From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Novotny Subject: [PATCH] Add maxvcpus support Date: Wed, 25 Nov 2009 12:14:02 +0100 Message-ID: <4B0D117A.2070808@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: "'xen-devel@lists.xensource.com'" List-Id: xen-devel@lists.xenproject.org Hi, this is patch to add maxvcpus support to xen xm command. It's using vcpu_avail bitmask and sets the number of vcpus to maxvcpus if present. If it's not present, old behavior is preserved. In domain config file you can define it as follows: maxvcpus = 4 vcpus = 2 this automatically sets vcpus to 4 and corresponding bitmask to present 2 vcpus in the guest with option to increase it up to 4 vcpus. If maxvcpus is not present, the old behavior for vcpus is preserved, ie. you can set vcpus to some number of vcpus to be used and the vcpu_avail is set appropriately to use all of them. Only when you use maxvcpus and vcpus new vcpu_avail value is calculated to show PV guest the desired number of vcpus only. It's been tested using RHEL-5 32-bit PV guest with maxvcpus = 4 and vcpus = 2 and also the previous setup of vcpus = 2 only... In both cases I was able to use 'xm vcpu-set {domainId} {numberOfVCPUs}' to increase move vcpu count from 0 to maxvcpus/vcpus so it was working as designed. Michal Signed-off-By: Michal Novotny