From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750945Ab0CPXOo (ORCPT ); Tue, 16 Mar 2010 19:14:44 -0400 Received: from mail-gx0-f217.google.com ([209.85.217.217]:49901 "EHLO mail-gx0-f217.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750720Ab0CPXOn (ORCPT ); Tue, 16 Mar 2010 19:14:43 -0400 Message-ID: <4BA00F1F.1090907@codemonkey.ws> Date: Tue, 16 Mar 2010 18:07:11 -0500 From: Anthony Liguori User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091209 Fedora/3.0-4.fc12 Lightning/1.0pre Thunderbird/3.0 MIME-Version: 1.0 To: Ingo Molnar CC: Avi Kivity , "Zhang, Yanmin" , Peter Zijlstra , Sheng Yang , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Marcelo Tosatti , oerg Roedel , Jes Sorensen , Gleb Natapov , Zachary Amsden , ziteng.huang@intel.com, Arnaldo Carvalho de Melo , =?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?= Subject: Re: [PATCH] Enhance perf to collect KVM guest os statistics from host side References: <20100316102052.GC10069@elte.hu> <4B9F603B.4080004@redhat.com> <20100316105021.GA14344@elte.hu> <4B9F671D.5060001@redhat.com> <20100316112500.GA5337@elte.hu> <4B9F77E7.2060101@redhat.com> <20100316122903.GA8831@elte.hu> <4B9F7C6A.3070207@redhat.com> <20100316130840.GA24808@elte.hu> <4B9FBA8B.8020200@codemonkey.ws> <20100316173940.GA23859@elte.hu> In-Reply-To: <20100316173940.GA23859@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/16/2010 12:39 PM, Ingo Molnar wrote: >> If we look at the use-case, it's going to be something like, a user is >> creating virtual machines and wants to get performance information about >> them. >> >> Having to run a separate tool like perf is not going to be what they would >> expect they had to do. Instead, they would either use their existing GUI >> tool (like virt-manager) or they would use their management interface >> (either QMP or libvirt). >> >> The complexity of interaction is due to the fact that perf shouldn't be a >> stand alone tool. It should be a library or something with a programmatic >> interface that another tool can make use of. >> > But ... a GUI interface/integration is of course possible too, and it's being > worked on. > > perf is mainly a kernel developer tool, and kernel developers generally dont > use GUIs to do their stuff: which is the (sole) reason why its first ~850 > commits of tools/perf/ were done without a GUI. We go where our developers > are. > > In any case it's not an excuse to have no proper command-line tooling. In fact > if you cannot get simpler, more atomic command-line tooling right then you'll > probably doubly suck at doing a GUI as well. > It's about who owns the user interface. If qemu owns the user interface, than we can satisfy this in a very simple way by adding a perf monitor command. If we have to support third party tools, then it significantly complicates things. Regards, Anthony Liguori > Ingo >