From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: KVM PMU virtualization Date: Fri, 26 Feb 2010 18:06:37 +0200 Message-ID: <4B87F18D.5020202@redhat.com> References: <4B86917C.4070102@redhat.com> <20100225173423.GB4246@8bytes.org> <20100226084241.GF15885@elte.hu> <4B87987A.2020302@redhat.com> <20100226104437.GB7463@elte.hu> <4B87AF44.9090702@redhat.com> <20100226114217.GI7463@elte.hu> <4B87B5DE.30503@redhat.com> <20100226120750.GA11578@elte.hu> <4B87BC74.7050207@redhat.com> <20100226133149.GA23422@elte.hu> <4B87CE93.1070906@redhat.com> <4B87D2EA.1090503@redhat.com> <1267194420.22519.605.camel@laptop> <4B87E09C.3080209@redhat.com> <1267196885.22519.643.camel@laptop> <4B87E4B6.2070009@redhat.com> <1267199748.22519.725.camel@laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Jes Sorensen , Ingo Molnar , Joerg Roedel , KVM General , Zachary Amsden , Gleb Natapov , ming.m.lin@intel.com, "Zhang, Yanmin" , Thomas Gleixner , "H. Peter Anvin" , Arjan van de Ven , Fr??d??ric Weisbecker , Arnaldo Carvalho de Melo To: Peter Zijlstra Return-path: Received: from mx1.redhat.com ([209.132.183.28]:41876 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965216Ab0BZQHH (ORCPT ); Fri, 26 Feb 2010 11:07:07 -0500 In-Reply-To: <1267199748.22519.725.camel@laptop> Sender: kvm-owner@vger.kernel.org List-ID: On 02/26/2010 05:55 PM, Peter Zijlstra wrote: > BTW, just wondering, why would a developer be running VTune in a guest > anyway? I'd think that a developer that windows oriented would simply > run windows on his desktop and VTune there. > Cloud. You have an app running somewhere on a cloud, internally or externally (you may not even know). It's running a production workload and it isn't doing well. You can't reproduce it on your desktop ("works for me, now go away"). So you rdesktop to your guest and monitor it. You can't run anything on the host - you don't have access to it, you don't know who admins it (it's a program anyway), "the host" doesn't even exist, the guest moves around whenever the cloud feels like it. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.