Date: Mon, 4 Jul 2005 10:27:55 -0400
From: Alvaro Herrera <alvherre@surnet.cl>
To: postgresql performance list <pgsql-performance@postgresql.org>
Subject: Re: plain inserts and deletes very slow
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On Mon, Jul 04, 2005 at 10:57:29AM +0200, Enrico Weigelt wrote:
> * Alvaro Herrera <alvherre@surnet.cl> wrote:
> > On Mon, Jul 04, 2005 at 02:17:47AM +0200, Enrico Weigelt wrote:
> > > * David Mitchell <david.mitchell@telogis.com> wrote:
> > > > Perhaps if you are doing a lot of inserts and deletes, vacuuming every 6 
> > > > minutes would be closer to your mark. Try vacuuming every 15 minutes for 
> > > > a start and see how that affects things (you will have to do a vacuum 
> > > > full to get the tables back into shape after them slowing down as they 
> > > > have).
> > > 
> > > hmm. I've just done vacuum full at the moment on these tables, but it 
> > > doesnt seem to change anything :(
> > 
> > Maybe you need a REINDEX, if you have indexes on that table.  Try that,
> > coupled with the frequent VACUUM suggestion.
> 
> I've tried it, but it doesn't seem to help :(

So, lets back up a little.  You have no table nor index bloat, because
you reindexed and full-vacuumed.  So where does the slowness come from?
Can you post an example EXPLAIN ANALYZE of the queries in question?

-- 
Alvaro Herrera (<alvherre[a]surnet.cl>)
"El realista sabe lo que quiere; el idealista quiere lo que sabe" (Anónimo)