Hi, all! I have a server with 4 virtual machines ( using xen). Is there a way to make them share RAM? I found out something about balloons, but it didn't distribute RAM dynamically. So I decided that xen can't achieve that. I tried luci and ricci and now all my VMs are in a cluster. But I don't think this actually helped. Can you suggest a software and/or manual or a question which I should ask google for completing this task? All doms/nodes are with Centos 5.3(final). Thanks!
Larry wrote:> Hi, all! > I have a server with 4 virtual machines ( using xen). Is there a way to > make them share RAM? I found out something about balloons, but it didn'tNot with the current Xen I don't believe. I think some bleeding edge versions of KVM support memory sharing and/or ballooning. I'm a vmware user myself, which of course has had that technology stable for years now. nate
On Tue, 14 Apr 2009, Larry wrote:> Hi, all! > I have a server with 4 virtual machines ( using xen). Is there a way to > make them share RAM? I found out something about balloons, but it didn't > distribute RAM dynamically. So I decided that xen can't achieve that. > I tried luci and ricci and now all my VMs are in a cluster. But I don't > think this actually helped. > Can you suggest a software and/or manual or a question which I should > ask google for completing this task? >'over commit' of RAM is the phrase you are probably looking for. And this is one of the limitations of Xen (it doesn't). ---------------------------------------------------------------------- Jim Wildman, CISSP, RHCE jim at rossberry.com http://www.rossberry.com "Society in every state is a blessing, but Government, even in its best state, is a necessary evil; in its worst state, an intolerable one." Thomas Paine
Thank you, for all your answers! What about the other question? Can clustering help in completing this task? I thought cluster nodes are sharing RAM on default ( obviously I was wrong).>From your answers I'm getting to think that best decision for this task,in my case, is to buy some RAM. I'm not going to make more VMs. Their number will stay constant. nate, which vmware you use? VMware ESXi or VMWare Server or something else? Thanks, again for your help! p.s. Stable xen, has ballooning. You can say for every VM: memory=1024MB, max-mem=2048MB. And you can tweak the memory "manually", without having to restart the VM and without any other problems.
On Tue, Apr 14, 2009 at 3:05 PM, Larry <larry at itsbg.net> wrote:> Hi, all! > I have a server with 4 virtual machines ( using xen). Is there a way to > make them share RAM? I found out something about balloons, but it didn't > distribute RAM dynamically. So I decided that xen can't achieve that. > I tried luci and ricci and now all my VMs are in a cluster. But I don't > think this actually helped. > Can you suggest a software and/or manual or a question which I should > ask google for completing this task? > > All doms/nodes are with Centos 5.3(final). > > Thanks! > > > > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >AFAIK, openvz can do that. Of course, openvz has its own problems, but that's another matter.