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

To: Jan Beulich <JBeulich@xxxxxxxxxx>
Subject: [Xen-devel] Re: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology detection for AMD CPUs
From: Wei Huang <wei.huang2@xxxxxxx>
Date: Mon, 27 Jun 2011 12:26:05 -0500
Cc: George Dunlap <George.Dunlap@xxxxxxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>, Keir Fraser <keir@xxxxxxx>
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Thanks, Jan and George. I attach the latest version which fixes the indentation issues.


On 06/27/2011 03:58 AM, Jan Beulich wrote:
On 24.06.11 at 00:51, Wei Huang<wei.huang2@xxxxxxx>  wrote:

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.



Attachment: core_pair_1.txt
Description: core_pair_1.txt

Attachment: core_pair_2.txt
Description: core_pair_2.txt

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