From mboxrd@z Thu Jan  1 00:00:00 1970
From: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Subject: Re: [PATCH 1/2] ARM: KVM: Yield CPU when vcpu executes a WFE
Date: Tue, 08 Oct 2013 20:32:59 +0530
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Cc: Raghavendra KT <raghavendra.kt.linux@gmail.com>,
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To: Marc Zyngier <marc.zyngier@arm.com>
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[...]
>>> +               kvm_vcpu_on_spin(vcpu);
>>
>> Could you also enable CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT for arm and
>> check if ple handler logic helps further?
>> we would ideally get one more optimization folded into ple handler if
>> you enable that.
>
> Just gave it a go, and the results are slightly (but consistently)
> worse. Over 10 runs:
>
> Without RELAX_INTERCEPT: Average run 3.3623s
> With RELAX_INTERCEPT: Average run 3.4226s
>
> Not massive, but still noticeable. Any clue?

Is it  a 4x overcommit? Probably we would have hit the code
overhead if it were small guests.

RELAX_INTERCEPT is worth enabling for large guests with
overcommits.