From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <daahern@cisco.com>
Subject: Re: [PATCH v2 00/11] KVM in-guest performance monitoring
Date: Thu, 16 Jun 2011 08:19:06 -0600
Message-ID: <4DFA10DA.4030704@cisco.com>
References: <1307972106-2468-1-git-send-email-avi@redhat.com> <4DF66B1A.6060606@cisco.com> <4DF71DA3.2080300@redhat.com> <4DF7972F.3040103@cisco.com> <4DF79941.9050705@siemens.com> <4DF79B6F.10102@cisco.com> <4DF79EFE.1050201@cisco.com> <4DF7A436.8090308@cisco.com> <4DF873FD.6040903@redhat.com> <4DF8A82F.5090900@cisco.com> <4DF8B1F8.6030502@redhat.com> <4DF8D8FE.2080808@cisco.com> <4DF8DD87.8040905@redhat.com> <4DF8E328.6070708@cisco.com> <4DFA0AC4.9050702@redhat.com> <4DFA0E56.70301@cisco.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: Marcelo Tosatti <mtosatti@redhat.com>, kvm@vger.kernel.org,
	Ingo Molnar <mingo@elte.hu>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
To: Avi Kivity <avi@redhat.com>
Return-path: <kvm-owner@vger.kernel.org>
Received: from sj-iport-2.cisco.com ([171.71.176.71]:26156 "EHLO
	sj-iport-2.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1758085Ab1FPOTI (ORCPT <rfc822;kvm@vger.kernel.org>);
	Thu, 16 Jun 2011 10:19:08 -0400
In-Reply-To: <4DFA0E56.70301@cisco.com>
Sender: kvm-owner@vger.kernel.org
List-ID: <kvm.vger.kernel.org>

On 06/16/2011 08:08 AM, David Ahern wrote:
> Command:
>   perf stat -e instructions  openssl speed aes

Hmm.. this might be the wrong benchmark for this. I thought
openssl-speed was a purely CPU intensive benchmark which should have
fairly similar performance numbers in both host and guest. I seem to
recall this as true 2 or so years ago, but that is not the case with
3.0-rc2 and F14.

Using a benchmark Vince W. wrote seems better:
  http://www.csl.cornell.edu/~vince/projects/perf_counter/million.s

perf stat -e instructions ./million

 Performance counter stats for './million':

         1,113,650 instructions              #    0.00  insns per cycle


David


> 
> Guest:
>    135,522,189,056 instructions              #    0.00  insns per cycle
> 
> 
> Host:
>    346,082,922,185 instructions              #    0.00  insns per cycle
> 
> 
> Adding '--no-scale' to the perf-stat had no effect on the relative
> difference.
> 
> David