> Sorry, I wasn't clear. > > Autovacuum runs with default setting, I believe it's daily, or whenever it > feels like. > > When autovacuum was disabled, we had this problem once every 2 months. > > With autovacuum enabled, we had this problem once in every six month. It > seems autovacuum could only delay the event, but not prevent it.
The first steps are still the same: change the autovacuum settings to be more aggressive.
> On Fri, Aug 10, 2012 at 3:49 PM, François Beausoleil > <francois@teksol.info>wrote: > > > > > Le 2012-08-10 à 07:53, Laszlo Fogas a écrit : > > > We are running Postgres 8.3 on our production servers on Amazon EC2. > > > > > > We have a reoccurring problem of slowness initially in every 2 months, > > after enabling autovacuum every 6 months what only full vacuum can solve. > > It's kind of a problem as it requires 2hrs downtime and we want to avoid > > that. What we are doing now is moving to Postgres 9.1 as a desperate > > measure, but we would like to understand better the root cause of the > > problem. > > > > The usual solution is to run autovacuum *more* frequently, not less. It's > > not perfectly clear, but you say "after enabling autovacuum every 6 > > months". If that's the case, then it's much too long. autovacuum should be > > running hourly, if not more often. > > > > > > http://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server#autovacuum_max_fsm_pages.2C_max_fsm_relationstalks about running more frequently. > > > > Hope that helps! > > François Beausoleil
