From 3390ef1b7be28eac24dd95af23a4a287e6e7b1a4 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Wed, 16 Mar 2022 15:35:16 +1300 Subject: Fix waiting in RegisterSyncRequest(). If we run out of space in the checkpointer sync request queue (which is hopefully rare on real systems, but common with very small buffer pool), we wait for it to drain. While waiting, we should report that as a wait event so that users know what is going on, and also handle postmaster death, since otherwise the loop might never terminate if the checkpointer has exited. Back-patch to 12. Although the problem exists in earlier releases too, the code is structured differently before 12 so I haven't gone any further for now, in the absence of field complaints. Reported-by: Andres Freund Reviewed-by: Andres Freund Discussion: https://postgr.es/m/20220226213942.nb7uvb2pamyu26dj%40alap3.anarazel.de --- doc/src/sgml/monitoring.sgml | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'doc/src') diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml index 8620aaddc79..71559442f0b 100644 --- a/doc/src/sgml/monitoring.sgml +++ b/doc/src/sgml/monitoring.sgml @@ -2254,6 +2254,11 @@ postgres 27093 0.0 0.0 30096 2752 ? Ss 11:34 0:00 postgres: ser Waiting during recovery when WAL data is not available from any source (pg_wal, archive or stream). + + RegisterSyncRequest + Waiting while sending synchronization requests to the + checkpointer, because the request queue is full. + VacuumDelay Waiting in a cost-based vacuum delay point. -- cgit v1.2.3