From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] KVM simplified virtio balloon driver Date: Sat, 19 Jan 2008 09:05:52 +0200 Message-ID: <4791A150.3030402@qumranet.com> References: <20080114200357.GA18354@dmt> <200801171245.59510.rusty@rustcorp.com.au> <478EBA22.30301@codemonkey.ws> <200801171429.32888.rusty@rustcorp.com.au> <478ED32A.1060803@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm-devel , David Miller , virtualization-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Anthony Liguori Return-path: In-Reply-To: <478ED32A.1060803-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Anthony Liguori wrote: >> >> >>> It would be very useful too to write vb->num_pages into the config space >>> whenever it was updated. This way, the host can easily keep track of >>> where the guest is at in terms of ballooning. >>> >>> >> OTOH it's currently pretty obvious (and usually fatal) if the guest has >> trouble meeting the balloon requirements. A serious host needs a way of >> detecting stress in the guest anyway, which this doesn't offer until it's too >> late... >> >> > > The question I'm interested in answering though is not if but when. I > would like to know when the guest has reached it's target. > > Yes. We don't want to activate the RSS controller immediately; give the guest some time to adjust voluntarily. -- Any sufficiently difficult bug is indistinguishable from a feature. ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/