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Subject: Re: [BUG] 2.4 VM sucks. Again
To: Martin.Bligh@us.ibm.com (Martin J. Bligh)
Date: Fri, 24 May 2002 17:14:54 +0100 (BST)
Cc: alan@lxorguk.ukuu.org.uk (Alan Cox),
        roy@karlsbakk.net (Roy Sigurd Karlsbakk), linux-kernel@vger.kernel.org
In-Reply-To: <421830000.1022255618@flay> from "Martin J. Bligh" at May 24, 2002 08:53:38 AM
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> > What sort of setup. I can't duplicate the problem here ?
> 
> I'm not sure exactly what Roy was doing, but we were taking a machine
> with 16Gb of RAM, and reading files into the page cache - I think we built up
> 8 million buffer_heads according to slabinfo ... on a P4 they're 128 bytes each,
> on a P3 96 bytes.

The buffer heads one would make sense. I only test on realistic sized systems. 
Once you pass 4Gb there are so many problems its not worth using x86 in the
long run