From: Andi Kleen <ak@suse.de>
To: Paul Jackson <pj@sgi.com>
Subject: Re: [PATCH 01/02] cpuset memory spread slab cache filesys
Date: Tue, 28 Feb 2006 18:13:46 +0100
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Cc: Christoph Lameter <clameter@engr.sgi.com>, dgc@sgi.com, steiner@sgi.com,
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On Tuesday 28 February 2006 02:56, Paul Jackson wrote:
> Hmmm ... your thread with Andi confuses me ...
> 
> Oh well.
> 
> I take it that Andi is suggesting that there be the option to override
> the tasks mempolicy, in the particular case of these file i/o slab
> caches, with an interleave over the online nodes.

Yep exactly.
 
> This option would be useful in the case that a system is not using
> cpusets, but still wants to spread out these particular (sometimes
> large) file i/o caches.

Yep.
 
> Questions for Andi:
> 
>  1) Are you content to have such a interleave of these particular file
>     i/o slabs triggered by a mm/mempolicy.c option?  Or do you think
>     we need some sort of task external API to invoke this policy?

Task external. mempolicy.c has no good way to handle multiple policies
like this. I was thinking of a simple sysctl

I guess I can cook up a patch once your code is merged.


>  2) Do you recommend that the page (file buffer) cache also be
>     interleavable, across all online nodes, if optionally requested,
>     on systems not using cpusets?

Yes, but as a separate option.

-Andi

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