From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tracy R Reed Subject: Memory overcommit Date: Fri, 09 Dec 2005 14:00:10 -0800 Message-ID: <4399FE6A.9030000@copilotconsulting.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org I have been using Xen on a daily basis on a production (but not critical) machine for a number of months now. It's looking really good. One thing that I have not yet seen anyone mention as a feature that I would really like to see is the ability to overcommit memory. I have 2G of RAM in my machine. I would like to give a developer his own virtual domain to sandbox his application development without having to dedicate a whole piece of hardware to just him. But I know he won't really log in and use it all that often. If I give him 512M of my 2G that's 25% of my memory that will likely be unutilized most of the time. It would be great if I could assign more memory to domains than I actually have and just let it swap out idle pages. I bet there are a lot of boxes out there, especially in webserver colo's, that really don't get much traffic and really don't need as much RAM as they have in them for normal day to day operations. Just let them swap everything back in and use up to the maximum RAM configured for that domain if they get busy and need it but let it swap out the rest of the time so other busier domains can use the physical RAM. This is feature #1 on my Xen wishlist. Is there any work going into this area? -- Tracy R Reed http://copilotconsulting.com 1-877-MY-COPILOT