From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1ChGRd-00059e-2N for qemu-devel@nongnu.org; Wed, 22 Dec 2004 19:03:05 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1ChGRa-00058L-BG for qemu-devel@nongnu.org; Wed, 22 Dec 2004 19:03:03 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1ChGRY-00056j-Hh for qemu-devel@nongnu.org; Wed, 22 Dec 2004 19:03:00 -0500 Received: from [24.206.159.247] (helo=shawus.com) by monty-python.gnu.org with smtp (Exim 4.34) id 1ChGFm-0002nI-Jc for qemu-devel@nongnu.org; Wed, 22 Dec 2004 18:50:52 -0500 Message-ID: <001201c4e881$0e9a1260$964aa50c@computername> From: "jeebs" References: <41C9A386.8050200@hermes.cam.ac.uk><003201c4e865$3fd98f20$964aa50c@computername> <41C9FEB8.1050803@hermes.cam.ac.uk> Subject: Re: [Qemu-devel] What is the minimal linux setup for running Qemu ? Date: Wed, 22 Dec 2004 17:50:40 -0600 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable 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 From: "Richard Neill" > Actually, the metropipe key doesn't have this problem. The Guest OS is = > Damnn Small Linux, which is knoppix-based. This is simply an iso = CD-ROM=20 > (image) which is read-only. So the only writes are to your=20 Right. > home-directory. I haven't tested it, but I'd assume that the memory = key=20 > home directory is mounted sync,noatime. I don't happen to have a memory stick to test it with. (To be honest, = I've never gotten around to buying one.) =20 > Metropipe's product is actually quite interesting, since they aim to=20 > store all your files on their server, and the memory key provides=20 > firefox,ssh etc and a virtual private network. There's nothing on the web site about that. Their VPM page talks about storing things 'in your pocket' etc., so it = sounds like just a typical local virtual drive right on the memory = device itself. That's what prompted to me make my comment in here. They do provide a demo of their tunneler, but I don't see anything about = the product requiring its use etc. etc. =20 >> Any virtual disk is going to do quite a few writes, and flash memory = can only do so many before it starts to fail. >=20 > I thought this number was > 100,000 - so it's still not really an=20 > issue except for atime and swap. I really don't know what the cycle count is. Certainly on the higher quality flash chips, it's over a million bit = write cycles. But with so many ultra cheap memory sticks with memory from no telling = where, it's not something I'd want to depend on for more than a few tens = of thousand writes per bit. And unless there is proof to the contrary about the OS and the apps, you = kind of have to assume that anytime you actually run any programs, it's = going to update a directory or a config file, or whatever. Maybe I'm wrong, but at this point, I find it hard to believe that it's = not going to be doing lots of writes to the virtual disk when you = actually use stuff, like MetroPipe is trying to suggest. Simply = booting it for a demonstration or the ocasional emergency, etc. is no = problem. But MetroPipe is talking about actually using it for real, and I'm real = hesitant about the life span of the flash area where the directories are = at. Unless MetroPipe has taken explicit steps to reduce this and I = don't know about it. There isn't enough information of the web site to say for sure how it's = set up (I haven't tried it yet), but I'd guess it's nothing more than a = typical virtual disk for storage of your stuff, and an ISO for the = linux. Just a simple, no frills setup involving qemu, an empty virtual disk, = and a standard DSL iso image. That's why I said it was interesting, but = not inovative. (If I'm wrong, then great!) > Not relevant here, but doesn't JFFS deal with this problem? Don't know. =20