageGetSpecialNoAssert(page)->pd_xid_base :
+					  HeapPageGetSpecialNoAssert(page)->pd_xid_base;
+	return ShortTransactionIdToNormal(base,
+									  ((PageHeader) (page))->pd_prune_xid);
+}
 
 /* ----------------------------------------------------------------
  *		extern declarations
@@ -432,6 +626,21 @@ do { \
 StaticAssertDecl(BLCKSZ == ((BLCKSZ / sizeof(size_t)) * sizeof(size_t)),
 				 "BLCKSZ has to be a multiple of sizeof(size_t)");
 
+/*
+ * Tuple defrag support for PageRepairFragmentation and PageIndexMultiDelete
+ */
+typedef struct ItemIdCompactData
+{
+	uint16		offsetindex;	/* linp array index */
+	int16		itemoff;		/* page offset of item data */
+	uint16		alignedlen;		/* MAXALIGN(item data len) */
+} ItemIdCompactData;
+
+typedef ItemIdCompactData *ItemIdCompact;
+typedef RelationData *Relation;
+
+extern int	itemoffcompare(const void *item1, const void *item2);
+
 extern void PageInit(Page page, Size pageSize, Size specialSize);
 extern bool PageIsVerifiedExtended(Page page, BlockNumber blkno, int flags);
 extern OffsetNumber PageAddItemExtended(Page page, Item item, Size size,
@@ -440,7 +649,7 @@ extern Page PageGetTempPage(Page page);
 extern Page PageGetTempPageCopy(Page page);
 extern Page PageGetTempPageCopySpecial(Page page);
 extern void PageRestoreTempPage(Page tempPage, Page oldPage);
-extern void PageRepairFragmentation(Page page);
+extern void PageRepairFragmentation(Page page, bool is_toast);
 extern void PageTruncateLinePointerArray(Page page);
 extern Size PageGetFreeSpace(Page page);
 extern Size PageGetFreeSpaceForMultipleTuples(Page page, int ntups);
diff --git a/src/include/storage/itemid.h b/src/include/storage/itemid.h
index e33637ff21..442a72d658 100644
--- a/src/include/storage/itemid.h
+++ b/src/include/storage/itemid.h
@@ -78,6 +78,8 @@ typedef uint16 ItemLength;
 #define ItemIdGetRedirect(itemId) \
    ((itemId)->lp_off)
 
+#define ItemIdGetTupleEnd(itemId) \
+	(MAXALIGN(ItemIdGetLength((itemId))) + ItemIdGetOffset((itemId)))
 /*
  * ItemIdIsValid
  *		True iff item identifier is valid.
diff --git a/src/include/storage/lock.h b/src/include/storage/lock.h
index e4e1495b24..0e0cd79bb0 100644
--- a/src/include/storage/lock.h
+++ b/src/include/storage/lock.h
@@ -227,8 +227,8 @@ typedef struct LOCKTAG
 
 /* ID info for a transaction is its TransactionId */
 #define SET_LOCKTAG_TRANSACTION(locktag,xid) \
-	((locktag).locktag_field1 = (xid), \
-	 (locktag).locktag_field2 = 0, \
+	((locktag).locktag_field1 = (uint32)((xid) & 0xFFFFFFFF), \
+	 (locktag).locktag_field2 = (uint32)((xid) >> 32), \
 	 (locktag).locktag_field3 = 0, \
 	 (locktag).locktag_field4 = 0, \
 	 (locktag).locktag_type = LOCKTAG_TRANSACTION, \
@@ -237,8 +237,8 @@ typedef struct LOCKTAG
 /* ID info for a virtual transaction is its VirtualTransactionId */
 #define SET_LOCKTAG_VIRTUALTRANSACTION(locktag,vxid) \
 	((locktag).locktag_field1 = (vxid).backendId, \
-	 (locktag).locktag_field2 = (vxid).localTransactionId, \
-	 (locktag).locktag_field3 = 0, \
+	 (locktag).locktag_field2 = (uint32)((vxid).localTransactionId & 0xFFFFFFFF), \
+	 (locktag).locktag_field3 = (uint32)((vxid).localTransactionId >> 32), \
 	 (locktag).locktag_field4 = 0, \
 	 (locktag).locktag_type = LOCKTAG_VIRTUALTRANSACTION, \
 	 (locktag).locktag_lockmethodid = DEFAULT_LOCKMETHOD)
@@ -248,9 +248,9 @@ typedef struct LOCKTAG
  * its speculative insert counter.
  */
 #define SET_LOCKTAG_SPECULATIVE_INSERTION(locktag,xid,token) \
-	((locktag).locktag_field1 = (xid), \
-	 (locktag).locktag_field2 = (token),		\
-	 (locktag).locktag_field3 = 0, \
+	((locktag).locktag_field1 = (uint32)((xid) & 0xFFFFFFFF), \
+	 (locktag).locktag_field2 = (uint32)((xid) >> 32), \
+	 (locktag).locktag_field3 = (token),		\
 	 (locktag).locktag_field4 = 0, \
 	 (locktag).locktag_type = LOCKTAG_SPECULATIVE_TOKEN, \
 	 (locktag).locktag_lockmethodid = DEFAULT_LOCKMETHOD)
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h
index 1f028233c7..b2e5958d51 100644
--- a/src/include/storage/proc.h
+++ b/src/include/storage/proc.h
@@ -17,6 +17,7 @@
 #include "access/clog.h"
 #include "access/xlogdefs.h"
 #include "lib/ilist.h"
+#include "port/atomics.h"
 #include "storage/latch.h"
 #include "storage/lock.h"
 #include "storage/pg_sema.h"
@@ -174,12 +175,12 @@ struct PGPROC
 	Latch		procLatch;		/* generic latch for process */
 
 
-	TransactionId xid;			/* id of top-level transaction currently being
+	pg_atomic_uint64 xid;		/* id of top-level transaction currently being
 								 * executed by this proc, if running and XID
 								 * is assigned; else InvalidTransactionId.
 								 * mirrored in ProcGlobal->xids[pgxactoff] */
 
-	TransactionId xmin;			/* minimal running XID as it was when we were
+	pg_atomic_uint64 xmin;			/* minimal running XID as it was when we were
 								 * starting our xact, excluding LAZY VACUUM:
 								 * vacuum must not remove tuples deleted by
 								 * xid >= xmin ! */
@@ -362,7 +363,7 @@ typedef struct PROC_HDR
 	PGPROC	   *allProcs;
 
 	/* Array mirroring PGPROC.xid for each PGPROC currently in the procarray */
-	TransactionId *xids;
+	pg_atomic_uint64 *xids;
 
 	/*
 	 * Array mirroring PGPROC.subxidStatus for each PGPROC currently in the
diff --git a/src/include/storage/standby.h b/src/include/storage/standby.h
index dacef92f44..1b8dbdd043 100644
--- a/src/include/storage/standby.h
+++ b/src/include/storage/standby.h
@@ -21,7 +21,7 @@
 #include "storage/standbydefs.h"
 
 /* User-settable GUC parameters */
-extern PGDLLIMPORT int vacuum_defer_cleanup_age;
+extern PGDLLIMPORT int64 vacuum_defer_cleanup_age;
 extern PGDLLIMPORT int max_standby_archive_delay;
 extern PGDLLIMPORT int max_standby_streaming_delay;
 extern PGDLLIMPORT bool log_recovery_conflict_waits;
diff --git a/src/include/utils/combocid.h b/src/include/utils/combocid.h
index 80fe6d2cea..8465768b6f 100644
--- a/src/include/utils/combocid.h
+++ b/src/include/utils/combocid.h
@@ -15,7 +15,7 @@
 #define COMBOCID_H
 
 /*
- * HeapTupleHeaderGetCmin and HeapTupleHeaderGetCmax function prototypes
+ * HeapTupleGetCmin and HeapTupleGetCmax function prototypes
  * are in access/htup.h, because that's where the macro definitions that
  * those functions replaced used to be.
  */
diff --git a/src/include/utils/rel.h b/src/include/utils/rel.h
index b741105d1e..200cbcadb4 100644
--- a/src/include/utils/rel.h
+++ b/src/include/utils/rel.h
@@ -306,12 +306,12 @@ typedef struct AutoVacOpts
 	int			vacuum_ins_threshold;
 	int			analyze_threshold;
 	int			vacuum_cost_limit;
-	int			freeze_min_age;
-	int			freeze_max_age;
-	int			freeze_table_age;
-	int			multixact_freeze_min_age;
-	int			multixact_freeze_max_age;
-	int			multixact_freeze_table_age;
+	int64		freeze_min_age;
+	int64		freeze_max_age;
+	int64		freeze_table_age;
+	int64		multixact_freeze_min_age;
+	int64		multixact_freeze_max_age;
+	int64		multixact_freeze_table_age;
 	int			log_min_duration;
 	float8		vacuum_cost_delay;
 	float8		vacuum_scale_factor;
diff --git a/src/include/utils/xid8.h b/src/include/utils/xid8.h
index b702fc1a91..284df5027b 100644
--- a/src/include/utils/xid8.h
+++ b/src/include/utils/xid8.h
@@ -14,8 +14,8 @@
 
 #include "access/transam.h"
 
-#define DatumGetFullTransactionId(X) (FullTransactionIdFromU64(DatumGetUInt64(X)))
-#define FullTransactionIdGetDatum(X) (UInt64GetDatum(U64FromFullTransactionId(X)))
+#define DatumGetFullTransactionId(X) (FullTransactionIdFromXid(DatumGetUInt64(X)))
+#define FullTransactionIdGetDatum(X) (UInt64GetDatum(XidFromFullTransactionId(X)))
 #define PG_GETARG_FULLTRANSACTIONID(X) DatumGetFullTransactionId(PG_GETARG_DATUM(X))
 #define PG_RETURN_FULLTRANSACTIONID(X) return FullTransactionIdGetDatum(X)
 
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index edb93ec1c4..b29ef18645 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -2667,7 +2667,7 @@ validate_plperl_function(plperl_proc_ptr *proc_ptr, HeapTuple procTup)
 		 * This is needed because CREATE OR REPLACE FUNCTION can modify the
 		 * function's pg_proc entry without changing its OID.
 		 ************************************************************/
-		uptodate = (prodesc->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
+		uptodate = (prodesc->fn_xmin == HeapTupleGetRawXmin(procTup) &&
 					ItemPointerEquals(&prodesc->fn_tid, &procTup->t_self));
 
 		if (uptodate)
@@ -2791,7 +2791,7 @@ compile_plperl_function(Oid fn_oid, bool is_trigger, bool is_event_trigger)
 		MemoryContextSetIdentifier(proc_cxt, prodesc->proname);
 		prodesc->fn_cxt = proc_cxt;
 		prodesc->fn_refcount = 0;
-		prodesc->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
+		prodesc->fn_xmin = HeapTupleGetRawXmin(procTup);
 		prodesc->fn_tid = procTup->t_self;
 		prodesc->nargs = procStruct->pronargs;
 		prodesc->arg_out_func = (FmgrInfo *) palloc0(prodesc->nargs * sizeof(FmgrInfo));
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index b791c23f06..820db4c0e4 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -171,7 +171,7 @@ recheck:
 	if (function)
 	{
 		/* We have a compiled function, but is it still valid? */
-		if (function->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
+		if (function->fn_xmin == HeapTupleGetRawXmin(procTup) &&
 			ItemPointerEquals(&function->fn_tid, &procTup->t_self))
 			function_valid = true;
 		else
@@ -348,7 +348,7 @@ do_compile(FunctionCallInfo fcinfo,
 	function->fn_signature = format_procedure(fcinfo->flinfo->fn_oid);
 	MemoryContextSetIdentifier(func_cxt, function->fn_signature);
 	function->fn_oid = fcinfo->flinfo->fn_oid;
-	function->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
+	function->fn_xmin = HeapTupleGetRawXmin(procTup);
 	function->fn_tid = procTup->t_self;
 	function->fn_input_collation = fcinfo->fncollation;
 	function->fn_cxt = func_cxt;
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 7bd2a9fff1..9cde92cd91 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -7376,6 +7376,7 @@ deconstruct_composite_datum(Datum value, HeapTupleData *tmptup)
 	tmptup->t_len = HeapTupleHeaderGetDatumLength(td);
 	ItemPointerSetInvalid(&(tmptup->t_self));
 	tmptup->t_tableOid = InvalidOid;
+	HeapTupleSetZeroBase(tmptup);
 	tmptup->t_data = td;
 
 	/* Extract rowtype info and find a tupdesc */
@@ -7550,6 +7551,7 @@ exec_move_row_from_datum(PLpgSQL_execstate *estate,
 		tmptup.t_len = HeapTupleHeaderGetDatumLength(td);
 		ItemPointerSetInvalid(&(tmptup.t_self));
 		tmptup.t_tableOid = InvalidOid;
+		HeapTupleSetZeroBase(&tmptup);
 		tmptup.t_data = td;
 
 		/* Extract rowtype info */
diff --git a/src/pl/plpython/plpy_procedure.c b/src/pl/plpython/plpy_procedure.c
index 494f109b32..9884f74fa7 100644
--- a/src/pl/plpython/plpy_procedure.c
+++ b/src/pl/plpython/plpy_procedure.c
@@ -178,7 +178,7 @@ PLy_procedure_create(HeapTuple procTup, Oid fn_oid, bool is_trigger)
 		proc->proname = pstrdup(NameStr(procStruct->proname));
 		MemoryContextSetIdentifier(cxt, proc->proname);
 		proc->pyname = pstrdup(procName);
-		proc->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
+		proc->fn_xmin = HeapTupleGetRawXmin(procTup);
 		proc->fn_tid = procTup->t_self;
 		proc->fn_readonly = (procStruct->provolatile != PROVOLATILE_VOLATILE);
 		proc->is_setof = procStruct->proretset;
@@ -419,7 +419,7 @@ PLy_procedure_valid(PLyProcedure *proc, HeapTuple procTup)
 		return false;
 
 	/* If the pg_proc tuple has changed, it's not valid */
-	if (!(proc->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
+	if (!(proc->fn_xmin == HeapTupleGetRawXmin(procTup) &&
 		  ItemPointerEquals(&proc->fn_tid, &procTup->t_self)))
 		return false;
 
diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
index 0dd6d8ab2c..ac2354a0cb 100644
--- a/src/pl/tcl/pltcl.c
+++ b/src/pl/tcl/pltcl.c
@@ -1429,7 +1429,7 @@ compile_pltcl_function(Oid fn_oid, Oid tgreloid,
 	 * function's pg_proc entry without changing its OID.
 	 ************************************************************/
 	if (prodesc != NULL &&
-		prodesc->fn_xmin == HeapTupleHeaderGetRawXmin(procTup->t_data) &&
+		prodesc->fn_xmin == HeapTupleGetRawXmin(procTup) &&
 		ItemPointerEquals(&prodesc->fn_tid, &procTup->t_self))
 	{
 		/* It's still up-to-date, so we can use it */
@@ -1496,7 +1496,7 @@ compile_pltcl_function(Oid fn_oid, Oid tgreloid,
 		prodesc->internal_proname = pstrdup(internal_proname);
 		prodesc->fn_cxt = proc_cxt;
 		prodesc->fn_refcount = 0;
-		prodesc->fn_xmin = HeapTupleHeaderGetRawXmin(procTup->t_data);
+		prodesc->fn_xmin = HeapTupleGetRawXmin(procTup);
 		prodesc->fn_tid = procTup->t_self;
 		prodesc->nargs = procStruct->pronargs;
 		prodesc->arg_out_func = (FmgrInfo *) palloc0(prodesc->nargs * sizeof(FmgrInfo));
diff --git a/src/test/Makefile b/src/test/Makefile
index 69ef074d75..53ddfffb94 100644
--- a/src/test/Makefile
+++ b/src/test/Makefile
@@ -12,7 +12,8 @@ subdir = src/test
 top_builddir = ../..
 include $(top_builddir)/src/Makefile.global
 
-SUBDIRS = perl regress isolation modules authentication recovery subscription
+SUBDIRS = perl regress isolation modules authentication recovery subscription \
+		xid-64
 
 ifeq ($(with_icu),yes)
 SUBDIRS += icu
diff --git a/src/test/perl/PostgreSQL/Test/Cluster.pm b/src/test/perl/PostgreSQL/Test/Cluster.pm
index c8c7bc5045..2da5c8dc02 100644
--- a/src/test/perl/PostgreSQL/Test/Cluster.pm
+++ b/src/test/perl/PostgreSQL/Test/Cluster.pm
@@ -476,7 +476,9 @@ sub init
 	mkdir $self->archive_dir;
 
 	PostgreSQL::Test::Utils::system_or_bail('initdb', '-D', $pgdata, '-A',
-		'trust', '-N', @{ $params{extra} });
+		'trust', '-N',
+		'-x', '1249835483136', '-m', '2422361554944', '-o', '3594887626752',
+		@{ $params{extra} });
 	PostgreSQL::Test::Utils::system_or_bail($ENV{PG_REGRESS},
 		'--config-auth', $pgdata, @{ $params{auth_extra} });
 
diff --git a/src/test/recovery/t/003_recovery_targets.pl b/src/test/recovery/t/003_recovery_targets.pl
index e8e1a420bc..8329d2ff7e 100644
--- a/src/test/recovery/t/003_recovery_targets.pl
+++ b/src/test/recovery/t/003_recovery_targets.pl
@@ -57,7 +57,7 @@ $node_primary->init(has_archiving => 1, allows_streaming => 1);
 
 # Bump the transaction ID epoch.  This is useful to stress the portability
 # of recovery_target_xid parsing.
-system_or_bail('pg_resetwal', '--epoch', '1', $node_primary->data_dir);
+system_or_bail('pg_resetwal',  $node_primary->data_dir);
 
 # Start it
 $node_primary->start;
diff --git a/src/test/regress/expected/indirect_toast.out b/src/test/regress/expected/indirect_toast.out
index 44b54dc37f..313482b866 100644
--- a/src/test/regress/expected/indirect_toast.out
+++ b/src/test/regress/expected/indirect_toast.out
@@ -161,6 +161,14 @@ SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
  ("one-toasted,one-null, via indirect",0,1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890
 (5 rows)
 
+create or replace function random_string(len integer) returns text as $$
+select substr((select string_agg(r,'') from (select random()::text as r from generate_series(1,(len+15)/16)) s1), 1, len);
+$$ language sql;
+create table toasttest_main(t text);
+alter table toasttest_main alter column t set storage main;
+insert into toasttest_main (select random_string(len) from generate_series(7000,8000) len);
 DROP TABLE indtoasttest;
+DROP TABLE toasttest_main;
 DROP FUNCTION update_using_indirect();
+DROP FUNCTION random_string(integer);
 RESET default_toast_compression;
diff --git a/src/test/regress/expected/insert.out b/src/test/regress/expected/insert.out
index dd4354fc7d..d52545b443 100644
--- a/src/test/regress/expected/insert.out
+++ b/src/test/regress/expected/insert.out
@@ -100,7 +100,7 @@ SELECT pg_size_pretty(pg_relation_size('large_tuple_test'::regclass, 'main'));
 INSERT INTO large_tuple_test (select 3, NULL);
 -- now this tuple won't fit on the second page, but the insert should
 -- still succeed by extending the relation
-INSERT INTO large_tuple_test (select 4, repeat('a', 8126));
+INSERT INTO large_tuple_test (select 4, repeat('a', 8112));
 DROP TABLE large_tuple_test;
 --
 -- check indirection (field/array assignment), cf bug #14265
@@ -980,3 +980,17 @@ insert into returningwrtest values (2, 'foo') returning returningwrtest;
 (1 row)
 
 drop table returningwrtest;
+-- Check for MaxHeapTupleSize
+create table maxheaptuplesize_test(value text);
+alter table maxheaptuplesize_test alter column value set storage external;
+insert into maxheaptuplesize_test values (repeat('x', 8104));
+insert into maxheaptuplesize_test values (repeat('x', 8112));
+insert into maxheaptuplesize_test values (repeat('x', 8120));
+insert into maxheaptuplesize_test values (repeat('x', 8128));
+insert into maxheaptuplesize_test values (repeat('x', 8136));
+insert into maxheaptuplesize_test values (repeat('x', 8144));
+insert into maxheaptuplesize_test values (repeat('x', 8152));
+insert into maxheaptuplesize_test values (repeat('x', 8160));
+insert into maxheaptuplesize_test values (repeat('x', 8168));
+insert into maxheaptuplesize_test values (repeat('x', 8176));
+drop table maxheaptuplesize_test;
diff --git a/src/test/regress/expected/opr_sanity.out b/src/test/regress/expected/opr_sanity.out
index 86d755aa44..317d0f1b8b 100644
--- a/src/test/regress/expected/opr_sanity.out
+++ b/src/test/regress/expected/opr_sanity.out
@@ -197,7 +197,7 @@ WHERE p1.oid != p2.oid AND
 ORDER BY 1, 2;
          proargtypes         |       proargtypes        
 -----------------------------+--------------------------
- integer                     | xid
+ bigint                      | xid
  timestamp without time zone | timestamp with time zone
  bit                         | bit varying
  txid_snapshot               | pg_snapshot
@@ -705,7 +705,7 @@ int8(oid)
 tideq(tid,tid)
 timestamptz_cmp(timestamp with time zone,timestamp with time zone)
 interval_cmp(interval,interval)
-xideqint4(xid,integer)
+xideqint8(xid,bigint)
 timetz_eq(time with time zone,time with time zone)
 timetz_ne(time with time zone,time with time zone)
 timetz_lt(time with time zone,time with time zone)
@@ -819,7 +819,7 @@ pg_lsn_gt(pg_lsn,pg_lsn)
 pg_lsn_ne(pg_lsn,pg_lsn)
 pg_lsn_cmp(pg_lsn,pg_lsn)
 xidneq(xid,xid)
-xidneqint4(xid,integer)
+xidneqint8(xid,bigint)
 sha224(bytea)
 sha256(bytea)
 sha384(bytea)
diff --git a/src/test/regress/expected/select_views.out b/src/test/regress/expected/select_views.out
index 1aeed8452b..d3be84754c 100644
--- a/src/test/regress/expected/select_views.out
+++ b/src/test/regress/expected/select_views.out
@@ -2,9 +2,22 @@
 -- SELECT_VIEWS
 -- test the views defined in CREATE_VIEWS
 --
-SELECT * FROM street;
+SELECT * FROM street ORDER BY name COLLATE "C", thepath::text COLLATE "C";
                 name                |                                                                                                                                                                                                                   thepath                                                                                                                                                                                                                    |   cname   
 ------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-----------
+ 100th                         Ave  | [(-122.1657,37.429),(-122.1647,37.432)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
+ 107th                         Ave  | [(-122.1555,37.403),(-122.1531,37.41)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
+ 14th                          St   | [(-122.299,37.147),(-122.3,37.148)]                                                                                                                                                                                                                                                                                                                                                                                                          | Lafayette
+ 19th                          Ave  | [(-122.2366,37.897),(-122.2359,37.905)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
+ 1st                           St   | [(-121.75508,37.89294),(-121.753581,37.90031)]                                                                                                                                                                                                                                                                                                                                                                                               | Oakland
+ 5th                           St   | [(-122.278,37),(-122.2792,37.005),(-122.2803,37.009)]                                                                                                                                                                                                                                                                                                                                                                                        | Lafayette
+ 5th                           St   | [(-122.296,37.615),(-122.2953,37.598)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
+ 82nd                          Ave  | [(-122.1695,37.596),(-122.1681,37.603)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
+ 85th                          Ave  | [(-122.1877,37.466),(-122.186,37.476)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
+ 89th                          Ave  | [(-122.1822,37.459),(-122.1803,37.471)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
+ 98th                          Ave  | [(-122.1568,37.498),(-122.1558,37.502)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
+ 98th                          Ave  | [(-122.1693,37.438),(-122.1682,37.444)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
+ 98th                          Ave  | [(-122.2001,37.258),(-122.1974,37.27)]                                                                                                                                                                                                                                                                                                                                                                                                       | Lafayette
  Access Rd 25                       | [(-121.9283,37.894),(-121.9283,37.9)]                                                                                                                                                                                                                                                                                                                                                                                                        | Oakland
  Ada                           St   | [(-122.2487,37.398),(-122.2496,37.401)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
  Agua Fria Creek                    | [(-121.9254,37.922),(-121.9281,37.889)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
@@ -22,8 +35,8 @@ SELECT * FROM street;
  Arroyo Las Positas                 | [(-121.7973,37.997),(-121.7957,37.005)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Arroyo Seco                        | [(-121.7073,37.766),(-121.6997,37.729)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Ash                           St   | [(-122.0408,37.31),(-122.04,37.292)]                                                                                                                                                                                                                                                                                                                                                                                                         | Oakland
- Avenue 134th                       | [(-122.1823,37.002),(-122.1851,37.992)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Avenue 134th                       | [(-122.1823,37.002),(-122.1851,37.992)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
+ Avenue 134th                       | [(-122.1823,37.002),(-122.1851,37.992)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Avenue 140th                       | [(-122.1656,37.003),(-122.1691,37.988)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Avenue 140th                       | [(-122.1656,37.003),(-122.1691,37.988)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Avenue D                           | [(-122.298,37.848),(-122.3024,37.849)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
@@ -37,14 +50,14 @@ SELECT * FROM street;
  Broadmore                     Ave  | [(-122.095,37.522),(-122.0936,37.497)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Broadway                           | [(-122.2409,37.586),(-122.2395,37.601)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Buckingham                    Blvd | [(-122.2231,37.59),(-122.2214,37.606)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
+ Butterfield                   Dr   | [(-122.0838,37.002),(-122.0834,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Butterfield                   Dr   | [(-122.0838,37.002),(-122.0834,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Butterfield                   Dr   | [(-122.0838,37.002),(-122.0834,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- Butterfield                   Dr   | [(-122.0838,37.002),(-122.0834,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  C                             St   | [(-122.1768,37.46),(-122.1749,37.435)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Calaveras Creek                    | [(-121.8203,37.035),(-121.8207,37.931)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Calaveras Creek                    | [(-121.8203,37.035),(-121.8207,37.931)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- California                    St   | [(-122.2032,37.005),(-122.2016,37.996)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  California                    St   | [(-122.2032,37.005),(-122.2016,37.996)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
+ California                    St   | [(-122.2032,37.005),(-122.2016,37.996)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Cameron                       Ave  | [(-122.1316,37.502),(-122.1327,37.481)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Campus                        Dr   | [(-122.1704,37.905),(-122.1678,37.868),(-122.1671,37.865)]                                                                                                                                                                                                                                                                                                                                                                                   | Berkeley
  Capricorn                     Ave  | [(-122.2176,37.404),(-122.2164,37.384)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
@@ -55,8 +68,8 @@ SELECT * FROM street;
  Central                       Ave  | [(-122.2343,37.602),(-122.2331,37.595)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Chambers                      Dr   | [(-122.2004,37.352),(-122.1972,37.368)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
  Chambers                      Lane | [(-122.2001,37.359),(-122.1975,37.371)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
- Champion                      St   | [(-122.214,37.991),(-122.2147,37.002)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
  Champion                      St   | [(-122.214,37.991),(-122.2147,37.002)]                                                                                                                                                                                                                                                                                                                                                                                                       | Lafayette
+ Champion                      St   | [(-122.214,37.991),(-122.2147,37.002)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
  Chapman                       Dr   | [(-122.0421,37.504),(-122.0414,37.498)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Charles                       St   | [(-122.0255,37.505),(-122.0252,37.499)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Cherry                        St   | [(-122.0437,37.42),(-122.0434,37.413)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
@@ -77,9 +90,9 @@ SELECT * FROM street;
  Cull Canyon                   Road | [(-122.0536,37.435),(-122.0499,37.315)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Cull Creek                         | [(-122.0624,37.875),(-122.0582,37.527)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  D                             St   | [(-122.1811,37.505),(-122.1805,37.497)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
+ Decoto                        Road | [(-122.0159,37.006),(-122.016,37.002),(-122.0164,37.993)]                                                                                                                                                                                                                                                                                                                                                                                    | Berkeley
  Decoto                        Road | [(-122.0159,37.006),(-122.016,37.002),(-122.0164,37.993)]                                                                                                                                                                                                                                                                                                                                                                                    | Oakland
  Decoto                        Road | [(-122.0159,37.006),(-122.016,37.002),(-122.0164,37.993)]                                                                                                                                                                                                                                                                                                                                                                                    | Oakland
- Decoto                        Road | [(-122.0159,37.006),(-122.016,37.002),(-122.0164,37.993)]                                                                                                                                                                                                                                                                                                                                                                                    | Berkeley
  Deering                       St   | [(-122.2146,37.904),(-122.2126,37.897)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Dimond                        Ave  | [(-122.2167,37.994),(-122.2162,37.006)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Dimond                        Ave  | [(-122.2167,37.994),(-122.2162,37.006)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
@@ -117,12 +130,12 @@ SELECT * FROM street;
  I- 580                             | [(-121.9322,37.989),(-121.9243,37.006),(-121.9217,37.014)]                                                                                                                                                                                                                                                                                                                                                                                   | Oakland
  I- 580                             | [(-122.018,37.019),(-122.0009,37.032),(-121.9787,37.983),(-121.958,37.984),(-121.9571,37.986)]                                                                                                                                                                                                                                                                                                                                               | Oakland
  I- 580                             | [(-122.018,37.019),(-122.0009,37.032),(-121.9787,37.983),(-121.958,37.984),(-121.9571,37.986)]                                                                                                                                                                                                                                                                                                                                               | Oakland
- I- 580                             | [(-122.1108,37.023),(-122.1101,37.02),(-122.108103,37.00764),(-122.108,37.007),(-122.1069,37.998),(-122.1064,37.994),(-122.1053,37.982),(-122.1048,37.977),(-122.1032,37.958),(-122.1026,37.953),(-122.1013,37.938),(-122.0989,37.911),(-122.0984,37.91),(-122.098,37.908)]                                                                                                                                                                  | Oakland
  I- 580                             | [(-122.1108,37.023),(-122.1101,37.02),(-122.108103,37.00764),(-122.108,37.007),(-122.1069,37.998),(-122.1064,37.994),(-122.1053,37.982),(-122.1048,37.977),(-122.1032,37.958),(-122.1026,37.953),(-122.1013,37.938),(-122.0989,37.911),(-122.0984,37.91),(-122.098,37.908)]                                                                                                                                                                  | Berkeley
+ I- 580                             | [(-122.1108,37.023),(-122.1101,37.02),(-122.108103,37.00764),(-122.108,37.007),(-122.1069,37.998),(-122.1064,37.994),(-122.1053,37.982),(-122.1048,37.977),(-122.1032,37.958),(-122.1026,37.953),(-122.1013,37.938),(-122.0989,37.911),(-122.0984,37.91),(-122.098,37.908)]                                                                                                                                                                  | Oakland
  I- 580                             | [(-122.1543,37.703),(-122.1535,37.694),(-122.1512,37.655),(-122.1475,37.603),(-122.1468,37.583),(-122.1472,37.569),(-122.149044,37.54874),(-122.1493,37.546),(-122.1501,37.532),(-122.1506,37.509),(-122.1495,37.482),(-122.1487,37.467),(-122.1477,37.447),(-122.1414,37.383),(-122.1404,37.376),(-122.1398,37.372),(-122.139,37.356),(-122.1388,37.353),(-122.1385,37.34),(-122.1382,37.33),(-122.1378,37.316)]                            | Oakland
  I- 580                             | [(-122.1543,37.703),(-122.1535,37.694),(-122.1512,37.655),(-122.1475,37.603),(-122.1468,37.583),(-122.1472,37.569),(-122.149044,37.54874),(-122.1493,37.546),(-122.1501,37.532),(-122.1506,37.509),(-122.1495,37.482),(-122.1487,37.467),(-122.1477,37.447),(-122.1414,37.383),(-122.1404,37.376),(-122.1398,37.372),(-122.139,37.356),(-122.1388,37.353),(-122.1385,37.34),(-122.1382,37.33),(-122.1378,37.316)]                            | Berkeley
- I- 580                             | [(-122.2197,37.99),(-122.22,37.99),(-122.222092,37.99523),(-122.2232,37.998),(-122.224146,37.99963),(-122.2261,37.003),(-122.2278,37.007),(-122.2302,37.026),(-122.2323,37.043),(-122.2344,37.059),(-122.235405,37.06427),(-122.2365,37.07)]                                                                                                                                                                                                 | Berkeley
  I- 580                             | [(-122.2197,37.99),(-122.22,37.99),(-122.222092,37.99523),(-122.2232,37.998),(-122.224146,37.99963),(-122.2261,37.003),(-122.2278,37.007),(-122.2302,37.026),(-122.2323,37.043),(-122.2344,37.059),(-122.235405,37.06427),(-122.2365,37.07)]                                                                                                                                                                                                 | Lafayette
+ I- 580                             | [(-122.2197,37.99),(-122.22,37.99),(-122.222092,37.99523),(-122.2232,37.998),(-122.224146,37.99963),(-122.2261,37.003),(-122.2278,37.007),(-122.2302,37.026),(-122.2323,37.043),(-122.2344,37.059),(-122.235405,37.06427),(-122.2365,37.07)]                                                                                                                                                                                                 | Berkeley
  I- 580                        Ramp | [(-121.8521,37.011),(-121.8479,37.999),(-121.8476,37.999),(-121.8456,37.01),(-121.8455,37.011)]                                                                                                                                                                                                                                                                                                                                              | Oakland
  I- 580                        Ramp | [(-121.8521,37.011),(-121.8479,37.999),(-121.8476,37.999),(-121.8456,37.01),(-121.8455,37.011)]                                                                                                                                                                                                                                                                                                                                              | Oakland
  I- 580                        Ramp | [(-121.8743,37.014),(-121.8722,37.999),(-121.8714,37.999)]                                                                                                                                                                                                                                                                                                                                                                                   | Oakland
@@ -136,8 +149,8 @@ SELECT * FROM street;
  I- 580                        Ramp | [(-122.0941,37.897),(-122.0943,37.902)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  I- 580                        Ramp | [(-122.096,37.888),(-122.0962,37.891),(-122.0964,37.9)]                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  I- 580                        Ramp | [(-122.101,37.898),(-122.1005,37.902),(-122.0989,37.911)]                                                                                                                                                                                                                                                                                                                                                                                    | Berkeley
- I- 580                        Ramp | [(-122.1086,37.003),(-122.1068,37.993),(-122.1066,37.992),(-122.1053,37.982)]                                                                                                                                                                                                                                                                                                                                                                | Oakland
  I- 580                        Ramp | [(-122.1086,37.003),(-122.1068,37.993),(-122.1066,37.992),(-122.1053,37.982)]                                                                                                                                                                                                                                                                                                                                                                | Berkeley
+ I- 580                        Ramp | [(-122.1086,37.003),(-122.1068,37.993),(-122.1066,37.992),(-122.1053,37.982)]                                                                                                                                                                                                                                                                                                                                                                | Oakland
  I- 580                        Ramp | [(-122.1414,37.383),(-122.1407,37.376),(-122.1403,37.372),(-122.139,37.356)]                                                                                                                                                                                                                                                                                                                                                                 | Oakland
  I- 580/I-680                  Ramp | ((-121.9207,37.988),(-121.9192,37.016))                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  I- 580/I-680                  Ramp | ((-121.9207,37.988),(-121.9192,37.016))                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
@@ -158,16 +171,16 @@ SELECT * FROM street;
  I- 880                             | ((-121.9669,37.075),(-121.9663,37.071),(-121.9656,37.065),(-121.9618,37.037),(-121.95689,37),(-121.948,37.933))                                                                                                                                                                                                                                                                                                                              | Oakland
  I- 880                             | [(-121.948,37.933),(-121.9471,37.925),(-121.9467,37.923),(-121.946,37.918),(-121.9452,37.912),(-121.937,37.852)]                                                                                                                                                                                                                                                                                                                             | Oakland
  I- 880                             | [(-122.0219,37.466),(-122.0205,37.447),(-122.020331,37.44447),(-122.020008,37.43962),(-122.0195,37.432),(-122.0193,37.429),(-122.0164,37.393),(-122.010219,37.34771),(-122.0041,37.313)]                                                                                                                                                                                                                                                     | Oakland
- I- 880                             | [(-122.0375,37.632),(-122.0359,37.619),(-122.0358,37.616),(-122.034514,37.60409),(-122.031876,37.57965),(-122.031193,37.57332),(-122.03016,37.56375),(-122.02943,37.55698),(-122.028689,37.54929),(-122.027833,37.53908),(-122.025979,37.51698),(-122.0238,37.491)]                                                                                                                                                                          | Oakland
  I- 880                             | [(-122.0375,37.632),(-122.0359,37.619),(-122.0358,37.616),(-122.034514,37.60409),(-122.031876,37.57965),(-122.031193,37.57332),(-122.03016,37.56375),(-122.02943,37.55698),(-122.028689,37.54929),(-122.027833,37.53908),(-122.025979,37.51698),(-122.0238,37.491)]                                                                                                                                                                          | Berkeley
- I- 880                             | [(-122.0612,37.003),(-122.0604,37.991),(-122.0596,37.982),(-122.0585,37.967),(-122.0583,37.961),(-122.0553,37.918),(-122.053635,37.89475),(-122.050759,37.8546),(-122.05,37.844),(-122.0485,37.817),(-122.0483,37.813),(-122.0482,37.811)]                                                                                                                                                                                                   | Oakland
+ I- 880                             | [(-122.0375,37.632),(-122.0359,37.619),(-122.0358,37.616),(-122.034514,37.60409),(-122.031876,37.57965),(-122.031193,37.57332),(-122.03016,37.56375),(-122.02943,37.55698),(-122.028689,37.54929),(-122.027833,37.53908),(-122.025979,37.51698),(-122.0238,37.491)]                                                                                                                                                                          | Oakland
  I- 880                             | [(-122.0612,37.003),(-122.0604,37.991),(-122.0596,37.982),(-122.0585,37.967),(-122.0583,37.961),(-122.0553,37.918),(-122.053635,37.89475),(-122.050759,37.8546),(-122.05,37.844),(-122.0485,37.817),(-122.0483,37.813),(-122.0482,37.811)]                                                                                                                                                                                                   | Oakland
  I- 880                             | [(-122.0612,37.003),(-122.0604,37.991),(-122.0596,37.982),(-122.0585,37.967),(-122.0583,37.961),(-122.0553,37.918),(-122.053635,37.89475),(-122.050759,37.8546),(-122.05,37.844),(-122.0485,37.817),(-122.0483,37.813),(-122.0482,37.811)]                                                                                                                                                                                                   | Berkeley
+ I- 880                             | [(-122.0612,37.003),(-122.0604,37.991),(-122.0596,37.982),(-122.0585,37.967),(-122.0583,37.961),(-122.0553,37.918),(-122.053635,37.89475),(-122.050759,37.8546),(-122.05,37.844),(-122.0485,37.817),(-122.0483,37.813),(-122.0482,37.811)]                                                                                                                                                                                                   | Oakland
  I- 880                             | [(-122.0831,37.312),(-122.0819,37.296),(-122.081,37.285),(-122.0786,37.248),(-122.078,37.24),(-122.077642,37.23496),(-122.076983,37.22567),(-122.076599,37.22026),(-122.076229,37.21505),(-122.0758,37.209)]                                                                                                                                                                                                                                 | Oakland
  I- 880                             | [(-122.0978,37.528),(-122.096,37.496),(-122.0931,37.453),(-122.09277,37.4496),(-122.090189,37.41442),(-122.0896,37.405),(-122.085,37.34)]                                                                                                                                                                                                                                                                                                    | Oakland
  I- 880                             | [(-122.1365,37.902),(-122.1358,37.898),(-122.1333,37.881),(-122.1323,37.874),(-122.1311,37.866),(-122.1308,37.865),(-122.1307,37.864),(-122.1289,37.851),(-122.1277,37.843),(-122.1264,37.834),(-122.1231,37.812),(-122.1165,37.766),(-122.1104,37.72),(-122.109695,37.71094),(-122.109,37.702),(-122.108312,37.69168),(-122.1076,37.681)]                                                                                                   | Berkeley
- I- 880                             | [(-122.1755,37.185),(-122.1747,37.178),(-122.1742,37.173),(-122.1692,37.126),(-122.167792,37.11594),(-122.16757,37.11435),(-122.1671,37.111),(-122.1655,37.1),(-122.165169,37.09811),(-122.1641,37.092),(-122.1596,37.061),(-122.158381,37.05275),(-122.155991,37.03657),(-122.1531,37.017),(-122.1478,37.98),(-122.1407,37.932),(-122.1394,37.924),(-122.1389,37.92),(-122.1376,37.91)]                                                     | Oakland
  I- 880                             | [(-122.1755,37.185),(-122.1747,37.178),(-122.1742,37.173),(-122.1692,37.126),(-122.167792,37.11594),(-122.16757,37.11435),(-122.1671,37.111),(-122.1655,37.1),(-122.165169,37.09811),(-122.1641,37.092),(-122.1596,37.061),(-122.158381,37.05275),(-122.155991,37.03657),(-122.1531,37.017),(-122.1478,37.98),(-122.1407,37.932),(-122.1394,37.924),(-122.1389,37.92),(-122.1376,37.91)]                                                     | Berkeley
+ I- 880                             | [(-122.1755,37.185),(-122.1747,37.178),(-122.1742,37.173),(-122.1692,37.126),(-122.167792,37.11594),(-122.16757,37.11435),(-122.1671,37.111),(-122.1655,37.1),(-122.165169,37.09811),(-122.1641,37.092),(-122.1596,37.061),(-122.158381,37.05275),(-122.155991,37.03657),(-122.1531,37.017),(-122.1478,37.98),(-122.1407,37.932),(-122.1394,37.924),(-122.1389,37.92),(-122.1376,37.91)]                                                     | Oakland
  I- 880                             | [(-122.2214,37.711),(-122.2202,37.699),(-122.2199,37.695),(-122.219,37.682),(-122.2184,37.672),(-122.2173,37.652),(-122.2159,37.638),(-122.2144,37.616),(-122.2138,37.612),(-122.2135,37.609),(-122.212,37.592),(-122.2116,37.586),(-122.2111,37.581)]                                                                                                                                                                                       | Berkeley
  I- 880                             | [(-122.2707,37.975),(-122.2693,37.972),(-122.2681,37.966),(-122.267,37.962),(-122.2659,37.957),(-122.2648,37.952),(-122.2636,37.946),(-122.2625,37.935),(-122.2617,37.927),(-122.2607,37.921),(-122.2593,37.916),(-122.258,37.911),(-122.2536,37.898),(-122.2432,37.858),(-122.2408,37.845),(-122.2386,37.827),(-122.2374,37.811)]                                                                                                           | Berkeley
  I- 880                        Ramp | [(-122.0019,37.301),(-122.002,37.293)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
@@ -202,28 +215,28 @@ SELECT * FROM street;
  Laguna                        Ave  | [(-122.2099,37.989),(-122.2089,37)]                                                                                                                                                                                                                                                                                                                                                                                                          | Berkeley
  Laguna                        Ave  | [(-122.2099,37.989),(-122.2089,37)]                                                                                                                                                                                                                                                                                                                                                                                                          | Lafayette
  Lakehurst                     Cir  | [(-122.284729,37.89025),(-122.286096,37.90364)]                                                                                                                                                                                                                                                                                                                                                                                              | Berkeley
- Lakeshore                     Ave  | [(-122.2586,37.99),(-122.2556,37.006)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
  Lakeshore                     Ave  | [(-122.2586,37.99),(-122.2556,37.006)]                                                                                                                                                                                                                                                                                                                                                                                                       | Lafayette
+ Lakeshore                     Ave  | [(-122.2586,37.99),(-122.2556,37.006)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
  Las Positas                   Road | [(-121.764488,37.99199),(-121.75569,37.02022)]                                                                                                                                                                                                                                                                                                                                                                                               | Oakland
  Las Positas                   Road | [(-121.764488,37.99199),(-121.75569,37.02022)]                                                                                                                                                                                                                                                                                                                                                                                               | Oakland
- Linden                        St   | [(-122.2867,37.998),(-122.2864,37.008)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Linden                        St   | [(-122.2867,37.998),(-122.2864,37.008)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
+ Linden                        St   | [(-122.2867,37.998),(-122.2864,37.008)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Livermore                     Ave  | [(-121.7687,37.448),(-121.769,37.375)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Livermore                     Ave  | [(-121.7687,37.448),(-121.769,37.375)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Livermore                     Ave  | [(-121.772719,37.99085),(-121.7728,37.001)]                                                                                                                                                                                                                                                                                                                                                                                                  | Oakland
  Livermore                     Ave  | [(-121.772719,37.99085),(-121.7728,37.001)]                                                                                                                                                                                                                                                                                                                                                                                                  | Oakland
- Locust                        St   | [(-122.1606,37.007),(-122.1593,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Locust                        St   | [(-122.1606,37.007),(-122.1593,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
+ Locust                        St   | [(-122.1606,37.007),(-122.1593,37.987)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Logan                         Ct   | [(-122.0053,37.492),(-122.0061,37.484)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Magnolia                      St   | [(-122.0971,37.5),(-122.0962,37.484)]                                                                                                                                                                                                                                                                                                                                                                                                        | Oakland
  Mandalay                      Road | [(-122.2322,37.397),(-122.2321,37.403)]                                                                                                                                                                                                                                                                                                                                                                                                      | Lafayette
  Marin                         Ave  | [(-122.2741,37.894),(-122.272,37.901)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
  Martin Luther King Jr         Way  | [(-122.2712,37.608),(-122.2711,37.599)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Mattos                        Dr   | [(-122.0005,37.502),(-122.000898,37.49683)]                                                                                                                                                                                                                                                                                                                                                                                                  | Oakland
- Maubert                       Ave  | [(-122.1114,37.009),(-122.1096,37.995)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Maubert                       Ave  | [(-122.1114,37.009),(-122.1096,37.995)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
- McClure                       Ave  | [(-122.1431,37.001),(-122.1436,37.998)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
+ Maubert                       Ave  | [(-122.1114,37.009),(-122.1096,37.995)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  McClure                       Ave  | [(-122.1431,37.001),(-122.1436,37.998)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
+ McClure                       Ave  | [(-122.1431,37.001),(-122.1436,37.998)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Medlar                        Dr   | [(-122.0627,37.378),(-122.0625,37.375)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Mildred                       Ct   | [(-122.0002,37.388),(-121.9998,37.386)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Miller                        Road | [(-122.0902,37.645),(-122.0865,37.545)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
@@ -242,8 +255,8 @@ SELECT * FROM street;
  Parkridge                     Dr   | [(-122.1438,37.884),(-122.1428,37.9)]                                                                                                                                                                                                                                                                                                                                                                                                        | Berkeley
  Parkside                      Dr   | [(-122.0475,37.603),(-122.0443,37.596)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Paseo Padre                   Pkwy | [(-121.9143,37.005),(-121.913522,37)]                                                                                                                                                                                                                                                                                                                                                                                                        | Oakland
- Paseo Padre                   Pkwy | [(-122.0021,37.639),(-121.996,37.628)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Paseo Padre                   Pkwy | [(-122.0021,37.639),(-121.996,37.628)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
+ Paseo Padre                   Pkwy | [(-122.0021,37.639),(-121.996,37.628)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Pearl                         St   | [(-122.2383,37.594),(-122.2366,37.615)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Periwinkle                    Road | [(-122.0451,37.301),(-122.044758,37.29844)]                                                                                                                                                                                                                                                                                                                                                                                                  | Oakland
  Pimlico                       Dr   | [(-121.8616,37.998),(-121.8618,37.008)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
@@ -254,11 +267,11 @@ SELECT * FROM street;
  Railroad                      Ave  | [(-122.0245,37.013),(-122.0234,37.003),(-122.0223,37.993)]                                                                                                                                                                                                                                                                                                                                                                                   | Oakland
  Railroad                      Ave  | [(-122.0245,37.013),(-122.0234,37.003),(-122.0223,37.993)]                                                                                                                                                                                                                                                                                                                                                                                   | Berkeley
  Ranspot                       Dr   | [(-122.0972,37.999),(-122.0959,37)]                                                                                                                                                                                                                                                                                                                                                                                                          | Oakland
- Ranspot                       Dr   | [(-122.0972,37.999),(-122.0959,37)]                                                                                                                                                                                                                                                                                                                                                                                                          | Oakland
  Ranspot                       Dr   | [(-122.0972,37.999),(-122.0959,37)]                                                                                                                                                                                                                                                                                                                                                                                                          | Berkeley
+ Ranspot                       Dr   | [(-122.0972,37.999),(-122.0959,37)]                                                                                                                                                                                                                                                                                                                                                                                                          | Oakland
  Redding                       St   | [(-122.1978,37.901),(-122.1975,37.895)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
- Redwood                       Road | [(-122.1493,37.98),(-122.1437,37.001)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Redwood                       Road | [(-122.1493,37.98),(-122.1437,37.001)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
+ Redwood                       Road | [(-122.1493,37.98),(-122.1437,37.001)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
  Roca                          Dr   | [(-122.0335,37.609),(-122.0314,37.599)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Rosedale                      Ct   | [(-121.9232,37.9),(-121.924,37.897)]                                                                                                                                                                                                                                                                                                                                                                                                         | Oakland
  Sacramento                    St   | [(-122.2799,37.606),(-122.2797,37.597)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
@@ -266,8 +279,8 @@ SELECT * FROM street;
  Saginaw                       Ct   | [(-121.8803,37.898),(-121.8806,37.901)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  San Andreas                   Dr   | [(-122.0609,37.9),(-122.0614,37.895)]                                                                                                                                                                                                                                                                                                                                                                                                        | Berkeley
  Santa Maria                   Ave  | [(-122.0773,37),(-122.0773,37.98)]                                                                                                                                                                                                                                                                                                                                                                                                           | Oakland
- Santa Maria                   Ave  | [(-122.0773,37),(-122.0773,37.98)]                                                                                                                                                                                                                                                                                                                                                                                                           | Oakland
  Santa Maria                   Ave  | [(-122.0773,37),(-122.0773,37.98)]                                                                                                                                                                                                                                                                                                                                                                                                           | Berkeley
+ Santa Maria                   Ave  | [(-122.0773,37),(-122.0773,37.98)]                                                                                                                                                                                                                                                                                                                                                                                                           | Oakland
  Shattuck                      Ave  | [(-122.2686,37.904),(-122.2686,37.897)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Sheridan                      Road | [(-122.2279,37.425),(-122.2253,37.411),(-122.2223,37.377)]                                                                                                                                                                                                                                                                                                                                                                                   | Lafayette
  Shoreline                     Dr   | [(-122.2657,37.603),(-122.2648,37.6)]                                                                                                                                                                                                                                                                                                                                                                                                        | Berkeley
@@ -317,27 +330,14 @@ SELECT * FROM street;
  Welch Creek                   Road | [(-121.7695,37.386),(-121.7737,37.413)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  West Loop                     Road | [(-122.0576,37.604),(-122.0602,37.586)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
  Western Pacific Railroad Spur      | [(-122.0394,37.018),(-122.0394,37.961)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- Western Pacific Railroad Spur      | [(-122.0394,37.018),(-122.0394,37.961)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Western Pacific Railroad Spur      | [(-122.0394,37.018),(-122.0394,37.961)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
+ Western Pacific Railroad Spur      | [(-122.0394,37.018),(-122.0394,37.961)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Whitlock Creek                     | [(-121.74683,37.91276),(-121.733107,37)]                                                                                                                                                                                                                                                                                                                                                                                                     | Oakland
  Whitlock Creek                     | [(-121.74683,37.91276),(-121.733107,37)]                                                                                                                                                                                                                                                                                                                                                                                                     | Oakland
  Willimet                      Way  | [(-122.0964,37.517),(-122.0949,37.493)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
  Wisconsin                     St   | [(-122.1994,37.017),(-122.1975,37.998),(-122.1971,37.994)]                                                                                                                                                                                                                                                                                                                                                                                   | Oakland
  Wisconsin                     St   | [(-122.1994,37.017),(-122.1975,37.998),(-122.1971,37.994)]                                                                                                                                                                                                                                                                                                                                                                                   | Berkeley
  Wp Railroad                        | [(-122.254,37.902),(-122.2506,37.891)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
- 100th                         Ave  | [(-122.1657,37.429),(-122.1647,37.432)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- 107th                         Ave  | [(-122.1555,37.403),(-122.1531,37.41)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
- 14th                          St   | [(-122.299,37.147),(-122.3,37.148)]                                                                                                                                                                                                                                                                                                                                                                                                          | Lafayette
- 19th                          Ave  | [(-122.2366,37.897),(-122.2359,37.905)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
- 1st                           St   | [(-121.75508,37.89294),(-121.753581,37.90031)]                                                                                                                                                                                                                                                                                                                                                                                               | Oakland
- 5th                           St   | [(-122.278,37),(-122.2792,37.005),(-122.2803,37.009)]                                                                                                                                                                                                                                                                                                                                                                                        | Lafayette
- 5th                           St   | [(-122.296,37.615),(-122.2953,37.598)]                                                                                                                                                                                                                                                                                                                                                                                                       | Berkeley
- 82nd                          Ave  | [(-122.1695,37.596),(-122.1681,37.603)]                                                                                                                                                                                                                                                                                                                                                                                                      | Berkeley
- 85th                          Ave  | [(-122.1877,37.466),(-122.186,37.476)]                                                                                                                                                                                                                                                                                                                                                                                                       | Oakland
- 89th                          Ave  | [(-122.1822,37.459),(-122.1803,37.471)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- 98th                          Ave  | [(-122.1568,37.498),(-122.1558,37.502)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- 98th                          Ave  | [(-122.1693,37.438),(-122.1682,37.444)]                                                                                                                                                                                                                                                                                                                                                                                                      | Oakland
- 98th                          Ave  | [(-122.2001,37.258),(-122.1974,37.27)]                                                                                                                                                                                                                                                                                                                                                                                                       | Lafayette
 (333 rows)
 
 SELECT name, #thepath FROM iexit ORDER BY name COLLATE "C", 2;
diff --git a/src/test/regress/expected/txid.out b/src/test/regress/expected/txid.out
index 95ba66e95e..2ea4434f51 100644
--- a/src/test/regress/expected/txid.out
+++ b/src/test/regress/expected/txid.out
@@ -238,9 +238,11 @@ SELECT txid_snapshot '1:9223372036854775807:3';
 (1 row)
 
 SELECT txid_snapshot '1:9223372036854775808:3';
-ERROR:  invalid input syntax for type pg_snapshot: "1:9223372036854775808:3"
-LINE 1: SELECT txid_snapshot '1:9223372036854775808:3';
-                             ^
+      txid_snapshot      
+-------------------------
+ 1:9223372036854775808:3
+(1 row)
+
 -- test txid_current_if_assigned
 BEGIN;
 SELECT txid_current_if_assigned() IS NULL;
diff --git a/src/test/regress/expected/type_sanity.out b/src/test/regress/expected/type_sanity.out
index d3ac08c9ee..952019b2e2 100644
--- a/src/test/regress/expected/type_sanity.out
+++ b/src/test/regress/expected/type_sanity.out
@@ -19,7 +19,7 @@ WHERE t1.typnamespace = 0 OR
     (t1.typlen <= 0 AND t1.typlen != -1 AND t1.typlen != -2) OR
     (t1.typtype not in ('b', 'c', 'd', 'e', 'm', 'p', 'r')) OR
     NOT t1.typisdefined OR
-    (t1.typalign not in ('c', 's', 'i', 'd')) OR
+    (t1.typalign not in ('c', 's', 'i', 'd', 'x')) OR
     (t1.typstorage not in ('p', 'x', 'e', 'm'));
  oid | typname 
 -----+---------
@@ -32,7 +32,8 @@ WHERE t1.typbyval AND
     (t1.typlen != 1 OR t1.typalign != 'c') AND
     (t1.typlen != 2 OR t1.typalign != 's') AND
     (t1.typlen != 4 OR t1.typalign != 'i') AND
-    (t1.typlen != 8 OR t1.typalign != 'd');
+    (t1.typlen != 8 OR t1.typalign != 'd') AND
+    (t1.typlen != 8 OR t1.typalign != 'x');
  oid | typname 
 -----+---------
 (0 rows)
diff --git a/src/test/regress/expected/xid.out b/src/test/regress/expected/xid.out
index d8e76f3321..3252bdc28d 100644
--- a/src/test/regress/expected/xid.out
+++ b/src/test/regress/expected/xid.out
@@ -8,9 +8,9 @@ select '010'::xid,
 	   '42'::xid8,
 	   '0xffffffffffffffff'::xid8,
 	   '-1'::xid8;
- xid | xid |    xid     |    xid     | xid8 | xid8 |         xid8         |         xid8         
------+-----+------------+------------+------+------+----------------------+----------------------
-   8 |  42 | 4294967295 | 4294967295 |    8 |   42 | 18446744073709551615 | 18446744073709551615
+ xid | xid |    xid     |         xid          | xid8 | xid8 |         xid8         |         xid8         
+-----+-----+------------+----------------------+------+------+----------------------+----------------------
+   8 |  42 | 4294967295 | 18446744073709551615 |    8 |   42 | 18446744073709551615 | 18446744073709551615
 (1 row)
 
 -- garbage values are not yet rejected (perhaps they should be)
@@ -381,9 +381,11 @@ SELECT pg_snapshot '1:9223372036854775807:3';
 (1 row)
 
 SELECT pg_snapshot '1:9223372036854775808:3';
-ERROR:  invalid input syntax for type pg_snapshot: "1:9223372036854775808:3"
-LINE 1: SELECT pg_snapshot '1:9223372036854775808:3';
-                           ^
+       pg_snapshot       
+-------------------------
+ 1:9223372036854775808:3
+(1 row)
+
 -- test pg_current_xact_id_if_assigned
 BEGIN;
 SELECT pg_current_xact_id_if_assigned() IS NULL;
diff --git a/src/test/regress/expected/xid64.out b/src/test/regress/expected/xid64.out
new file mode 100644
index 0000000000..c30c5b5739
--- /dev/null
+++ b/src/test/regress/expected/xid64.out
@@ -0,0 +1,92 @@
+---
+--- Unit test for xid64 functions
+---
+-- directory paths and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+\set regresslib :libdir '/regress' :dlsuffix
+CREATE FUNCTION xid64_test_1(rel regclass) RETURNS VOID
+    AS :'regresslib', 'xid64_test_1' LANGUAGE C STRICT;
+CREATE FUNCTION xid64_test_2(rel regclass) RETURNS VOID
+    AS :'regresslib', 'xid64_test_2' LANGUAGE C STRICT;
+CREATE FUNCTION xid64_test_double_xmax(rel regclass) RETURNS VOID
+    AS :'regresslib', 'xid64_test_double_xmax' LANGUAGE C STRICT;
+---
+--- Check page consistency after conversion
+---
+CREATE UNLOGGED TABLE test_xid64_table(a int);
+ALTER TABLE test_xid64_table SET (autovacuum_enabled = false);
+INSERT INTO test_xid64_table(a) SELECT a FROM generate_series(1, 1000) AS a;
+SELECT xid64_test_1('test_xid64_table');
+INFO:  test 1: page is converted to xid64 format
+ xid64_test_1 
+--------------
+ 
+(1 row)
+
+DROP TABLE test_xid64_table;
+---
+--- Check tuples consistency after conversion
+---
+CREATE UNLOGGED TABLE test_xid64_table(s serial, i int, t text);
+ALTER TABLE test_xid64_table SET (autovacuum_enabled = false);
+DO $$
+BEGIN
+  FOR j IN 1..20 LOOP
+    INSERT INTO test_xid64_table(i, t) VALUES (random()::int, md5(random()::text));
+    COMMIT;
+  END LOOP;
+END $$;
+DO $$
+BEGIN
+  FOR j IN 1..10 LOOP
+    DELETE FROM test_xid64_table WHERE ctid IN (SELECT ctid FROM test_xid64_table TABLESAMPLE BERNOULLI (5));
+    COMMIT;
+  END LOOP;
+END $$;
+SELECT xid64_test_2('test_xid64_table');
+ xid64_test_2 
+--------------
+ 
+(1 row)
+
+DROP TABLE test_xid64_table;
+---
+--- Check tuples consistency after conversion to double xmax (on full page)
+---
+CREATE UNLOGGED TABLE test_xid64_table(i int);
+DO $$
+BEGIN
+  FOR j IN 1..40 LOOP
+    INSERT INTO test_xid64_table SELECT i FROM generate_series(1, 100) AS i;
+    COMMIT;
+  END LOOP;
+END $$;
+SELECT xid64_test_2('test_xid64_table');
+ xid64_test_2 
+--------------
+ 
+(1 row)
+
+DROP TABLE test_xid64_table;
+CREATE UNLOGGED TABLE test_xid64_table(i text);
+INSERT INTO test_xid64_table(i) VALUES ('NNBABCDSDFGHJKLP');
+DO $$
+BEGIN
+  FOR j IN 1..40 LOOP
+    INSERT INTO test_xid64_table(i) SELECT 'A' FROM generate_series(1, 100) AS i;
+    COMMIT;
+  END LOOP;
+END $$;
+SELECT xid64_test_double_xmax('test_xid64_table');
+INFO:  test double xmax: page 0 is converted into double xmax format
+INFO:  test double xmax: end
+ xid64_test_double_xmax 
+------------------------
+ 
+(1 row)
+
+DROP TABLE test_xid64_table;
+DROP FUNCTION xid64_test_1(rel regclass);
+DROP FUNCTION xid64_test_2(rel regclass);
+DROP FUNCTION xid64_test_double_xmax(rel regclass);
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index 103e11483d..456cd97440 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -33,7 +33,7 @@ test: strings numerology point lseg line box path polygon circle date time timet
 # geometry depends on point, lseg, line, box, path, polygon, circle
 # horology depends on date, time, timetz, timestamp, timestamptz, interval
 # ----------
-test: geometry horology tstypes regex type_sanity opr_sanity misc_sanity comments expressions unicode xid mvcc
+test: geometry horology tstypes regex type_sanity opr_sanity misc_sanity comments expressions unicode xid xid64 mvcc
 
 # ----------
 # Load huge amounts of data
diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c
index 982801e029..17cc8ea066 100644
--- a/src/test/regress/pg_regress.c
+++ b/src/test/regress/pg_regress.c
@@ -2267,7 +2267,7 @@ regression_main(int argc, char *argv[],
 		/* initdb */
 		header(_("initializing database system"));
 		snprintf(buf, sizeof(buf),
-				 "\"%s%sinitdb\" -D \"%s/data\" --no-clean --no-sync%s%s > \"%s/log/initdb.log\" 2>&1",
+				 "\"%s%sinitdb\" -D \"%s/data\" -x 1249835483136 -m 2422361554944 -o 3594887626752 --no-clean --no-sync%s%s > \"%s/log/initdb.log\" 2>&1",
 				 bindir ? bindir : "",
 				 bindir ? "/" : "",
 				 temp_instance,
diff --git a/src/test/regress/regress.c b/src/test/regress/regress.c
index ba3532a51e..e92a3e3c39 100644
--- a/src/test/regress/regress.c
+++ b/src/test/regress/regress.c
@@ -23,6 +23,7 @@
 #include "access/htup_details.h"
 #include "access/transam.h"
 #include "access/xact.h"
+#include "catalog/catalog.h"
 #include "catalog/namespace.h"
 #include "catalog/pg_operator.h"
 #include "catalog/pg_type.h"
@@ -1257,3 +1258,292 @@ get_columns_length(PG_FUNCTION_ARGS)
 
 	PG_RETURN_INT32(column_offset);
 }
+
+#include "access/hio.h"
+#include "access/relation.h"
+#include "storage/bufmgr.h"
+#include "utils/rel.h"
+
+static void
+CheckNewPage(char *msg, Page page)
+{
+	uint16			size;
+
+	if (PageGetPageLayoutVersion(page) != PG_PAGE_LAYOUT_VERSION)
+		elog(ERROR, "%s: page version is %d, expected %d ",
+			 msg, PageGetPageLayoutVersion(page), PG_PAGE_LAYOUT_VERSION);
+
+	size = PageGetSpecialSize(page);
+	if (size == MAXALIGN(sizeof(HeapPageSpecialData)))
+		elog(INFO, "%s: page is converted to xid64 format", msg);
+	else if (HeapPageIsDoubleXmax(page))
+		elog(INFO, "%s: page is converted into double xmax format", msg);
+	else
+		elog(ERROR, "%s: converted page has pageSpecial size %u, expected %llu",
+			 msg, size,
+			 (unsigned long long) MAXALIGN(sizeof(HeapPageSpecialData)));
+}
+
+/*
+ * Get page from relation.
+ * Make this page look like in 32-bit xid format.
+ * Convert it to 64-bit xid format.
+ * Run basic checks.
+ */
+PG_FUNCTION_INFO_V1(xid64_test_1);
+Datum
+xid64_test_1(PG_FUNCTION_ARGS)
+{
+	Oid					relid;
+	Relation			rel;
+	Buffer				buf;
+	Page				page;
+	PageHeader			hdr;
+
+	relid = PG_GETARG_OID(0);
+	rel = relation_open(relid, AccessExclusiveLock);
+	buf = ReadBuffer(rel, 0);
+	LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
+
+	page = BufferGetPage(buf);
+	hdr = (PageHeader) page;
+
+	if (PageGetSpecialSize(page) != MAXALIGN(sizeof(HeapPageSpecialData)))
+		elog(ERROR, "page expected in new format");
+
+	if (PageGetPageLayoutVersion(page) != PG_PAGE_LAYOUT_VERSION)
+		elog(ERROR, "unknown page version (%u)",
+			 PageGetPageLayoutVersion(page));
+
+	hdr->pd_special = BLCKSZ;
+	PageSetPageSizeAndVersion(page, BLCKSZ, PG_PAGE_LAYOUT_VERSION - 1);
+
+	convert_page(rel, page, buf, 0);
+	CheckNewPage("test 1", page);
+
+	UnlockReleaseBuffer(buf);
+	relation_close(rel, AccessExclusiveLock);
+
+	PG_RETURN_VOID();
+}
+
+typedef struct TupleCheckValues
+{
+	TransactionId		xmin;
+	TransactionId		xmax;
+} TupleCheckValues;
+
+typedef struct RelCheckValues
+{
+	TupleCheckValues   *tcv;
+	Size				ntuples;
+} RelCheckValues;
+
+static RelCheckValues
+FillRelCheckValues(Relation rel, Page page)
+{
+	RelCheckValues		set;
+	Size				n;
+
+#define DEFAULT_SET_SIZE 64
+	n = DEFAULT_SET_SIZE;
+	set.ntuples = 0;
+	set.tcv = palloc(sizeof(set.tcv[0]) * n);
+
+	{
+		OffsetNumber		maxoff,
+							offnum;
+		HeapTupleHeader		tuphdr;
+		ItemId				itemid;
+		HeapTupleData		tuple;
+		TransactionId		xmin,
+							xmax;
+
+		maxoff = PageGetMaxOffsetNumber(page);
+
+		for (offnum = FirstOffsetNumber;
+			 offnum <= maxoff;
+			 offnum = OffsetNumberNext(offnum))
+		{
+			itemid = PageGetItemId(page, offnum);
+			tuphdr = (HeapTupleHeader) PageGetItem(page, itemid);
+			tuple.t_data = tuphdr;
+			tuple.t_len = ItemIdGetLength(itemid);
+			tuple.t_tableOid = RelationGetRelid(rel);
+
+			if (HeapPageGetSpecial(page) == heapDoubleXmaxSpecial)
+			{
+				xmin = tuphdr->t_choice.t_heap.t_xmin;
+				xmax = tuphdr->t_choice.t_heap.t_xmax;
+			}
+			else
+			{
+				HeapTupleCopyBaseFromPage(&tuple, page, IsToastRelation(rel));
+
+				xmin = HeapTupleGetRawXmin(&tuple);
+				xmax = HeapTupleGetRawXmax(&tuple);
+			}
+
+			if (set.ntuples == n)
+			{
+				n *= 2;
+				set.tcv = repalloc(set.tcv, sizeof(set.tcv[0]) * n);
+			}
+
+			set.tcv[set.ntuples].xmin = xmin;
+			set.tcv[set.ntuples].xmax = xmax;
+			set.ntuples++;
+		}
+	}
+
+	return set;
+}
+
+/*
+ * Test xmin/xmax invariant when converting page from 32bit xid to 64xid.
+ *
+ * Scenario:
+ * - enforce all relation pages to 32bit xid format, discarding pd_xid_base and
+ *   pd_multi_base
+ * - store all xmin/xmax in array
+ * - convert all the pages from relation into 64xid format
+ * - store all new xmin/xmax in array
+ * - compare old and new xmin/xmax
+ *
+ * NOTE: inital xid value does not affect test as pd_xid_base/pd_multi_base
+ * discarded.
+ */
+PG_FUNCTION_INFO_V1(xid64_test_2);
+Datum
+xid64_test_2(PG_FUNCTION_ARGS)
+{
+	Oid					relid;
+	Relation			rel;
+	RelCheckValues		before,
+						after;
+	BlockNumber			pageno,
+						npages;
+	Size				i;
+
+	relid = PG_GETARG_OID(0);
+	rel = relation_open(relid, AccessExclusiveLock);
+	npages = RelationGetNumberOfBlocks(rel);
+
+	for (pageno = 0; pageno != npages; ++pageno)
+	{
+		Buffer			buf;
+		Page			page;
+		PageHeader		hdr;
+
+		/* get page */
+		buf = ReadBuffer(rel, pageno);
+		LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
+		page = BufferGetPage(buf);
+		hdr = (PageHeader) page;
+
+		/* make page look like 32-bit xid page */
+		hdr->pd_special = BLCKSZ;
+		PageSetPageSizeAndVersion(page, BLCKSZ, PG_PAGE_LAYOUT_VERSION - 1);
+
+		before = FillRelCheckValues(rel, page);
+		convert_page(rel, page, buf, pageno);
+		after = FillRelCheckValues(rel, page);
+
+		/* check */
+		if (before.ntuples != after.ntuples)
+			elog(ERROR, "numer of tuples must be equal");
+
+		for (i = 0; i != before.ntuples; ++i)
+		{
+			if (before.tcv[i].xmin != after.tcv[i].xmin && after.tcv[i].xmin)
+				elog(ERROR, "old and new xmin does not match (%llu != %llu)",
+					 (unsigned long long) before.tcv[i].xmin,
+					 (unsigned long long) after.tcv[i].xmin);
+
+			if (before.tcv[i].xmax != after.tcv[i].xmax)
+				elog(ERROR, "old and new xmax does not match (%llu != %llu)",
+					 (unsigned long long) before.tcv[i].xmax,
+					 (unsigned long long) after.tcv[i].xmax);
+		}
+
+		Assert(npages != 0);
+		pfree(before.tcv);
+		pfree(after.tcv);
+
+		UnlockReleaseBuffer(buf);
+	}
+
+	relation_close(rel, AccessExclusiveLock);
+
+	PG_RETURN_VOID();
+}
+
+PG_FUNCTION_INFO_V1(xid64_test_double_xmax);
+Datum
+xid64_test_double_xmax(PG_FUNCTION_ARGS)
+{
+	Oid					relid;
+	Relation			rel;
+	BlockNumber			pageno,
+						npages;
+	bool				found;
+
+	relid = PG_GETARG_OID(0);
+	rel = relation_open(relid, AccessExclusiveLock);
+	npages = RelationGetNumberOfBlocks(rel);
+	found = false;
+
+	for (pageno = 0; pageno != npages; ++pageno)
+	{
+		Buffer			buf;
+		Page			page;
+		PageHeader		hdr;
+		ItemId			itemid;
+		OffsetNumber 	offnum;
+		HeapTupleHeader	tuphdr;
+
+		buf = ReadBuffer(rel, pageno);
+		LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
+		page = BufferGetPage(buf);
+		hdr = (PageHeader) page;
+
+		if (pageno == 0)
+		{
+			itemid = PageGetItemId(page, FirstOffsetNumber);
+			itemid->lp_len += 16; /* Move to overlap special */
+		}
+
+		for (offnum = FirstOffsetNumber;
+			 offnum <= PageGetMaxOffsetNumber(page);
+			 offnum = OffsetNumberNext(offnum))
+		{
+			itemid = PageGetItemId(page, offnum);
+			tuphdr = (HeapTupleHeader) PageGetItem(page, itemid);
+			tuphdr->t_infomask |= HEAP_XMIN_COMMITTED;
+		}
+
+		hdr->pd_special = BLCKSZ;
+		PageSetPageSizeAndVersion(page, BLCKSZ, PG_PAGE_LAYOUT_VERSION - 1);
+
+		convert_page(rel, page, buf, pageno);
+
+		if (HeapPageIsDoubleXmax(page))
+		{
+			found = true;
+			elog(INFO, "test double xmax: page %u is converted into double xmax format",
+				 pageno);
+		}
+
+		UnlockReleaseBuffer(buf);
+	}
+
+	if (!found)
+		elog(ERROR, "test double xmax: failed, no double xmax");
+
+	Assert(npages != 0);
+	elog(INFO, "test double xmax: end");
+
+	relation_close(rel, AccessExclusiveLock);
+
+	PG_RETURN_VOID();
+}
diff --git a/src/test/regress/sql/indirect_toast.sql b/src/test/regress/sql/indirect_toast.sql
index 3e2f6c0237..ea087b5128 100644
--- a/src/test/regress/sql/indirect_toast.sql
+++ b/src/test/regress/sql/indirect_toast.sql
@@ -76,7 +76,18 @@ SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
 VACUUM FREEZE indtoasttest;
 SELECT substring(indtoasttest::text, 1, 200) FROM indtoasttest;
 
+create or replace function random_string(len integer) returns text as $$
+select substr((select string_agg(r,'') from (select random()::text as r from generate_series(1,(len+15)/16)) s1), 1, len);
+$$ language sql;
+
+create table toasttest_main(t text);
+alter table toasttest_main alter column t set storage main;
+
+insert into toasttest_main (select random_string(len) from generate_series(7000,8000) len);
+
 DROP TABLE indtoasttest;
+DROP TABLE toasttest_main;
 DROP FUNCTION update_using_indirect();
+DROP FUNCTION random_string(integer);
 
 RESET default_toast_compression;
diff --git a/src/test/regress/sql/insert.sql b/src/test/regress/sql/insert.sql
index bdcffd0314..7ada0801eb 100644
--- a/src/test/regress/sql/insert.sql
+++ b/src/test/regress/sql/insert.sql
@@ -55,7 +55,7 @@ INSERT INTO large_tuple_test (select 3, NULL);
 
 -- now this tuple won't fit on the second page, but the insert should
 -- still succeed by extending the relation
-INSERT INTO large_tuple_test (select 4, repeat('a', 8126));
+INSERT INTO large_tuple_test (select 4, repeat('a', 8112));
 
 DROP TABLE large_tuple_test;
 
@@ -597,3 +597,18 @@ alter table returningwrtest2 drop c;
 alter table returningwrtest attach partition returningwrtest2 for values in (2);
 insert into returningwrtest values (2, 'foo') returning returningwrtest;
 drop table returningwrtest;
+
+-- Check for MaxHeapTupleSize
+create table maxheaptuplesize_test(value text);
+alter table maxheaptuplesize_test alter column value set storage external;
+insert into maxheaptuplesize_test values (repeat('x', 8104));
+insert into maxheaptuplesize_test values (repeat('x', 8112));
+insert into maxheaptuplesize_test values (repeat('x', 8120));
+insert into maxheaptuplesize_test values (repeat('x', 8128));
+insert into maxheaptuplesize_test values (repeat('x', 8136));
+insert into maxheaptuplesize_test values (repeat('x', 8144));
+insert into maxheaptuplesize_test values (repeat('x', 8152));
+insert into maxheaptuplesize_test values (repeat('x', 8160));
+insert into maxheaptuplesize_test values (repeat('x', 8168));
+insert into maxheaptuplesize_test values (repeat('x', 8176));
+drop table maxheaptuplesize_test;
diff --git a/src/test/regress/sql/select_views.sql b/src/test/regress/sql/select_views.sql
index e742f13699..70e663e350 100644
--- a/src/test/regress/sql/select_views.sql
+++ b/src/test/regress/sql/select_views.sql
@@ -3,7 +3,7 @@
 -- test the views defined in CREATE_VIEWS
 --
 
-SELECT * FROM street;
+SELECT * FROM street ORDER BY name COLLATE "C", thepath::text COLLATE "C";
 
 SELECT name, #thepath FROM iexit ORDER BY name COLLATE "C", 2;
 
diff --git a/src/test/regress/sql/type_sanity.sql b/src/test/regress/sql/type_sanity.sql
index 5edc1f1f6e..2b6c4aff6c 100644
--- a/src/test/regress/sql/type_sanity.sql
+++ b/src/test/regress/sql/type_sanity.sql
@@ -22,7 +22,7 @@ WHERE t1.typnamespace = 0 OR
     (t1.typlen <= 0 AND t1.typlen != -1 AND t1.typlen != -2) OR
     (t1.typtype not in ('b', 'c', 'd', 'e', 'm', 'p', 'r')) OR
     NOT t1.typisdefined OR
-    (t1.typalign not in ('c', 's', 'i', 'd')) OR
+    (t1.typalign not in ('c', 's', 'i', 'd', 'x')) OR
     (t1.typstorage not in ('p', 'x', 'e', 'm'));
 
 -- Look for "pass by value" types that can't be passed by value.
@@ -33,7 +33,8 @@ WHERE t1.typbyval AND
     (t1.typlen != 1 OR t1.typalign != 'c') AND
     (t1.typlen != 2 OR t1.typalign != 's') AND
     (t1.typlen != 4 OR t1.typalign != 'i') AND
-    (t1.typlen != 8 OR t1.typalign != 'd');
+    (t1.typlen != 8 OR t1.typalign != 'd') AND
+    (t1.typlen != 8 OR t1.typalign != 'x');
 
 -- Look for "toastable" types that aren't varlena.
 
diff --git a/src/test/regress/sql/xid64.sql b/src/test/regress/sql/xid64.sql
new file mode 100644
index 0000000000..caa97a0ed9
--- /dev/null
+++ b/src/test/regress/sql/xid64.sql
@@ -0,0 +1,84 @@
+---
+--- Unit test for xid64 functions
+---
+
+-- directory paths and dlsuffix are passed to us in environment variables
+\getenv libdir PG_LIBDIR
+\getenv dlsuffix PG_DLSUFFIX
+
+\set regresslib :libdir '/regress' :dlsuffix
+
+CREATE FUNCTION xid64_test_1(rel regclass) RETURNS VOID
+    AS :'regresslib', 'xid64_test_1' LANGUAGE C STRICT;
+CREATE FUNCTION xid64_test_2(rel regclass) RETURNS VOID
+    AS :'regresslib', 'xid64_test_2' LANGUAGE C STRICT;
+CREATE FUNCTION xid64_test_double_xmax(rel regclass) RETURNS VOID
+    AS :'regresslib', 'xid64_test_double_xmax' LANGUAGE C STRICT;
+
+---
+--- Check page consistency after conversion
+---
+CREATE UNLOGGED TABLE test_xid64_table(a int);
+ALTER TABLE test_xid64_table SET (autovacuum_enabled = false);
+INSERT INTO test_xid64_table(a) SELECT a FROM generate_series(1, 1000) AS a;
+SELECT xid64_test_1('test_xid64_table');
+DROP TABLE test_xid64_table;
+
+---
+--- Check tuples consistency after conversion
+---
+CREATE UNLOGGED TABLE test_xid64_table(s serial, i int, t text);
+ALTER TABLE test_xid64_table SET (autovacuum_enabled = false);
+
+DO $$
+BEGIN
+  FOR j IN 1..20 LOOP
+    INSERT INTO test_xid64_table(i, t) VALUES (random()::int, md5(random()::text));
+    COMMIT;
+  END LOOP;
+END $$;
+
+DO $$
+BEGIN
+  FOR j IN 1..10 LOOP
+    DELETE FROM test_xid64_table WHERE ctid IN (SELECT ctid FROM test_xid64_table TABLESAMPLE BERNOULLI (5));
+    COMMIT;
+  END LOOP;
+END $$;
+
+SELECT xid64_test_2('test_xid64_table');
+DROP TABLE test_xid64_table;
+
+---
+--- Check tuples consistency after conversion to double xmax (on full page)
+---
+CREATE UNLOGGED TABLE test_xid64_table(i int);
+
+DO $$
+BEGIN
+  FOR j IN 1..40 LOOP
+    INSERT INTO test_xid64_table SELECT i FROM generate_series(1, 100) AS i;
+    COMMIT;
+  END LOOP;
+END $$;
+
+SELECT xid64_test_2('test_xid64_table');
+DROP TABLE test_xid64_table;
+
+CREATE UNLOGGED TABLE test_xid64_table(i text);
+INSERT INTO test_xid64_table(i) VALUES ('NNBABCDSDFGHJKLP');
+
+DO $$
+BEGIN
+  FOR j IN 1..40 LOOP
+    INSERT INTO test_xid64_table(i) SELECT 'A' FROM generate_series(1, 100) AS i;
+    COMMIT;
+  END LOOP;
+END $$;
+
+SELECT xid64_test_double_xmax('test_xid64_table');
+DROP TABLE test_xid64_table;
+
+DROP FUNCTION xid64_test_1(rel regclass);
+DROP FUNCTION xid64_test_2(rel regclass);
+DROP FUNCTION xid64_test_double_xmax(rel regclass);
diff --git a/src/test/xid-64/Makefile b/src/test/xid-64/Makefile
new file mode 100644
index 0000000000..3b1e50dfc0
--- /dev/null
+++ b/src/test/xid-64/Makefile
@@ -0,0 +1,22 @@
+#-------------------------------------------------------------------------
+#
+# Makefile for src/test/xid-64
+#
+# Copyright (c) 2018, Postgres Professional
+#
+# src/test/xid-64/Makefile
+#
+#-------------------------------------------------------------------------
+
+subdir = src/test/xid-64
+top_builddir = ../../..
+include $(top_builddir)/src/Makefile.global
+
+check:
+	$(prove_check)
+
+installcheck:
+	$(prove_installcheck)
+
+clean distclean maintainer-clean:
+	rm -rf tmp_check
diff --git a/src/test/xid-64/README b/src/test/xid-64/README
new file mode 100644
index 0000000000..01c0a1a1f7
--- /dev/null
+++ b/src/test/xid-64/README
@@ -0,0 +1,16 @@
+src/test/xid-64/README
+
+Regression tests for 64-bit XIDs
+=============================================
+
+This directory contains a test suite for 64-bit xids.
+
+Running the tests
+=================
+
+    make check
+
+NOTE: This creates a temporary installation, and some tests may
+create one or multiple nodes.
+
+NOTE: This requires the --enable-tap-tests argument to configure.
diff --git a/src/test/xid-64/t/001_test_large_xids.pl b/src/test/xid-64/t/001_test_large_xids.pl
new file mode 100644
index 0000000000..4c7dbc6cb1
--- /dev/null
+++ b/src/test/xid-64/t/001_test_large_xids.pl
@@ -0,0 +1,54 @@
+# Tests for large xid values
+use strict;
+use warnings;
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+use bigint;
+
+sub command_output
+{
+	my ($cmd) = @_;
+	my ($stdout, $stderr);
+	print("# Running: " . join(" ", @{$cmd}) . "\n");
+	my $result = IPC::Run::run $cmd, '>', \$stdout, '2>', \$stderr;
+	ok($result, "@$cmd exit code 0");
+	is($stderr, '', "@$cmd no stderr");
+	return $stdout;
+}
+
+my $START_VAL = 2**32;
+my $MAX_VAL = 2**62;
+
+my $ixid = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+my $imxid = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+my $imoff = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+
+# Initialize master node with the random xid-related parameters
+my $node = PostgreSQL::Test::Cluster->new('master');
+$node->init(extra => [ "--xid=$ixid", "--multixact-id=$imxid", "--multixact-offset=$imoff" ]);
+$node->start;
+
+# Initialize master node and check the xid-related parameters
+my $pgcd_output = command_output(
+	[ 'pg_controldata', '-D', $node->data_dir ] );
+print($pgcd_output); print('\n');
+ok($pgcd_output =~ qr/Latest checkpoint's NextXID:\s*(\d+)/, "XID found");
+my ($nextxid) = ($1);
+ok($nextxid >= $ixid && $nextxid < $ixid + 1000,
+	"Latest checkpoint's NextXID ($nextxid) is close to the initial xid ($ixid).");
+ok($pgcd_output =~ qr/Latest checkpoint's NextMultiXactId:\s*(\d+)/, "MultiXactId found");
+my ($nextmxid) = ($1);
+ok($nextmxid >= $imxid && $nextmxid < $imxid + 1000,
+	"Latest checkpoint's NextMultiXactId ($nextmxid) is close to the initial multiXactId ($imxid).");
+ok($pgcd_output =~ qr/Latest checkpoint's NextMultiOffset:\s*(\d+)/, "MultiOffset found");
+my ($nextmoff) = ($1);
+ok($nextmoff >= $imoff && $nextmoff < $imoff + 1000,
+	"Latest checkpoint's NextMultiOffset ($nextmoff) is close to the initial multiOffset ($imoff).");
+
+# Run pgbench to check whether the database is working properly
+$node->command_ok(
+	[ qw(pgbench --initialize --no-vacuum --scale=10) ],
+	  'pgbench finished without errors');
+
+done_testing();
\ No newline at end of file
diff --git a/src/test/xid-64/t/002_test_gucs.pl b/src/test/xid-64/t/002_test_gucs.pl
new file mode 100644
index 0000000000..ff9f2f3052
--- /dev/null
+++ b/src/test/xid-64/t/002_test_gucs.pl
@@ -0,0 +1,79 @@
+# Tests for guc boundary values
+use strict;
+use warnings;
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+use bigint;
+
+sub command_output
+{
+	my ($cmd) = @_;
+	my ($stdout, $stderr);
+	print("# Running: " . join(" ", @{$cmd}) . "\n");
+	my $result = IPC::Run::run $cmd, '>', \$stdout, '2>', \$stderr;
+	ok($result, "@$cmd exit code 0");
+	is($stderr, '', "@$cmd no stderr");
+	return $stdout;
+}
+
+sub set_guc
+{
+	my ($node, $guc, $val) = @_;
+	print("SET $guc = $val\n");
+	$node->safe_psql('postgres', "ALTER SYSTEM SET $guc = $val");
+	$node->restart();
+}
+
+sub test_pgbench
+{
+	my ($node) = @_;
+	$node->command_ok(
+		[ qw(pgbench --progress=5 --transactions=1000 --jobs=5 --client=5) ],
+		  'pgbench finished without errors');
+}
+
+my @guc_vals = (
+	[ "autovacuum_freeze_max_age", 100000, 2**63 - 1 ],
+	[ "autovacuum_multixact_freeze_max_age", 10000, 2**63 - 1 ],
+	[ "vacuum_freeze_min_age", 0, 2**63 - 1 ],
+	[ "vacuum_freeze_table_age", 0, 2**63 - 1 ],
+	[ "vacuum_multixact_freeze_min_age", 0, 2**63 - 1 ],
+	[ "vacuum_multixact_freeze_table_age", 0, 2**63 -1 ]
+);
+
+my $START_VAL = 2**32;
+my $MAX_VAL = 2**62;
+
+my $ixid = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+my $imxid = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+my $imoff = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+
+# Initialize master node
+my $node = PostgreSQL::Test::Cluster->new('master');
+$node->init(extra => [ "--xid=$ixid", "--multixact-id=$imxid", "--multixact-offset=$imoff" ]);
+# Disable logging of all statements to avoid log bloat during pgbench
+$node->append_conf('postgresql.conf', "log_statement = none");
+$node->start;
+
+# Fill the test database with the pgbench data
+$node->command_ok(
+	[ qw(pgbench --initialize --scale=10) ],
+	  'pgbench finished without errors');
+
+# Test all GUCs with minimum, maximum and random value inbetween
+#  (run pgbench for every configuration setting)
+foreach my $gi (0 .. $#guc_vals) {
+	print($guc_vals[$gi][0]); print("\n");
+	my $guc = $guc_vals[$gi][0];
+	my $minval = $guc_vals[$gi][1];
+	my $maxval = $guc_vals[$gi][2];
+	set_guc($node, $guc, $minval);
+	test_pgbench($node);
+	set_guc($node, $guc, $maxval);
+	test_pgbench($node);
+	set_guc($node, $guc, $minval + int(rand($maxval - $minval)));
+	test_pgbench($node);
+}
+
+done_testing();
\ No newline at end of file
diff --git a/src/test/xid-64/t/003_test_integrity.pl b/src/test/xid-64/t/003_test_integrity.pl
new file mode 100644
index 0000000000..ca079f11cb
--- /dev/null
+++ b/src/test/xid-64/t/003_test_integrity.pl
@@ -0,0 +1,58 @@
+# Check integrity after dump/restore with different xids
+use strict;
+use warnings;
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+use File::Compare;
+
+my $tempdir = PostgreSQL::Test::Utils::tempdir;
+use bigint;
+
+my $START_VAL = 2**32;
+my $MAX_VAL = 2**62;
+
+my $ixid = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+my $imxid = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+my $imoff = $START_VAL + int(rand($MAX_VAL - $START_VAL));
+
+# Initialize master node
+my $node = PostgreSQL::Test::Cluster->new('master');
+$node->init();
+$node->start;
+
+# Create a database and fill it with the pgbench data
+$node->safe_psql('postgres', "CREATE DATABASE pgbench_db");
+$node->command_ok(
+	[ qw(pgbench --initialize --scale=2 pgbench_db) ],
+	  'pgbench finished without errors');
+# Dump the database (cluster the main table to put data in a determined order)
+$node->safe_psql('pgbench_db', qq(
+	CREATE INDEX pa_aid_idx ON pgbench_accounts (aid);
+	CLUSTER pgbench_accounts USING pa_aid_idx));
+$node->command_ok(
+	[ "pg_dump", "-w", "--inserts", "--file=$tempdir/pgbench.sql", "pgbench_db" ],
+	  'pgdump finished without errors');
+$node->stop('fast');
+
+# Initialize second node
+my $node2 = PostgreSQL::Test::Cluster->new('master2');
+$node2->init(extra => [ "--xid=$ixid", "--multixact-id=$imxid", "--multixact-offset=$imoff" ]);
+# Disable logging of all statements to avoid log bloat during restore
+$node2->append_conf('postgresql.conf', "log_statement = none");
+$node2->start;
+
+# Create a database and restore the previous dump
+$node2->safe_psql('postgres', "CREATE DATABASE pgbench_db");
+my $txid0 = $node2->safe_psql('pgbench_db', 'SELECT txid_current()');
+print("# Initial txid_current: $txid0\n");
+$node2->command_ok(["psql", "-q", "-f", "$tempdir/pgbench.sql", "pgbench_db"]);
+
+# Dump the database and compare the dumped content with the previous one
+$node2->safe_psql('pgbench_db', 'CLUSTER pgbench_accounts');
+$node2->command_ok(
+	[ "pg_dump", "-w", "--inserts", "--file=$tempdir/pgbench2.sql", "pgbench_db" ],
+	  'pgdump finished without errors');
+ok(File::Compare::compare_text("$tempdir/pgbench.sql", "$tempdir/pgbench2.sql") == 0, "no differences detected");
+
+done_testing();
\ No newline at end of file
diff --git a/src/test/xid-64/t/004_test_relminmxid.pl b/src/test/xid-64/t/004_test_relminmxid.pl
new file mode 100644
index 0000000000..e1f6e556e5
--- /dev/null
+++ b/src/test/xid-64/t/004_test_relminmxid.pl
@@ -0,0 +1,90 @@
+# Check integrity after dump/restore with different xids
+use strict;
+use warnings;
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+use bigint;
+
+my ($node, $rmm, $vacout);
+$node = PostgreSQL::Test::Cluster->new('master');
+$node->init(extra => [ "--xid=3", "--multixact-id=1", "--multixact-offset=0" ]);
+$node->append_conf('postgresql.conf', 'max_prepared_transactions = 2');
+$node->start;
+
+sub relminmxid
+{
+    my $rmm = $node->safe_psql("postgres", qq(
+        SELECT relminmxid
+        FROM pg_class
+        WHERE relname = 'foo';));
+    return $rmm + 0;
+}
+
+sub vacuum
+{
+    my ($rc, $stdout, $stderr) = $node->psql("postgres", "VACUUM foo;");
+    return $stdout.$stderr;
+}
+
+sub gen_multixact
+{
+    $node->safe_psql("postgres", qq(
+    BEGIN;
+        SELECT * FROM foo FOR KEY SHARE;
+    PREPARE TRANSACTION 'fooshare';
+    ));
+
+    my $xmax = $node->safe_psql("postgres", qq(
+        SELECT xmax FROM foo;
+    ));
+    isnt($xmax + 0, 0, "xmax not empty");
+
+    $node->safe_psql("postgres", qq(
+    BEGIN;
+        SELECT * FROM foo FOR KEY SHARE;
+    COMMIT;
+    COMMIT PREPARED 'fooshare';
+    ));
+
+    my $mxact = $node->safe_psql("postgres", qq(
+        SELECT xmax FROM foo;
+    ));
+    isnt($mxact + 0, 0, "mxact not empty");
+    cmp_ok($xmax, '>', $mxact, "xmax is greater than mxact");
+}
+
+# Initialize master node with the random xid-related parameters
+$node->safe_psql("postgres", "CREATE TABLE foo (a int); INSERT INTO foo VALUES (1);");
+
+is(relminmxid(), 1, "relminmxid is default");
+
+vacuum();
+is(relminmxid(), 1, "relminmxid is still default");
+
+gen_multixact();
+is(relminmxid(), 1, "relminmxid is still still default");
+
+unlike(vacuum(), qr/multixact.*before relminmxid/, "no relminmxid error");
+
+# No intentionally break relminmxid
+$node->safe_psql("postgres", qq(
+    UPDATE pg_class SET relminmxid = ((1::int8<<62) + 1)::text::xid
+    WHERE relname = 'foo'
+));
+cmp_ok(relminmxid(), '>', 2**62, "relminmxid broken (intentionally)");
+
+gen_multixact();
+like(vacuum(), qr/multixact.*before relminmxid/, "got relminmxid error");
+cmp_ok(relminmxid(), '>', 2**62, "relminmxid broken (still)");
+
+# Fix relminmxid by setting to default
+$node->safe_psql("postgres", qq(
+    UPDATE pg_class SET relminmxid = '1'
+    WHERE relname = 'foo'
+));
+is(relminmxid(), 1, "relminmxid is default again");
+
+unlike(vacuum(), qr/multixact.*before relminmxid/, "no relminmxid error again");
+
+done_testing();
diff --git a/src/test/xid-64/t/005_stream_subxact.pl b/src/test/xid-64/t/005_stream_subxact.pl
new file mode 100644
index 0000000000..1379af6816
--- /dev/null
+++ b/src/test/xid-64/t/005_stream_subxact.pl
@@ -0,0 +1,100 @@
+
+# Copyright (c) 2021, PostgreSQL Global Development Group
+
+# Test xids streaming of large transaction containing large subtransactions
+# near 32-bit boundary.
+#
+# Mostly it is a copy of 016_stream_subxact.pl, but with publisher xid inited
+# just before 32-bit boundary, so if xids are replicated as 32-bit values,
+# subscriber will get 0 xid value.
+use strict;
+use warnings;
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+# Create publisher node
+my $node_publisher = PostgreSQL::Test::Cluster->new('publisher');
+$node_publisher->init(allows_streaming => 'logical', extra => ['-x', '4294966545']);
+$node_publisher->append_conf('postgresql.conf',
+	'logical_decoding_work_mem = 64kB');
+$node_publisher->start;
+
+# Create subscriber node
+my $node_subscriber = PostgreSQL::Test::Cluster->new('subscriber');
+$node_subscriber->init(allows_streaming => 'logical');
+$node_subscriber->start;
+
+# Create some preexisting content on publisher
+$node_publisher->safe_psql('postgres',
+	"CREATE TABLE test_tab (a int primary key, b varchar)");
+$node_publisher->safe_psql('postgres',
+	"INSERT INTO test_tab VALUES (1, 'foo'), (2, 'bar')");
+
+# Setup structure on subscriber
+$node_subscriber->safe_psql('postgres',
+	"CREATE TABLE test_tab (a int primary key, b text, c timestamptz DEFAULT now(), d bigint DEFAULT 999)"
+);
+
+# Setup logical replication
+my $publisher_connstr = $node_publisher->connstr . ' dbname=postgres';
+$node_publisher->safe_psql('postgres',
+	"CREATE PUBLICATION tap_pub FOR TABLE test_tab");
+
+my $appname = 'tap_sub';
+$node_subscriber->safe_psql('postgres',
+	"CREATE SUBSCRIPTION tap_sub CONNECTION '$publisher_connstr application_name=$appname' PUBLICATION tap_pub WITH (streaming = on)"
+);
+
+$node_publisher->wait_for_catchup($appname);
+
+# Also wait for initial table sync to finish
+my $synced_query =
+  "SELECT count(1) = 0 FROM pg_subscription_rel WHERE srsubstate NOT IN ('r', 's');";
+$node_subscriber->poll_query_until('postgres', $synced_query)
+  or die "Timed out while waiting for subscriber to synchronize data";
+
+my $result =
+  $node_subscriber->safe_psql('postgres',
+	"SELECT count(*), count(c), count(d = 999) FROM test_tab");
+is($result, qq(2|2|2), 'check initial data was copied to subscriber');
+
+# Insert, update and delete enough rows to exceed 64kB limit.
+$node_publisher->safe_psql(
+	'postgres', q{
+BEGIN;
+INSERT INTO test_tab SELECT i, md5(i::text) FROM generate_series(    3,  500) s(i);
+UPDATE test_tab SET b = md5(b) WHERE mod(a,2) = 0;
+DELETE FROM test_tab WHERE mod(a,3) = 0;
+SAVEPOINT s1;
+INSERT INTO test_tab SELECT i, md5(i::text) FROM generate_series(501,  1000) s(i);
+UPDATE test_tab SET b = md5(b) WHERE mod(a,2) = 0;
+DELETE FROM test_tab WHERE mod(a,3) = 0;
+SAVEPOINT s2;
+INSERT INTO test_tab SELECT i, md5(i::text) FROM generate_series(1001,  1500) s(i);
+UPDATE test_tab SET b = md5(b) WHERE mod(a,2) = 0;
+DELETE FROM test_tab WHERE mod(a,3) = 0;
+SAVEPOINT s3;
+INSERT INTO test_tab SELECT i, md5(i::text) FROM generate_series(1501,  2000) s(i);
+UPDATE test_tab SET b = md5(b) WHERE mod(a,2) = 0;
+DELETE FROM test_tab WHERE mod(a,3) = 0;
+SAVEPOINT s4;
+INSERT INTO test_tab SELECT i, md5(i::text) FROM generate_series(2001, 2500) s(i);
+UPDATE test_tab SET b = md5(b) WHERE mod(a,2) = 0;
+DELETE FROM test_tab WHERE mod(a,3) = 0;
+COMMIT;
+});
+
+$node_publisher->wait_for_catchup($appname);
+
+$result =
+  $node_subscriber->safe_psql('postgres',
+	"SELECT count(*), count(c), count(d = 999) FROM test_tab");
+is($result, qq(1667|1667|1667),
+	'check data was copied to subscriber in streaming mode and extra columns contain local defaults'
+);
+
+$node_subscriber->stop;
+$node_publisher->stop;
+
+done_testing();
diff --git a/src/test/xid-64/t/006_zeropage.pl b/src/test/xid-64/t/006_zeropage.pl
new file mode 100644
index 0000000000..fd3ac3973f
--- /dev/null
+++ b/src/test/xid-64/t/006_zeropage.pl
@@ -0,0 +1,33 @@
+use strict;
+use warnings;
+
+use PostgreSQL::Test::Cluster;
+use PostgreSQL::Test::Utils;
+use Test::More;
+
+# Check  WAL for ZEROPAGE record.
+
+sub command_output
+{
+	my ($cmd) = @_;
+	my ($stdout, $stderr);
+	print("# Running: " . join(" ", @{$cmd}) . "\n");
+	my $result = IPC::Run::run $cmd, '>', \$stdout, '2>', \$stderr;
+	return $stdout;
+}
+
+my $node = PostgreSQL::Test::Cluster->new('main');
+$node->init(extra => [ "--xid=3", "--multixact-id=3", "--multixact-offset=0" ]);;
+$node->start;
+my $pgdata = $node->data_dir;
+my $xlogfilename0 = $node->safe_psql('postgres',
+	"SELECT pg_walfile_name(pg_current_wal_lsn())");
+#$node->command_like(
+#	[ 'pg_waldump', '-S', "$pgdata/pg_wal/$xlogfilename0" ],
+#	qr/ZEROPAGE/,
+#	'pg_waldump prints start timestamp');
+my $wd_output = command_output(
+    [ 'pg_waldump', "$pgdata/pg_wal/$xlogfilename0" ]);
+ok($wd_output =~ qr/ZEROPAGE page 0/, "ZEROPAGE found");
+
+done_testing();
diff --git a/src/tools/msvc/Solution.pm b/src/tools/msvc/Solution.pm
index 52ff56ba83..e4f15ab5b7 100644
--- a/src/tools/msvc/Solution.pm
+++ b/src/tools/msvc/Solution.pm
@@ -461,6 +461,7 @@ sub GenerateFiles
 		PACKAGE_TARNAME     => lc qq{"$package_name"},
 		PACKAGE_URL         => qq{"$package_url"},
 		PACKAGE_VERSION     => qq{"$package_version"},
+		XID_IS_64BIT		=> 1,
 		PG_INT128_TYPE      => undef,
 		PG_INT64_TYPE       => 'long long int',
 		PG_KRB_SRVNAM       => qq{"postgres"},
diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list
index 34a76ceb60..37bb775fdc 100644
--- a/src/tools/pgindent/typedefs.list
+++ b/src/tools/pgindent/typedefs.list
@@ -3366,8 +3366,8 @@ intset_internal_node
 intset_leaf_node
 intset_node
 intvKEY
-itemIdCompact
-itemIdCompactData
+ItemIdCompact
+ItemIdCompactData
 iterator
 jmp_buf
 join_search_hook_type
-- 
2.17.2 (Apple Git-113)

