Re: Ever Increasing IOWAIT

From: Mark Lewis <mark(dot)lewis(at)mir3(dot)com>
To: Ralph Mason <ralph(dot)mason(at)telogis(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: Ever Increasing IOWAIT
Date: 2007-05-18 13:58:03
Message-ID: 1179496683.31471.72.camel@archimedes
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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

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.
>
>
>
> The weird thing is that if we restart postgres it’s fine for hours but
> over time it goes bad again.
>
>
>
> (CPU usage graph here
> http://www.flickr.com/photos/8347741(at)N02/502596262/ ) You can clearly
> see where the restart happens in the IO area
>
>
>
> This is Postgres 8.1.4 64bit.
>
>
>
> Anyone have any ideas?
>
>
>
> Thanks
>
> Ralph
>
>
>
>
>
> --
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