From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Question about host CPU usage/allocation by KVM Date: Wed, 18 Apr 2012 18:58:31 +0300 Message-ID: <4F8EE4A7.1030102@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Alexander Lyakas Return-path: Received: from mx1.redhat.com ([209.132.183.28]:3400 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751392Ab2DRP6e (ORCPT ); Wed, 18 Apr 2012 11:58:34 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 04/18/2012 12:54 AM, Alexander Lyakas wrote: > Greetings everybody, > > Can anybody please point me to code/documentation regarding the > following questions I have: > > - What does it actually mean using "-smp N" option, in terms of CPU > sharing between the host and the guest? What does cpu sharing mean? > - How are guest CPUs mapped to host CPUs (if at all)? The host scheduler allocates guest vcpus to host cpus. This allocation changes with demand from other processes (or guests) on the host. > - Is it possible to hard-allocate one or more CPUs to a particular > guest, preventing the host from using them? Look up 'cpusets'. > - Is it possible to limit guest usage of host CPUs? Look up 'cgroups cpu controller'. -- error compiling committee.c: too many arguments to function