From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:59464)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <zhanghy@sangfor.com.cn>) id 1YFisE-0003uA-OF
	for qemu-devel@nongnu.org; Mon, 26 Jan 2015 07:34:35 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <zhanghy@sangfor.com.cn>) id 1YFis9-00033f-JN
	for qemu-devel@nongnu.org; Mon, 26 Jan 2015 07:34:34 -0500
Received: from smtp.sangfor.com.cn ([58.251.49.30]:46886
	helo=mail.sangfor.com.cn) by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <zhanghy@sangfor.com.cn>) id 1YFis9-000326-45
	for qemu-devel@nongnu.org; Mon, 26 Jan 2015 07:34:29 -0500
Date: Mon, 26 Jan 2015 20:25:06 +0800
From: "Zhang Haoyu" <zhanghy@sangfor.com.cn>
References: <201501211832330964659@sangfor.com.cn>,
	<54BF81F0.9070908@redhat.com>,
	<20150122232948.GQ12638@tesla.redhat.com>,
	<201501260907583380898@sangfor.com.cn>,
	<201501261913435951960@sangfor.com.cn>,
	<54C624E2.2010608@redhat.com>
Message-ID: <201501262024561264834@sangfor.com.cn>
Mime-Version: 1.0
Content-Type: text/plain;
	charset="gb2312"
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [question] incremental backup a running vm
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Paolo Bonzini <pbonzini@redhat.com>, Kashyap Chamarthy <kashyapc@fedoraproject.org>
Cc: Fam Zheng <famz@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>, qemu-devel <qemu-devel@nongnu.org>, kvm <kvm@vger.kernel.org>


On 2015-01-26 19:29:03, Paolo Bonzini wrote:
>
> On 26/01/2015 12:13, Zhang Haoyu wrote:
> > Thanks, Paolo,
> > but too many internal snapshots were saved by customers,
>> switching to external snapshot mechanism has significant impaction
> > on subsequent upgrade.
> 
> In that case, patches are welcome. :)
>
> > Another problem:
> > drive_backup just implement one time backup,
> > but I want VMWare's VDP-like backup mechanism.
> > The initial backup of a virtual machine takes comparatively more time,
>> because all of the data for that virtual machine is being backed up. 
> > Subsequent backups of the same virtual machine take less time, because
> > changed block tracking (log dirty) mechanism is used to only backup the dirty data.
> > After inittial backup done, even the VM shutdown, but subsequent backup also only 
>> copy the changed data.
> 
> As mentioned before, patches for this are on the list.
> 
I see, thanks, Paolo.
> Paolo