I've been getting some backup failures when trying to back up a fairly large database. I've tried setting:
* vacuum_defer_cleanup_age very high on the master * hot_standby_feedback = on on the slave * max_standby_streaming_delay = 300s and max_standby_archive_delay = 300s on the slave
Nothing seems to stop it failing intermittently. The error I'm getting is below: pg_dump: Dumping the contents of table "impressions" failed: PQgetResult() failed. pg_dump: Error message from server: ERROR: canceling statement due to conflict with recovery DETAIL: User was holding a relation lock for too long. pg_dump: The command was: COPY public.impressions (id, ... ) TO stdout; The following system errors were returned: Errno::EPERM: Operation not permitted - 'pg_dump' returned exit code: 1