From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:53042) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QjuiQ-0002yT-9H for qemu-devel@nongnu.org; Thu, 21 Jul 2011 10:59:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qjubd-00075f-BH for qemu-devel@nongnu.org; Thu, 21 Jul 2011 10:52:09 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35183) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qjubd-00075Y-3t for qemu-devel@nongnu.org; Thu, 21 Jul 2011 10:52:05 -0400 Message-ID: <4E283D04.4040207@redhat.com> Date: Thu, 21 Jul 2011 08:51:48 -0600 From: Eric Blake MIME-Version: 1.0 References: <4E258635.2040108@redhat.com> <4E258D70.6000205@redhat.com> <4E25902D.2000403@redhat.com> <4E2593B0.1030508@redhat.com> <4E2594FB.4050203@redhat.com> <20110719164613.GE12026@redhat.com> <4E269070.8050101@redhat.com> <20110720093609.GA5015@redhat.com> <20110720101502.GC2560@nicolas-desktop> <20110720102845.GF5015@redhat.com> <4E27E610.7090502@redhat.com> <4E282DE6.1020603@redhat.com> <4E283554.4080903@redhat.com> In-Reply-To: <4E283554.4080903@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [libvirt] live snapshot wiki updated List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jes Sorensen Cc: "libvir-list@redhat.com" , QEMU Developers , Stefan Hajnoczi On 07/21/2011 08:19 AM, Jes Sorensen wrote: > There is a difference between upgrading to pick up additional features > and forced upgrade. > > It is not just a question of libvirt possibly reviewing a file format, > it is also having two codebases that needs to be implemented and maintained. Then give us a libblockid.so that provides a stable interface, and which is also used by qemu to manage QED, qcow3, ..., so that libvirt can rely on the stable library interface rather than having to learn new file formats all the time. But yes, we already had to upgrade libvirt code to parse qed formats, and anyone wanting to use qed via libvirt has to do a lockstep upgrade of both qemu and libvirt, because no one has yet written a nice shared library that can do it on our behalf through a stable API. -- Eric Blake eblake@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org