Thread: pgsql: Keep heavily-contended fields in XLogCtlInsert on different cach

Keep heavily-contended fields in XLogCtlInsert on different cache lines.

Performance testing shows that if the insertpos_lck spinlock and the fields
that it protects are on the same cache line with other variables that are
frequently accessed, the false sharing can hurt performance a lot. Keep
them apart by adding some padding.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/375d8526f2900d0c377f44532f6d09ee06531f67

Modified Files
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src/backend/access/transam/xlog.c |   15 ++++++++++++---
src/include/pg_config_manual.h    |   11 +++++++++++
2 files changed, 23 insertions(+), 3 deletions(-)