# Logging autovacuum and vacuum activities
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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](https://www.postgresql.org/docs/current/runtime-config-autovacuum.html) in the PostgreSQL documentation. 

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](https://www.postgresql.org/docs/current/static/runtime-config-logging.html#RUNTIME-CONFIG-LOGGING-WHEN) in the PostgreSQL documentation. 

**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.