Re: One source of constant annoyance identified

From: Curt Sampson <cjs(at)cynic(dot)net>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Markus Wollny <Markus(dot)Wollny(at)computec(dot)de>, <pgsql-general(at)postgresql(dot)org>
Subject: Re: One source of constant annoyance identified
Date: 2002-06-28 09:55:57
Message-ID: Pine.NEB.4.43.0206281854100.6613-100000@angelic.cynic.net
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On Thu, 27 Jun 2002, Tom Lane wrote:

> So you haven't really solved the problem --- somewhere there is a query
> being issued that ramps the backend up to a lot of memory. All you've
> done is ensured that the backend won't hang around very long. The
> persistent connection isn't really at fault, except in that it causes
> backends to keep being used after their memory usage has become bloated.

Yeah, but if the queries after that are not using all of the mapped
memory, that should be swapped out fairly quickly because the
machine is short on memory.

Same for memory leaks; if you're losing a lot of memory, you'd
think there would be a fair number of pages you never touch that
could then be swapped out.

The bloated processes, at least from the top fragment I saw, appear
to have a working set of 200-250 MB; basically the entire data
space is resident. So what's touching all of those pages often
enough that they don't get swapped?

cjs
--
Curt Sampson <cjs(at)cynic(dot)net> +81 90 7737 2974 http://www.netbsd.org
Don't you know, in this new Dark Age, we're all light. --XTC

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