From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Problem with SMP boot Date: Sat, 27 Jan 2007 10:27:15 +0200 Message-ID: <45BB0CE3.4010005@qumranet.com> References: <1169765044.30807.19.camel@localhost.localdomain> <45BA413F.5030307@qumranet.com> <45BA5032.6050100@castleinthesky.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Matthew Hall Return-path: In-Reply-To: <45BA5032.6050100-Etm38r6YSMlqcVXhcSD7Ah2eb7JE58TQ@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 Matthew Hall wrote: > Avi Kivity wrote: > >> kvm only supports uniprocessor guests at this time. >> > > Out of interest, if/when when. > kvm supports smp guests aswell as hosts would > the guest be presented with a multiple virtual or physical cpu's? > Ie. If the guest has multiple virtual cpu's the process would only run > as a single task which would then affine to a single cpu on a multiple > cpu host. > > So could kvm let an smp guest share the physical cpu's the host has? > kvm maps a guest vcpu to a host thread. In turn, the host scheduler maps host threads to host cpus, so the mapping of vcpus to cpus depends on resource availability: if you have enough cpus, the scheduler will assign each vcpu to a separate cpu. The user will also be able to affect the mapping by binding vcpu threads to specific processors. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV