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Date: Mon, 13 Aug 2012 09:27:53 -0700
From: Andi Kleen <ak@linux.intel.com>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Jan Beulich <JBeulich@suse.com>, Andy Lutomirski <luto@amacapital.net>,
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Subject: Re: [PATCH v2 4/6] x86: Add clear_page_nocache
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> Moving 64 bytes per cycle is faster on Sandy Bridge, but slower on
> Westmere. Any preference? ;)

You have to be careful with these benchmarks.

- You need to make sure the data is cache cold, cache hot is misleading.
- The numbers can change if you have multiple CPUs doing this in parallel.

-Andi