From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Wiki docs on counting and tracing KVM perf events Date: Thu, 20 May 2010 15:37:53 +0300 Message-ID: <4BF52D21.6090407@redhat.com> References: <4BEC1345.7040408@redhat.com> <4BF4EF97.5060705@redhat.com> <4BF4F07F.4020007@redhat.com> <4BF4F1D1.6030203@redhat.com> <4BF518C1.60304@redhat.com> <4BF519FE.6040208@redhat.com> <4BF527BC.2030709@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Jes Sorensen , kvm To: Stefan Hajnoczi Return-path: Received: from mx1.redhat.com ([209.132.183.28]:44212 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752558Ab0ETMh7 (ORCPT ); Thu, 20 May 2010 08:37:59 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 05/20/2010 03:24 PM, Stefan Hajnoczi wrote: > On Thu, May 20, 2010 at 1:14 PM, Avi Kivity wrote: > >>> echo 1>/sys/kernel/debug/tracing/events/kvm/enable >>> cat /sys/kernel/debug/tracing/trace_pipe>results/trace& >>> >> perf will enable the events by itself (no?), so all you need is is the perf >> call in the middle. >> > Yes, it will enable events. However, I am also generating a > kvm_trace-like log using trace_pipe. On this box I couldn't get perf > trace working so I used trace_pipe for the kvm_trace-equivalent and > perf stat for the kvm_stat equivalent. > Ah. There's the new shiny trace_cmd as well. If you're getting a (binary) trace, runing perf stat is redundant since it contains the same data. -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.