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Subject: Re: [PERFORM] Releasing memory during External sorting?
From: Simon Riggs <simon@2ndquadrant.com>
To: Ron Peacetree <rjpeace@earthlink.net>
Cc: pgsql-hackers@postgresql.org, pgsql-performance@postgresql.org
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Date: Sun, 25 Sep 2005 18:45:30 +0100
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On Fri, 2005-09-23 at 12:48 -0400, Ron Peacetree wrote:

> > I have some indications from private tests that very high memory settings
> >may actually hinder performance of the sorts, though I cannot explain that
> >and wonder whether it is the performance tests themselves that have issues.
> >
> Hmmm.  Are you talking about amounts so high that you are throwing the OS
> into paging and swapping thrash behavior?  If not, then the above is weird.

Thanks for your thoughts. I'll retest, on the assumption that there is a
benefit, but there's something wrong with my earlier tests.

Best Regards, Simon Riggs