Date: Mon, 6 Feb 2006 10:21:51 -0800 (PST)
From: Christoph Lameter <clameter@engr.sgi.com>
To: Andi Kleen <ak@suse.de>
cc: Paul Jackson <pj@sgi.com>, mingo@elte.hu, akpm@osdl.org, dgc@sgi.com,
       steiner@sgi.com, Simon.Derr@bull.net, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/5] cpuset memory spread basic implementation
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 <20060206063549.d155c619.pj@sgi.com> <Pine.LNX.4.62.0602060839440.16337@schroedinger.engr.sgi.com>
 <200602061811.49113.ak@suse.de>
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On Mon, 6 Feb 2006, Andi Kleen wrote:

> I still don't quite agree. As long as the latency penalty of going
> off node is not too bad (let's say < factor 2) i think it's better
> to spread out the caches than to always locate them locally.

AFAIK you can reach these low latency factors only if multiple nodes are 
on the same motherboard. Likely Opteron specific?

> If you have a much worse worst case NUMA factor it might be different,
> but even there it would be a good idea to at least spread it out
> to nearby nodes.

I dont understand you here. What would be the benefit of selecting more 
distant memory over local? I can only imagine that this would be 
beneficial if we know that the data would be used later by other 
processes.
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