From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1LaYOO-0005x1-OM
	for qemu-devel@nongnu.org; Fri, 20 Feb 2009 11:38:24 -0500
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1LaYON-0005wm-Ce
	for qemu-devel@nongnu.org; Fri, 20 Feb 2009 11:38:24 -0500
Received: from [199.232.76.173] (port=59883 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1LaYON-0005wj-4W
	for qemu-devel@nongnu.org; Fri, 20 Feb 2009 11:38:23 -0500
Received: from mail2.shareable.org ([80.68.89.115]:53978)
	by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32)
	(Exim 4.60) (envelope-from <jamie@shareable.org>) id 1LaYOM-0004wB-Iv
	for qemu-devel@nongnu.org; Fri, 20 Feb 2009 11:38:22 -0500
Received: from jamie by mail2.shareable.org with local (Exim 4.63)
	(envelope-from <jamie@shareable.org>) id 1LaYOK-0002ep-Hw
	for qemu-devel@nongnu.org; Fri, 20 Feb 2009 16:38:20 +0000
Date: Fri, 20 Feb 2009 16:38:20 +0000
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] [RFC] More robust migration
Message-ID: <20090220163820.GC9726@shareable.org>
References: <499EBFD8.50307@amd.com> <499EC92E.9000401@codemonkey.ws>
	<200902201609.11547.paul@codesourcery.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <200902201609.11547.paul@codesourcery.com>
Reply-To: qemu-devel@nongnu.org
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: qemu-devel@nongnu.org

Paul Brook wrote:
> I suspect that in practice live migration of a VM between different qemu 
> versions ends up comparable to in-place live kernel upgrades. i.e. it takes 
> an awful lot of work and care to make it happen, and in practice isn't going 
> to happen for any particularly useful span of versions.

On the other hand, stored snapshots of guests which are ready to run
in a particular state are quite useful.  I'm under the impression the
migration code is/will be useful for storing snapshots of system (not
disk) state too.  Is that right?

-- Jamie