From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: Proposed XENMEM_claim_pages hypercall: Analysis of problem and alternate solutions Date: Fri, 18 Jan 2013 16:45:42 -0500 Message-ID: <20130118214542.GB3047@phenom.dumpdata.com> References: <49049C00-89CA-4B43-9660-83B9ADC061E0@gridcentric.ca> <20121218221749.GA6332@phenom.dumpdata.com> <20130111160314.GD15353@phenom.dumpdata.com> <20130111190814.GD29020@phenom.dumpdata.com> <20130117151631.GF19975@ocelot.phlegethon.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20130117151631.GF19975@ocelot.phlegethon.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Tim Deegan Cc: Dan Magenheimer , "Keir (Xen.org)" , Ian Campbell , George Dunlap , Andres Lagar-Cavilla , Ian Jackson , xen-devel@lists.xen.org, Konrad Rzeszutek Wilk , Jan Beulich List-Id: xen-devel@lists.xenproject.org On Thu, Jan 17, 2013 at 03:16:31PM +0000, Tim Deegan wrote: > At 14:08 -0500 on 11 Jan (1357913294), Konrad Rzeszutek Wilk wrote: > > But the solution to the hypercall failing are multiple - one is to > > try to "squeeze" all the guests to make space > > AFAICT if the toolstack can squeeze guests up to make room then the > reservation hypercall isn't necessary -- just use the squeezing > mechanism to make sure that running VMs don't use up the memory you want > for building new ones. We might want to not do that until we have run out of options (this would be a toolstack option to select the right choice). The other option is to just launch the guest on another node. The reasoning for not wanting to squeeze the guests as it might cause the guest to fall in the OOM camp.