From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1GShkj-000425-EX for qemu-devel@nongnu.org; Wed, 27 Sep 2006 18:19:41 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1GShkj-00041t-2r for qemu-devel@nongnu.org; Wed, 27 Sep 2006 18:19:41 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1GShki-00041q-Tq for qemu-devel@nongnu.org; Wed, 27 Sep 2006 18:19:40 -0400 Received: from [65.74.133.4] (helo=mail.codesourcery.com) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA:32) (Exim 4.52) id 1GShpf-0007dz-N3 for qemu-devel@nongnu.org; Wed, 27 Sep 2006 18:24:47 -0400 From: Paul Brook Subject: Re: [Qemu-devel] RAM overcomittment Date: Wed, 27 Sep 2006 23:19:36 +0100 References: <1ACF2542-5DEE-49B5-8177-5B958911B0F6@gmail.com> <200609272242.00637.paul@codesourcery.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200609272319.37013.paul@codesourcery.com> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: The MoonSeeker Cc: qemu-devel@nongnu.org > Ok but some virtual solution like openVZ allow you run more VM than > the memory installed. By example, with openVZ I can create 10 Virtual > Machine who have a limite fixe to 200 MB but have guaranteed RAM of > 20MB. With qemu I need to have 10 X 200MB for VM's + 128 MB host of > RAM installed on the work station... Nonsense. > I think we can Save ressource because in the most case, the VM's will =A0 > never use the 200MB. I think it will be a nice if qemu implemented a =A0 > tool that let use exceed this limitation. Like I said, qemu is just like any other application. It's up to your host = OS=20 to handle management of physical RAM. There's no need for additional tools. > For my diploma project, I have to create a network simulator but with =A0 > these limitation I can't use qemu. Because if would like to simulate =A0 > 20 workstions I need 20 X 128 MB =3D 2560 MB of RAM... + host RAM!!! =A0 > But in the simulation, the VM's never will use all of ressource.. Just add a few Gb swap. Even the oldest of machines shouldn't have any prob= lem=20 adding say 4Gb swap. Depending on your OS settings you may not even need to= =20 do that. Besides which modern entry-level PCs should be able to take 2Gb ram without= =20 significant problems. Workstations with 8Gb aren't that hard to come by. Paul