AJ Weber escribió: > On 1/23/2013 2:13 PM, Jeff Janes wrote: > >Scheduling a manual vacuum should be fine (but keep in mind that > >vacuum has very different default cost_delay settings than autovacuum > >does. If the server is completely idle that shouldn't matter, but if > >it is only mostly idle, you might want to throttle the IO a bit). But > >I certainly would not disable autovacuum without further evidence. If > >a table only needs to be vacuumed once a day and you preemptively do > >it at 3a.m., then autovac won't bother to do it itself during the day. > > So there is no point, but much risk, in also turning autovac off. > If I set autovacuum_max_workers = 1, will that effectively > single-thread it so I don't have two running at once? Maybe that'll > mitigate disk contention a little at least? If you have a single one, it will go three times as fast. If you want to make the whole thing go slower (i.e. cause less impact on your I/O system when running), crank up autovacuum_vacuum_cost_delay. -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
