From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:47115) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S2RO7-0000mo-9y for qemu-devel@nongnu.org; Tue, 28 Feb 2012 13:03:00 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1S2RO5-0004El-Ei for qemu-devel@nongnu.org; Tue, 28 Feb 2012 13:02:58 -0500 Received: from plane.gmane.org ([80.91.229.3]:48766) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S2RO5-0004EX-7f for qemu-devel@nongnu.org; Tue, 28 Feb 2012 13:02:57 -0500 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1S2RO3-0004Zo-Fd for qemu-devel@nongnu.org; Tue, 28 Feb 2012 19:02:55 +0100 Received: from 93-34-182-16.ip50.fastwebnet.it ([93.34.182.16]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 28 Feb 2012 19:02:55 +0100 Received: from pbonzini by 93-34-182-16.ip50.fastwebnet.it with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 28 Feb 2012 19:02:55 +0100 From: Paolo Bonzini Date: Tue, 28 Feb 2012 19:02:40 +0100 Message-ID: References: <4F4D10B9.7020203@redhat.com> <453ad5e3-36eb-45bb-8ce0-91ed7611b5fc@zmail16.collab.prod.int.phx2.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit In-Reply-To: <453ad5e3-36eb-45bb-8ce0-91ed7611b5fc@zmail16.collab.prod.int.phx2.redhat.com> Subject: Re: [Qemu-devel] Live Block Migration using Mirroring List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Il 28/02/2012 18:46, Federico Simoncelli ha scritto: > > > Thank you for getting this. Being able to have a bogus backing file > > > was a bonus but it's not really required for the mirrored live block > > > migration. We can add the support for switching the backing file in the > > > drive-reopen part. > > > > Wait, it's not really required for oVirt because it creates the > > snapshot outside QEMU. What about everyone else? > > They'll have (as oVirt) two mirrored snapshot pointing at the same > base. The only difference is that the image is created internally, but > that's not hard. Can you detail how you are switching the backing file in the drive-reopen? Either the BlockDriverState opened by blkmirror, or the one opened at the end, will have to use the "wrong" backing_file. How do you arrange for that? Paolo