Re: postgresql meltdown on PlanetMath.org - Mailing list pgsql-performance

From Sean Chittenden
Subject Re: postgresql meltdown on PlanetMath.org
Date
Msg-id 20030317061011.GH23355@perrin.int.nxad.com
Whole thread Raw
In response to Re: postgresql meltdown on PlanetMath.org  (Logan Bowers <logan@datacurrent.com>)
Responses Re: postgresql meltdown on PlanetMath.org
List pgsql-performance
> I don't know what your definition of "high" is, but I do find that
> turnover can degrade performance over time.  Perhaps one of the devs
> can enlighten me, but I have a database that turns over ~100,000
> rows/day that does appear to slowly get worse.  The updates are done
> in batches and I "VACUUM" and "VACUUM ANALYZE" after each batch
> (three/day) but I found that over time simple queries would start to
> hit the disk more and more.

Creeping index syndrome.  Tom recently fixed this in HEAD.  Try the
latest copy from the repo and see if this solves your problems.

> 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.

-sc


PS  It's good to see you around again.  :)

--
Sean Chittenden

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