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[Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology de

To: "Wei Huang" <wei.huang2@xxxxxxx>
Subject: [Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
From: "Jan Beulich" <JBeulich@xxxxxxxxxx>
Date: Mon, 27 Jun 2011 09:58:26 +0100
Cc: George Dunlap <George.Dunlap@xxxxxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Keir Fraser <keir@xxxxxxx>
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>>> On 24.06.11 at 00:51, Wei Huang <wei.huang2@xxxxxxx> wrote:
> Hi,
> The following two patches enable core-pair topology detection for AMD 
> CPUs. The main idea is to record compute unit information into 
> cpuinfo_x86 and use it when building sibling map. The sibling map will 
> be used by Xen credit scheduler to coordinate VCPU scheduling in a 
> fashion similar to SMT. This code is very similar to upstream Linux kernel.
> Regarding the performance improvement, I saw ~8% improvement running 
> kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay 
> benchmark using this patch and he saw ~5% improvement. No perf 
> degradation was seen so far.
> Please review.

Apart from some indentation issues these look fine to me.


> Thanks,
> -Wei

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