From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: automatic memory ballooning? Date: Mon, 17 Aug 2009 14:35:12 +0300 Message-ID: <4A894070.9080402@redhat.com> References: <200908160355.46652.tfjellstrom@shaw.ca> <200908160818.46436.tfjellstrom@shaw.ca> <4A88209B.3090908@redhat.com> <200908170449.40945.tfjellstrom@shaw.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, dlaor@redhat.com To: tfjellstrom@shaw.ca Return-path: Received: from mx2.redhat.com ([66.187.237.31]:35684 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757762AbZHQLfO (ORCPT ); Mon, 17 Aug 2009 07:35:14 -0400 In-Reply-To: <200908170449.40945.tfjellstrom@shaw.ca> Sender: kvm-owner@vger.kernel.org List-ID: On 08/17/2009 01:49 PM, Thomas Fjellstrom wrote: > One thing I found odd about kvm's ballooning is that it actually seems to > change how much ram the guest has. I really didn't expect "free -m" to report > that the guest only had 64M ram after I manually ballooned the ram. I was > however expecting it just to free ram it wasn't using in the host. To me, it > just doesn't seem to be the same thing. now it'll start swapping at 64M ram > instead of just reallocating the ram it used to have. > You expectations aren't realistic. kvm never allocates the ram the guest doesn't use in the first place. Ballooning just the "free" memory is pointless since it's usually a very small amount. It may be worthwhile for the guest to give up that memory voluntarily though. -- error compiling committee.c: too many arguments to function