From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KXaM5-0001y4-AL for qemu-devel@nongnu.org; Mon, 25 Aug 2008 07:35:29 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KXaM2-0001xH-3Z for qemu-devel@nongnu.org; Mon, 25 Aug 2008 07:35:27 -0400 Received: from [199.232.76.173] (port=42339 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KXaM1-0001xA-PC for qemu-devel@nongnu.org; Mon, 25 Aug 2008 07:35:25 -0400 Received: from mail2.shareable.org ([80.68.89.115]:58248) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KXaM1-0001Tp-BD for qemu-devel@nongnu.org; Mon, 25 Aug 2008 07:35:25 -0400 Date: Mon, 25 Aug 2008 12:35:22 +0100 From: Jamie Lokier Subject: Re: [Qemu-devel] [PATCH v2 4/6] Use libuuid if available. Message-ID: <20080825113522.GA20960@shareable.org> References: <20080825095800.18703.30602.stgit@gleb-debian.qumranet.com.qumranet.com> <20080825095820.18703.69963.stgit@gleb-debian.qumranet.com.qumranet.com> <20080825112621.GL6192@minantech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080825112621.GL6192@minantech.com> Reply-To: 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 Cc: Andreas =?iso-8859-1?Q?F=E4rber?= Gleb Natapov wrote: > > I don't remember hearing an answer on why this is necessary. For which > > use case can't you just either use -uuid `uuidgen` or a hardcoded > > default value like the Slirp IPv4 subnet? > It can be used for UUID generation when VM is started for the first time. > Management application can retrieve UUID using monitor and use it for > consequent runs. But the same result can be achieved in a different way > too. So no, I really don't have a strong use case for this feature, but > the patch set is organised in such way that it is possible to ignore > this particular patch. Yeah, but Management Application is often not used. QEMU's philosophy seems to be that it should be quite usable from the command line, and leaving _off_ options should give sane defaults. My immediate thought is that UUID would make sense at disk image generation time - i.e. stored in qcow2 when qemu-img runs - until such time as QEMU has a useful config/state file format. Then it should go in that file, just like all other VM systems. -- Jamie