From bca8b7f16a3e720794cb0afbdb3733be4f8d9c2c Mon Sep 17 00:00:00 2001 From: Simon Riggs Date: Wed, 16 Feb 2011 19:29:37 +0000 Subject: Hot Standby feedback for avoidance of cleanup conflicts on standby. Standby optionally sends back information about oldestXmin of queries which is then checked and applied to the WALSender's proc->xmin. GetOldestXmin() is modified slightly to agree with GetSnapshotData(), so that all backends on primary include WALSender within their snapshots. Note this does nothing to change the snapshot xmin on either master or standby. Feedback piggybacks on the standby reply message. vacuum_defer_cleanup_age is no longer used on standby, though parameter still exists on primary, since some use cases still exist. Simon Riggs, review comments from Fujii Masao, Heikki Linnakangas, Robert Haas --- src/backend/utils/misc/postgresql.conf.sample | 1 + 1 file changed, 1 insertion(+) (limited to 'src/backend/utils/misc/postgresql.conf.sample') diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index 3b00a032621..6726733235b 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -196,6 +196,7 @@ #hot_standby = off # "on" allows queries during recovery # (change requires restart) +#hot_standby_feedback = off # info from standby to prevent query conflicts #max_standby_archive_delay = 30s # max delay before canceling queries # when reading WAL from archive; # -1 allows indefinite delay -- cgit v1.2.3