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Date: Sat, 17 Apr 2010 08:12:18 -0700
From: Arjan van de Ven <arjan@infradead.org>
Subject: Re: hugepages will matter more in the future
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To: Avi Kivity <avi@redhat.com>
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On Mon, 12 Apr 2010 14:29:58 +0300
Avi Kivity <avi@redhat.com> wrote:
> Pointer chasing defeats OoO.  The cpu is limited in the amount of 
> speculation it can do.

Pointer chasing defeats the CPU cache as well.
As long as the CPU cache contains, mostly, the page tables for all the
data in the cache, applications that try to work good with a cache
don't notice too much. Sure, once you start doing pointer chasing cache
misses things suck. they do very much so.


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org

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