From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=53967 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OGfWx-0003Kz-MN for qemu-devel@nongnu.org; Mon, 24 May 2010 17:49:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OGfWs-0004t3-NQ for qemu-devel@nongnu.org; Mon, 24 May 2010 17:49:51 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.145]:50560) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OGfWs-0004sw-Ij for qemu-devel@nongnu.org; Mon, 24 May 2010 17:49:46 -0400 Received: from d01relay07.pok.ibm.com (d01relay07.pok.ibm.com [9.56.227.147]) by e5.ny.us.ibm.com (8.14.3/8.13.1) with ESMTP id o4OLXRJR010141 for ; Mon, 24 May 2010 17:33:27 -0400 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay07.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o4OLnjfk1138794 for ; Mon, 24 May 2010 17:49:45 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o4OLnik9025359 for ; Mon, 24 May 2010 18:49:44 -0300 Message-ID: <4BFAF477.4030303@linux.vnet.ibm.com> Date: Mon, 24 May 2010 16:49:43 -0500 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] Re: [PATCH v2 12/15] monitor: Add basic device state visualization References: <1f557b9feb1965a61e64f7166bcf4918bed8d0ec.1274516288.git.jan.kiszka@web.de> <4BF82895.6000706@redhat.com> <4BFAE004.6090501@codemonkey.ws> <4BFAE302.40806@web.de> In-Reply-To: <4BFAE302.40806@web.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Juan Quintela , Jan Kiszka , qemu-devel@nongnu.org, Luiz Capitulino , Avi Kivity , Markus Armbruster On 05/24/2010 03:35 PM, Jan Kiszka wrote: > In contrast to save/loadvm, device_show does not provide a > backward-compatible output. Not only field names can change (as a result > of internal refactoring), Field names could change, but that seems unlikely and unnecessary. > fields may even disappear, That would break live migration. The output of device_show when specifying -M pc-0.13 should always be the same. If it's not, I believe that's a bug. The output of device_show across multiple qemu versions without specifying a -M could certainly be different but that's to be expected since you have a different hardware model. > new ones may pop > up. vmstate makes this transparent for reading of old states, but not > for visualization. > > That said, I see no use case yet that would justify the effort for > making state dumps as stable as vmstates. > They already are. It's just a matter of whether we declare it as such AFAICT. Regards, Anthony Liguori > Jan >