From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Theurer <habanero@us.ibm.com>
Subject: Re: scaling problem with writable pagetables
Date: Thu, 16 Feb 2006 07:41:37 -0600
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	<6cc7be0ec36293dac6b8549c25e9d0be@cl.cam.ac.uk>
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To: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>
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Keir Fraser wrote:
>
> On 15 Feb 2006, at 18:49, Andrew Theurer wrote:
>
>> Below are per-function ratios of CPU time 
>> rev8830/rev8830-lock-reduction (derived from oprofile diffs)
>>
>> SDET:
>>
>> 9.84/1   restore_all_guest
>
> Kind of odd, since that function contains no locking. Perhaps VCPUs 
> are blocked so long that, by the time they get the CPU there is an 
> event pending and the hypercall gets preempted?
I was a bit surprised at that, too.
>
> What do the perfctr numbers look like for #hypercalls and #exceptions? 
> Also worth adding one to __hypercall_create_continuation as that'll 
> count #preemptions.
I have not taken perfctr numbers yet, but I will today.  Thanks,

-Andrew