From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: How to determine the backing host physical memory for a given guest ? Date: Wed, 09 May 2012 16:46:21 +0300 Message-ID: <4FAA752D.9020905@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: Chegu Vinod Return-path: Received: from mx1.redhat.com ([209.132.183.28]:43775 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756793Ab2EINqb (ORCPT ); Wed, 9 May 2012 09:46:31 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 05/09/2012 04:05 PM, Chegu Vinod wrote: > Hello, > > On an 8 socket Westmere host I am attempting to run a single guest and > characterize the virtualization overhead for a system intensive > workload (AIM7-high_systime) as the size of the guest scales (10way/64G, > 20way/128G, ... 80way/512G). > > To do some comparisons between the native vs. guest runs. I have > been using "numactl" to control the cpu node & memory node bindings for > the qemu instance. For larger guest sizes I end up binding across multiple > localities. for e.g. a 40 way guest : > > numactl --cpunodebind=0,1,2,3 --membind=0,1,2,3 \ > qemu-system-x86_64 -smp 40 -m 262144 \ > <....> > > I understand that actual mappings from a guest virtual address to host physical > address could change. > > Is there a way to determine [at a given instant] which host's NUMA node is > providing the backing physical memory for the active guest's kernel and > also for the the apps actively running in the guest ? > > Guessing that there is a better way (some tool available?) than just > diff'ng the per node memory usage...from the before and after output of > "numactl --hardware" on the host. > Not sure if that's what you want, but there's Documentation/vm/pagemap.txt. -- error compiling committee.c: too many arguments to function