On Sun, May 1, 2016 at 10:39 PM, McCoy, Shawn <shamc...@amazon.com> wrote: > I have been debugging a problem on a 9.3.10 Postgres database cluster with > over 1200 databases. 10 workers, increased maintenance_work_mem, auto > vacuum settings to run more frequently than default. What I will notice is > that autovacuum will run for a week or so and traverse databases as > expected. I will be able to see that age(datfrozenxid) for all 1200 > databases will stay close to autovacuum_freeze_max_age as desired. > > Then, suddenly I will see it get “stuck”. Autovacuum launcher will not > launch worker processes even though databases start to age past > autovacuum_freeze_max_age. If I create a list of databases and sort by > age(datfrozenxid), connect to the database with the oldest and execute a > simple: "vacuum freeze pg_database;”, autovacuum springs back into action. > > It’s never the same database where autovacuum seems to get “stuck”. I’m > attempting to gather more debugging information, but, also can’t understand > why simply doing a “vacuum freeze pg_database” breaks up the jam. > > Any thoughts?
So when it's stuck, there are no AV worker processes running at all, for a sustained period of time? -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
