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Re: [Xen-devel] Xen spinlock questions

To: "Keir Fraser" <keir.fraser@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] Xen spinlock questions
From: "Jan Beulich" <jbeulich@xxxxxxxxxx>
Date: Fri, 15 Aug 2008 15:06:39 +0100
Cc: Jeremy Fitzhardinge <jeremy@xxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
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>>> Keir Fraser <keir.fraser@xxxxxxxxxxxxx> 15.08.08 15:01 >>>
>On 15/8/08 13:15, "Jan Beulich" <jbeulich@xxxxxxxxxx> wrote:
>> I can't really explain the results of testing with this version of the patch:
>> While the number of false wakeups got further reduced by somewhat
>> less than 20%, both time spent in the kernel and total execution time
>> went up (8% and 4% respectively) compared to my original (and from
>> all I can tell worse) version of the patch. Nothing else changed as far as
>> I'm aware.
>That is certainly odd. Presumably consistent across a few runs? I can't
>imagine where extra time would be being spent though...

Yes, I did at least five runs in each environment.


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