From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1MWEfO-0006cE-5R
	for qemu-devel@nongnu.org; Wed, 29 Jul 2009 15:18:22 -0400
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1MWEfI-0006RR-Ts
	for qemu-devel@nongnu.org; Wed, 29 Jul 2009 15:18:21 -0400
Received: from [199.232.76.173] (port=45083 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1MWEfI-0006R7-DO
	for qemu-devel@nongnu.org; Wed, 29 Jul 2009 15:18:16 -0400
Received: from mail-ew0-f210.google.com ([209.85.219.210]:35622)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <filip.navara@gmail.com>) id 1MWEfH-0003fJ-Pv
	for qemu-devel@nongnu.org; Wed, 29 Jul 2009 15:18:16 -0400
Received: by ewy6 with SMTP id 6so217941ewy.34
	for <qemu-devel@nongnu.org>; Wed, 29 Jul 2009 12:18:14 -0700 (PDT)
MIME-Version: 1.0
In-Reply-To: <200907292011.38879.paul@codesourcery.com>
References: <20090729120719.GN30449@redhat.com>
	<20090729135057.GY30449@redhat.com>
	<5b31733c0907290735u5dd86d86i293f34df4ce09d10@mail.gmail.com>
	<200907292011.38879.paul@codesourcery.com>
Date: Wed, 29 Jul 2009 21:18:07 +0200
Message-ID: <5b31733c0907291218k624f97bbx62d8d6d49b8f0759@mail.gmail.com>
Subject: Re: [Qemu-devel] [PATCH v2] make windows notice media change
From: Filip Navara <filip.navara@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
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: Paul Brook <paul@codesourcery.com>
Cc: qemu-devel@nongnu.org, Gleb Natapov <gleb@redhat.com>

On Wed, Jul 29, 2009 at 9:11 PM, Paul Brook<paul@codesourcery.com> wrote:
>> Why shouldn't we support loading version 2 snapshots? Afterall that's
>> why we had the versioning in the first place.
>
> No it's not. Versioning was introduced to *prevent* loading old snapshots and
> crashing or ending up with inconsistent guest state. I'm still unconvinced
> that anything other than very short term backward compatibility is worthwhile
> or even viable.

I see it as a way to migrate a running guest to newer QEMU version, possibly
even with live migration. In fact I used it quite often back in the day when
snapshots were not part of qcow2 yet and when kqemu was still in its heydays.

Best regards,
Filip Navara