Re: slowness what only full vacuum can solve

On Fri, 10 Aug 2012 16:14:54 +0200 Laszlo Fogas <laszlo(at)falconsocial(dot)com> wrote:

> 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(at)teksol(dot)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

--
Bill Moran <wmoran(at)potentialtech(dot)com>