Re: [PATCH RFC 1/2] kvm: Handle undercommitted guest case in PLEhandler

[Avi Kivity]

On 10/04/2012 03:07 PM, Peter Zijlstra wrote:
> On Thu, 2012-10-04 at 14:41 +0200, Avi Kivity wrote:
>> 
>> Again the numbers are ridiculously high for arch_local_irq_restore.
>> Maybe there's a bad perf/kvm interaction when we're injecting an
>> interrupt, I can't believe we're spending 84% of the time running the
>> popf instruction. 
> 
> Smells like a software fallback that doesn't do NMI, hrtimer based
> sampling typically hits popf where we re-enable interrupts.

Good nose, that's probably it.  Raghavendra, can you ensure that the PMU
is properly exposed?  'dmesg' in the guest will tell.  If it isn't, -cpu
host will expose it (and a good idea anyway to get best performance).

-- 
error compiling committee.c: too many arguments to function
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