Tom Lane escribió: > Alvaro Herrera <alvhe...@commandprompt.com> writes: > > Tom Lane escribi�: > >> I believe the interpretation of autovacuum_naptime is that it should > >> examine each database that often, ie once a minute by default. So > >> it's got more than 30 databases per second to look through. > > > Note that this is correct in 8.1 and 8.2 but not 8.3 onwards. > > Oh? The current documentation still defines the variable thusly: > > Specifies the minimum delay between autovacuum runs on any given > database. In each round the daemon examines the database and > issues VACUUM and ANALYZE commands as needed for tables in that > database.
Sorry, it's the other way around actually -- correct for 8.3 onwards, wrong for 8.1 and 8.2. In the earlier versions, it would do one run in a chosen database, sleep during "naptime", then do another run. > I suppose the use of "minimum" means that this is not technically > incorrect, but it's sure not very helpful if there is some other > rule involved that causes it to not behave as I said. (And if there > is some other rule, what is that?) The word "minimum" is there because it's possible that all workers are busy with some other database(s). > Please improve the docs. I'll see about that. -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
