From 10fcfada235af6186c9474230483ab0fe5c9610d Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Tue, 17 Apr 2012 16:28:31 +0300 Subject: [PATCH] Don't wait for the commit record to be replicated if we wrote no WAL. When using synchronous replication, we waited for the commit record to be replicated, but if we our transaction didn't write any other WAL records, that's not required because we don't even flush the WAL locally to disk in that case. This lead to long waits when committing a transaction that only modified a temporary table. Bug spotted by Thom Brown. --- src/backend/access/transam/xact.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index 7bdf38636b5..901fff059a1 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -1141,7 +1141,8 @@ RecordTransactionCommit(void) * Note that at this stage we have marked clog, but still show as running * in the procarray and continue to hold locks. */ - SyncRepWaitForLSN(XactLastRecEnd); + if (wrote_xlog) + SyncRepWaitForLSN(XactLastRecEnd); /* Reset XactLastRecEnd until the next transaction writes something */ XactLastRecEnd.xrecoff = 0;