Logging autovacuum and vacuum activities
Information about autovacuum activities is sent to the postgresql.log based
on the level specified in the rds.force_autovacuum_logging_level parameter.
Following are the values allowed for this parameter and the PostgreSQL versions for which that
value is the default setting:
-
disabled(PostgreSQL 10, PostgreSQL 9.6) -
debug5,debug4,debug3,debug2,debug1 -
info(PostgreSQL 12, PostgreSQL 11) -
notice -
warning(PostgreSQL 13 and above) -
error, log,fatal,panic
The rds.force_autovacuum_logging_level works with the
log_autovacuum_min_duration parameter. The
log_autovacuum_min_duration parameter's value is the threshold (in
milliseconds) above which autovacuum actions get logged. A setting of -1 logs
nothing, while a setting of 0 logs all actions. As with
rds.force_autovacuum_logging_level, default values for
log_autovacuum_min_duration are version dependent, as follows:
-
10000 ms– PostgreSQL 14, PostgreSQL 13, PostgreSQL 12, and PostgreSQL 11 -
(empty)– No default value for PostgreSQL 10 and PostgreSQL 9.6
We recommend that you set rds.force_autovacuum_logging_level to
WARNING. We also recommend that you set
log_autovacuum_min_duration to a value from 1000 to 5000. A setting of 5000
logs activity that takes longer than 5,000 milliseconds. Any setting other than -1 also logs
messages if the autovacuum action is skipped because of a conflicting lock or concurrently
dropped relations. For more information, see Automatic
Vacuuming
To troubleshoot issues, you can change the rds.force_autovacuum_logging_level
parameter to one of the debug levels, from debug1 up to debug5 for
the most verbose information. We recommend that you use debug settings for short periods of
time and for troubleshooting purposes only. To learn more, see When to log
Note
PostgreSQL allows the rds_superuser account to view autovacuum sessions in
pg_stat_activity. For example, you can identify and end an autovacuum session
that is blocking a command from running, or running slower than a manually issued vacuum
command.