From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KNksR-0002NW-OD for qemu-devel@nongnu.org; Tue, 29 Jul 2008 04:48:15 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KNksR-0002MH-1d for qemu-devel@nongnu.org; Tue, 29 Jul 2008 04:48:15 -0400 Received: from [199.232.76.173] (port=45638 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KNksQ-0002M7-PO for qemu-devel@nongnu.org; Tue, 29 Jul 2008 04:48:14 -0400 Received: from mx1.redhat.com ([66.187.233.31]:35692) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1KNksQ-0006AX-IZ for qemu-devel@nongnu.org; Tue, 29 Jul 2008 04:48:14 -0400 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id m6T8mEWr030864 for ; Tue, 29 Jul 2008 04:48:14 -0400 Received: from file.fab.redhat.com (file.fab.redhat.com [10.33.63.6]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id m6T8mDU3027105 for ; Tue, 29 Jul 2008 04:48:13 -0400 Received: (from berrange@localhost) by file.fab.redhat.com (8.13.1/8.13.1/Submit) id m6T8mCId008886 for qemu-devel@nongnu.org; Tue, 29 Jul 2008 09:48:12 +0100 Date: Tue, 29 Jul 2008 09:48:12 +0100 From: "Daniel P. Berrange" Subject: Re: [Qemu-devel] [PATCH] qcow3 - arbitrary metadata Message-ID: <20080729084812.GO32498@redhat.com> References: <488E2752.7030008@codemonkey.ws> <20080729014939.GA27149@shareable.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080729014939.GA27149@shareable.org> Reply-To: "Daniel P. Berrange" , qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On Tue, Jul 29, 2008 at 02:49:40AM +0100, Jamie Lokier wrote: > Anthony Liguori wrote: > > Can you provide more information about what the metadata is used for and > > why it's so important for the metadata to be in the image verses in a > > separate file? > > Yeah, I have the opposite problem - too much in the same file :-) > > I want to be able to savevm, but some of my VMs don't have any qcow2 > images (because I don't trust them for mission-critical VMs since > recent discussion, or because they are floppy-only or CD-only VMs with > no hard disk). > > To enable savevm, at least according to docs, I have to have a qcow2 > image somewhere. So I add a redundant minimum-size unpartitioned > qcow2 hard disk and hope nobody minds... > > That seems a bit hackish. It would be nice if savevm could just write > to a named file and loadvm could read it. In libvirt we implement what I call 'unmanaged' save/restore to arbitrary files. We intend to add the QEMU style 'managed' save/restore to the disk image too. For the former we actually make use of the 'migrate' command - we just migrate to/from a local file :-) It works pretty nicely, so once Anthony gets KVM's migration support ported to plain QEMU i'd recommend using that technique - conceivably we could have a simple monitor command for making it easier to use in this scenario Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|