Re: Out of Memory - 8.2.4

From: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Marko Kreen <markokr(at)gmail(dot)com>, Jeff Amiel <becauseimjeff(at)yahoo(dot)com>, pgsql-general(at)postgresql(dot)org
Subject: Re: Out of Memory - 8.2.4
Date: 2007-08-30 17:23:48
Message-ID: 20070830172348.GU5872@alvh.no-ip.org
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Tom Lane escribió:
> Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> > I'm not having much luck really. I think the problem is that ANALYZE
> > stores reltuples as the number of live tuples, so if you delete a big
> > portion of a big table, then ANALYZE and then VACUUM, there's a huge
> > misestimation and extra index cleanup passes happen, which is a bad
> > thing.
>
> Yeah ... so just go with a constant estimate of say 200 deletable tuples
> per page?

This seems the most reasonable approach for now. So this is the patch.

--
Alvaro Herrera http://www.PlanetPostgreSQL.org/
"I call it GNU/Linux. Except the GNU/ is silent." (Ben Reiter)

Attachment Content-Type Size
maintworkmem-estimate-2.patch text/x-diff 2.9 KB

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