From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: qemu and qemu.git -> Migration + disk stress
 introduces qcow2 corruptions
Date: Wed, 9 Nov 2011 22:18:37 +0200
Message-ID: <20111109201836.GA28457@redhat.com>
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	<4EBAB236.2060409@redhat.com> <4EBAB9FA.3070601@codemonkey.ws>
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Cc: Lucas Meneghel Rodrigues <lmr@redhat.com>, Kevin Wolf <kwolf@redhat.com>,
	KVM mailing list <kvm@vger.kernel.org>,
	Juan Jose Quintela Carreira <quintela@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	QEMU devel <qemu-devel@nongnu.org>, Avi Kivity <avi@redhat.com>
To: Anthony Liguori <anthony@codemonkey.ws>
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On Wed, Nov 09, 2011 at 11:35:54AM -0600, Anthony Liguori wrote:
> On 11/09/2011 11:02 AM, Avi Kivity wrote:
> >On 11/09/2011 06:39 PM, Anthony Liguori wrote:
> >>
> >>Migration with qcow2 is not a supported feature for 1.0.  Migration is
> >>only supported with raw images using coherent shared storage[1].
> >>
> >>[1] NFS is only coherent with close-to-open which right now is not
> >>good enough for migration.
> >
> >Say what?
> 
> Due to block format probing, we read at least the first sector of
> the disk during start up.

A simple solution is not to do any probing before the VM is first
started on the incoming path.

Any issues with this?

-- 
MST