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Date: Tue, 14 Jun 2005 16:27:55 -0700 (PDT)
From: Christoph Lameter <christoph@lameter.com>
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To: Andi Kleen <ak@suse.de>
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Subject: Re: [PATCH] Move some variables into the "most_readonly" section??
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On Wed, 15 Jun 2005, Andi Kleen wrote:

> > If these maps would start in the middle of a cacheline then additional 
> > cacheline fetches may become necessary to scan an array etc.
> 
> But the CPUs do prefetching anyways for that. Do you have numbers
> that this is actually worth it? 

Its not only for scanning an array. A struct may contains a lot of 
related information like for example boot_cpu_data. Aligning 
increases locality and the likelyhood that no additional cachelines have 
to be fetched.