diff options
| author | Simon Riggs | 2017-04-06 12:31:52 +0000 |
|---|---|---|
| committer | Simon Riggs | 2017-04-06 12:31:52 +0000 |
| commit | 6bad580d9e678a0b604883e14d8401d469b06566 (patch) | |
| tree | 44630ef43002b029704432f405ae2949081eb841 /src/include | |
| parent | fd01983594b7d2119653428e3b532578008c7065 (diff) | |
Avoid SnapshotResetXmin() during AtEOXact_Snapshot()
For normal commits and aborts we already reset PgXact->xmin,
so we can simply avoid running SnapshotResetXmin() twice.
During performance tests by Alexander Korotkov, diagnosis
by Andres Freund showed PgXact array as a bottleneck. After
manual analysis by me of the code paths that touch those
memory locations, I was able to identify extraneous code
in the main transaction commit path.
Avoiding touching highly contented shmem improves concurrent
performance slightly on all workloads, confirmed by tests
run by Ashutosh Sharma and Alexander Korotkov.
Simon Riggs
Discussion: CANP8+jJdXE9b+b9F8CQT-LuxxO0PBCB-SZFfMVAdp+akqo4zfg@mail.gmail.com
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/utils/snapmgr.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h index 86c48d9c8ef..2f8d4fd4a0c 100644 --- a/src/include/utils/snapmgr.h +++ b/src/include/utils/snapmgr.h @@ -85,7 +85,7 @@ extern void UnregisterSnapshotFromOwner(Snapshot snapshot, ResourceOwner owner); extern void AtSubCommit_Snapshot(int level); extern void AtSubAbort_Snapshot(int level); -extern void AtEOXact_Snapshot(bool isCommit); +extern void AtEOXact_Snapshot(bool isCommit, bool isPrepare); extern void ImportSnapshot(const char *idstr); extern bool XactHasExportedSnapshots(void); |