On Wed, 2007-08-15 at 15:52 +0200, Farkas Levente wrote: > Gregory Haskins wrote: > > > > On thing that is interesting about this (to me) is that, in a way it > > kind of is a "poor mans" swap for the guests memory on the host. E.g. > > you could give your guests a really small amount of "physical" ram (say, > > I dunno, 64MB/ea) and a large swap file (say several gigs). Since the > > disk-io emanating from the guest would likely be mediated by the hosts > > buffercache, its kind of like you just gave the guest a large chunk of > > (indirectly accessible) pageable ram. > > i just imagine th opposite setup. suppose i've got 4 guest and 4gb ram. > most of the time guest are idle they just used as a compile server for > different platforms (centos, mandrake, fedora, windows etc). i can > schedule the compiles (ie. 1:00 guest1, 2:00 guest 2 etc). in this case > i gives the host 1-2gb and all guest 2-3gb logical ram. which is in sum > 9-14gb ram even i have only 4gb physical ram. > _BUT_ as i know that the guests are usually idle _and_ they have high > resource requirement at different time, probably all of them can use > 2-3gb real ram as memory. and in this setup if all other time most of > the guest's ram are swapped out it's not really bother me since they are > idle. > or did is something misunderstood?
I think you are just misunderstanding me. We are saying the same thing (I think) :) What it sounds like you are talking about is oversubscribing your ram. IIUC this is not possible today unless you employ a guest-swap scheme like I mentioned. Until the balloon/swap support is in, the guest "ram" allocation aggregated across all VMs cannot exceed host-physical ram (in your case, 4GB). In fact, it has to be a little less of course so the host still has some to play with ;) ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ kvm-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/kvm-devel
