From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1IJfz6-0005E0-Pm for qemu-devel@nongnu.org; Fri, 10 Aug 2007 21:41:44 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1IJfz5-0005DZ-Uv for qemu-devel@nongnu.org; Fri, 10 Aug 2007 21:41:44 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1IJfz5-0005DW-SY for qemu-devel@nongnu.org; Fri, 10 Aug 2007 21:41:43 -0400 Received: from rv-out-0910.google.com ([209.85.198.187]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1IJfz5-0004VM-De for qemu-devel@nongnu.org; Fri, 10 Aug 2007 21:41:43 -0400 Received: by rv-out-0910.google.com with SMTP id k15so2907479rvb for ; Fri, 10 Aug 2007 18:41:42 -0700 (PDT) Message-ID: <59abf66e0708101841i76e26a35vcbc8df14b21f1ac0@mail.gmail.com> Date: Fri, 10 Aug 2007 22:41:41 -0300 From: "=?ISO-8859-1?Q?Jorge_Luc=E1ngeli_Obes?=" Subject: Re: [kvm-devel] [Qemu-devel] Re: Storing command line options in images In-Reply-To: <46BCC666.6050406@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <59abf66e0708092155t2e3cd5o32f23c018bed65af@mail.gmail.com> <46BC8C18.6020108@codemonkey.ws> <46BC9CDB.3080900@qumranet.com> <46BCB1DA.6060102@codemonkey.ws> <46BCBF73.5060406@qumranet.com> <46BCC666.6050406@codemonkey.ws> 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, Anthony Liguori Cc: kvm-devel@lists.sourceforge.net > > My feeling is that config files are outdated. When used with a gui, > > you end up writing silly parsers and stuff and still wrecking things > > horribly when the the gui writer's expectations don't match reality. > > When used without a gui, they increase the amount of details one has > > to remember (where's that config file? I renamed my image, did I > > remember to update the config file?). They also make upgrading more > > difficult. > > There's only so much that can be expressed on a command line. There are > actually limits to the command line size on a lot of platforms. I don't > see why reading options from a file is so much worse than reading them > from the command line. In my view, the bottom line is: we need an _easy_ way of launching VMs when one doesn't want all the options of the managed approach. I back Avi on this one, I would like to be able to do qemu guest.img without worrying about configuration files, or XML, or parsing. That's not to say that a global configuration file for QEMU wouldn't be useful, but I think it would solve a different problem. When I read Avi's TODO, I basically thought about getting rid of the long command lines I had to store in scripts. I wanted to write that command line once, and then forgetting about it, until I needed to change it. I wanted an image to be self-contained as much as possible. That's what I set to achieve. All that said, I rethought Anthony's idea of storing plain text in the image and with proper tools, it can work out. I don't like the idea of having users overwriting and padding files, but the approach seems less of a hack than using empty snapshots. In short: I think we will need to have something like 'qemu-img cmdline' anyways, independent of the implementation. That's because I would like an implementation that does not depend on extra files. For that, we already have libvirt and the likes. Cheers, Jorge