Re: postgresql meltdown on PlanetMath.org

> >> A "select count(*) FROM tblwordidx" initially took about 1 second to
> >> return a count of 2 million but after a few months it took several
> >> minutes of really hard HDD grinding.
> >
> > That's because there are dead entries in the index that weren't being
> > reused or cleaned up.  As I said, this has been fixed.
>
> That's doubtful: "select count(*) FROM foo" won't use an
> index. There are a bunch of other factors (e.g. dead heap tuples,
> changes in the pages cached in the buffer, disk fragmentation, etc.)
> that could effect performance in that situation, however.

*blush* Yeah, jumped the gun on that when I read that queries were
getting slower (churn of an index == slow creaping death for
performance).  A SELECT COUNT(*), however, wouldn't be affected by the
index growth problem.  Is the COUNT() on a view that uses an index?  I
haven't had any real problems with this kind of degredation outside of
indexes.  :-/  -sc

--
Sean Chittenden