On 8/9/24 03:26, Jim Vanns wrote:
Hi pggen community!
I am struggling with this error almost daily now and despite various
efforts, not succeeding in avoiding or dealing with it;
My questions are;
1) How should I be managing this? Although not new to PG, I am new to
this particular problem.
2) How can I confirm what processes/tables are contributing to this
multixact "members" limit?
3) What are the units for
vacuum_multixact_freeze_min_age/vacuum_multixact_freeze_table_age and
how should I be
setting them appropriately for my rates etc.? I can't really find
anything that explains this clearly.
4) How can I check that autovacuum workers are specifically able to
freeze multixact XIDs and thus avoid this?
pg_stat_activity
https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-ACTIVITY-VIEW
wait_event_type
wait_event
Table 28.12. Wait Events of Type LWLock
This might tell you if something is hanging up on a table or tables.
5) Can I check if autovacuum is actually succeeding in its work
pg_stat_all_tables
https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-ALL-TABLES-VIEW
Will show you the vacuum/analyze that has been done on a table.
Jim Vanns
Principal Production Engineer
Industrial Light & Magic, London
--
Adrian Klaver
adrian.klaver@xxxxxxxxxxx
