Re: Why so slow?

"Jim C. Nasby" <jnasby(at)pervasive(dot)com> wrote:

> On Sun, Apr 30, 2006 at 10:03:46AM -0400, Bill Moran wrote:
> > At this point, it seems like you need to do 2 things:
> > 1) Schedule lazy vacuum to run, or configure autovacuum.
> > 2) Schedule some downtime to run "vacuum full" to recover some disk space.
> >
> > #2 only needs done once to get you back on track, assuming that #1 is
> > done properly.
>
> You'll also want to reindex since vacuum full won't clean the indexes
> up. You might also want to read
> http://www.pervasivepostgres.com/instantkb13/article.aspx?id=10087 and
> http://www.pervasivepostgres.com/instantkb13/article.aspx?id=10116.

Reindexing is in a different class than vacuuming. Neglecting to vacuum
creates a problem that gets worse and worse as time goes on. Neglecting
to reindex does not create an infinately growing problem, since empty
index pages are recycled automatically. It's also conceivable that some
usage patterns don't need to reindex at all.

http://www.postgresql.org/docs/8.1/interactive/routine-reindex.html

--
Bill Moran
Potential Technologies
http://www.potentialtech.com