From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: KVM performance vs. Xen
Date: Thu, 30 Apr 2009 10:09:35 -0500
Message-ID: <49F9BF2F.3080700@codemonkey.ws>
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Cc: Andrew Theurer <habanero@linux.vnet.ibm.com>,
	kvm-devel <kvm@vger.kernel.org>
To: Avi Kivity <avi@redhat.com>
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Avi Kivity wrote:
> Anthony Liguori wrote:
>> Avi Kivity wrote:
>>>>
>>>> 1) I'm seeing about 2.3% in scheduler functions [that I recognize].
>>>> Does that seems a bit excessive?
>>>
>>> Yes, it is.  If there is a lot of I/O, this might be due to the 
>>> thread pool used for I/O.
>>
>> This is why I wrote the linux-aio patch.  It only reduced CPU 
>> consumption by about 2% although I'm not sure if that's absolute or 
>> relative.  Andrew?
>
> Was that before or after the entire path was made copyless?

Before so it's worth updating and trying again.

Regards,

Anthony Liguori