Thread: pgsql: WAL-log inplace update before revealing it to other sessions.
WAL-log inplace update before revealing it to other sessions. A buffer lock won't stop a reader having already checked tuple visibility. If a vac_update_datfrozenid() and then a crash happened during inplace update of a relfrozenxid value, datfrozenxid could overtake relfrozenxid. That could lead to "could not access status of transaction" errors. Back-patch to v12 (all supported versions). In v14 and earlier, this also back-patches the assertion removal from commit 7fcf2faf9c7dd473208fd6d5565f88d7f733782b. Discussion: https://postgr.es/m/20240620012908.92.nmisch@google.com Branch ------ REL_13_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/1e74e31f3c93f01c2ddb1e2b25db23fb0533244c Modified Files -------------- src/backend/access/heap/README.tuplock | 4 +-- src/backend/access/heap/heapam.c | 58 +++++++++++++++++++++++++-------- src/backend/access/transam/xloginsert.c | 2 -- 3 files changed, 46 insertions(+), 18 deletions(-)