From: Avi Kivity <avi@redhat.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Chris Mason <chris.mason@oracle.com>,
Diego Calleja <diegocg@gmail.com>,
linux-btrfs@vger.kernel.org
Subject: Re: Poor performance with qemu
Date: Thu, 08 Apr 2010 18:36:15 +0300 [thread overview]
Message-ID: <4BBDF7EF.4010100@redhat.com> (raw)
In-Reply-To: <20100408153456.GA26113@infradead.org>
On 04/08/2010 06:34 PM, Christoph Hellwig wrote:
> On Thu, Apr 08, 2010 at 06:28:54PM +0300, Avi Kivity wrote:
>
>> When it updates qcow2 metadata or when the guest issues a barrier. It's
>> relatively new. I have a patch that introduces cache=volatile somewhere.
>>
> qcow2 does not issues any fsyncs by itself, it only passes throught the
> guests ones. The only other placess issueing fsyncs is commit a COW
> image back to the base image, and on migreation.
>
Shouldn't it do that then? What's the point of fsyncing guest data if
qcow2 metadata is volatile?
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2010-04-08 15:36 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-28 15:18 Poor performance with qemu Diego Calleja
2010-03-30 12:56 ` Chris Mason
2010-04-08 14:58 ` Avi Kivity
2010-04-08 15:21 ` Gordan Bobic
2010-04-08 15:26 ` Chris Mason
2010-04-08 15:28 ` Avi Kivity
2010-04-08 15:32 ` Chris Mason
2010-04-08 15:34 ` Christoph Hellwig
2010-04-08 15:36 ` Avi Kivity [this message]
2010-04-08 15:39 ` Christoph Hellwig
2010-04-08 15:32 ` Christoph Hellwig
-- strict thread matches above, loose matches on Subject: below --
2010-03-29 19:21 Markus Suvanto
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