From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Subject: Re: [PATCH 11/11] KVM: MMU: improve write flooding detected
Date: Fri, 26 Aug 2011 22:24:27 +0800
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Cc: Avi Kivity <avi@redhat.com>, LKML <linux-kernel@vger.kernel.org>,
	KVM <kvm@vger.kernel.org>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 08/26/2011 06:53 PM, Marcelo Tosatti wrote:
> On Fri, Aug 26, 2011 at 11:18:01AM +0800, Xiao Guangrong wrote:
>> On 08/25/2011 09:47 PM, Marcelo Tosatti wrote:
>>
>>> I guess it is OK to be more trigger happy with zapping by ignoring
>>> the accessed bit, clearing the flood counter on page fault.
>>>
>>
>> Yeah, i like this way, is this patch good for you?
> 
> Looks fine, can you rerun kernbench?
> 

Sure, i tested the performance of this way, there is the result:

The origin way:
2m56.561
2m50.651
2m51.220
2m52.199
2m48.066

The way of using accessed bit:
2m51.194
2m55.980
2m50.755
2m47.396
2m46.807

The way of ignoring accessed bit:
2m45.547
2m44.551
2m55.840
2m56.333
2m45.534

I think the result is not bad.