From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: qcow2 slowdown in kvm-78,79
Date: Wed, 19 Nov 2008 16:06:46 -0600
Message-ID: <49248DF6.60201@codemonkey.ws>
References: <1227019192.22098.4.camel@henrik-desktop>	<20081119182317.GA31893@us.ibm.com> <49245A61.9050504@codemonkey.ws> <gg1qk4$bap$1@ger.gmane.org>
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Cc: kvm@vger.kernel.org
To: Thomas Mueller <thomas@chaschperli.ch>
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Thomas Mueller wrote:
> On Wed, 19 Nov 2008 12:26:41 -0600, Anthony Liguori wrote:
>   
>>
>> This is probably the change to cache=writethrough.  I bet if you set
>> cache=writeback then you'll see this go away.
>>     
>
> this was it. cache=writeback and the throughput goes from 10mb/s to 80/mb/
> s with if=scsi
>   

Yeah, we'll most likely switch back to cache=writeback for the default 
for qcow2 images.  qcow2 needs some lovin'.

Regards,

Anthony Liguori

> thanks.
>
> - Thomas
>
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