From: "Ralph Mason" <ralph.mason@telogis.com>
To: "'Mark Lewis'" <mark.lewis@mir3.com>
Cc: pgsql-performance@postgresql.org
References: <011b01c798d5$141365a0$3c3a30e0$@mason@telogis.com>
	<1179496683.31471.72.camel@archimedes>
In-Reply-To: <1179496683.31471.72.camel@archimedes>
Subject: Re: Ever Increasing IOWAIT
Date: Mon, 21 May 2007 08:41:41 +1200
Message-ID: <005c01c79b1f$459c2160$d0d46420$@mason@telogis.com>
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>You're not swapping are you?  One explanation could be that PG is
>configured to think it has access to a little more memory than the box
>can really provide, which forces it to swap once it's been running for
>long enough to fill up its shared buffers or after a certain number of
>concurrent connections are opened.
>
>-- Mark Lewis

No - no swap on this machine. The number of connections is stable.

Ralph


On Fri, 2007-05-18 at 10:45 +1200, Ralph Mason wrote:
> We have a database running on a 4 processor machine.  As time goes by
> the IO gets worse and worse peeking at about 200% as the machine loads
> up.
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> The weird thing is that if we restart postgres it=E2=80=99s fine for =
hours but
> over time it goes bad again.
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> (CPU usage graph here
> http://www.flickr.com/photos/8347741@N02/502596262/ )  You can clearly
> see where the restart happens in the IO area
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> This is Postgres  8.1.4 64bit.
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> Anyone have any ideas?
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> Thanks
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> Ralph
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> --
> Internal Virus Database is out-of-date.
> Checked by AVG Free Edition.
> Version: 7.5.432 / Virus Database: 268.15.9/573 - Release Date:
> 5/12/2006 4:07 p.m.
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--=20
Internal Virus Database is out-of-date.
Checked by AVG Free Edition.
Version: 7.5.432 / Virus Database: 268.15.9/573 - Release Date: =
5/12/2006 4:07 p.m.
=20

--=20
Internal Virus Database is out-of-date.
Checked by AVG Free Edition.
Version: 7.5.432 / Virus Database: 268.15.9/573 - Release Date: =
5/12/2006 4:07 p.m.
=20