From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [v6] kvm/fpu: Enable fully eager restore kvm FPU
Date: Thu, 23 Apr 2015 13:28:09 -0700
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References: <1429823583-3226-1-git-send-email-liang.z.li@intel.com> <55390F9A.2070808@intel.com>
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	Xudong Hao <xudong.hao@intel.com>
To: Dave Hansen <dave.hansen@intel.com>,
	Liang Li <liang.z.li@intel.com>, kvm@vger.kernel.org,
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On 04/23/2015 08:28 AM, Dave Hansen wrote:
> On 04/23/2015 02:13 PM, Liang Li wrote:
>> When compiling kernel on westmere, the performance of eager FPU
>> is about 0.4% faster than lazy FPU.
> 
> Do you have an theory why this is?  What does the regression come from?
> 

This is interesting since previous measurements on KVM have had the
exact opposite results.  I think we need to understand this a lot more.

	-hpa