| 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 13:27:10 |
| Message-ID: | 20070830132710.GF5872@alvh.no-ip.org |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
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?
How about we use a constant estimate using the average tuple width code?
--
Alvaro Herrera http://www.amazon.com/gp/registry/CTMLCN8V17R4
"In fact, the basic problem with Perl 5's subroutines is that they're not
crufty enough, so the cruft leaks out into user-defined code instead, by
the Conservation of Cruft Principle." (Larry Wall, Apocalypse 6)
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