Horton

Avoid SnapshotResetXmin() during AtEOXact_Snapshot()

Simon Riggs <simon@2ndQuadrant.com>

View on postgr.es
Commit: 42b4b0b2413b9b472aaf2112a3bbfd80a6ab4dc5
Author: Simon Riggs <simon@2ndQuadrant.com>
Date: 2017-03-24T14:20:59Z
Releases: 10.0 
Avoid SnapshotResetXmin() during AtEOXact_Snapshot()

For normal commits and aborts we already reset PgXact->xmin
Avoiding touching highly contented shmem improves concurrent
performance.

Simon Riggs

Discussion: CANP8+jJdXE9b+b9F8CQT-LuxxO0PBCB-SZFfMVAdp+akqo4zfg@mail.gmail.com

Files

PathChange+/−
src/backend/access/transam/xact.c modified +3 −3
src/backend/utils/time/snapmgr.c modified +18 −3
src/include/utils/snapmgr.h modified +1 −1