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From: Mark Nelson <markn@au1.ibm.com>
To: Anton Blanchard <anton@samba.org>
Subject: Re: [PATCH] powerpc: pair loads and stores in copy_4k_page
Date: Thu, 11 Feb 2010 17:25:01 +1100
References: <20100211040754.GH3399@kryten>
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Hi Anton,

On Thursday 11 February 2010 15:07:54 Anton Blanchard wrote:
> 
> A number of our chips like loads and stores to be paired. A small kernel
> module testcase shows the improvement of pairing loads and stores in 
> copy_4k_page:
> 
> POWER6: +9%
> POWER7: +1.5%

I just tried this on one of our QS22 cell blades and it seems to cause
about half a percent speedup but that looks like it's within the noise
of the results that I'm getting.

In any case it doesn't look like it has a negative effect for cell.

Looks good!

Mark