From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: Getting started with perf; a couple of questions Date: Fri, 07 Jun 2013 18:08:53 -0600 Message-ID: <51B27615.3090504@gmail.com> References: <51A83824.1090907@gmail.com> <51B09633.2040204@gmail.com> <51B1F6C5.3060302@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f51.google.com ([209.85.160.51]:37530 "EHLO mail-pb0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753181Ab3FHAI5 (ORCPT ); Fri, 7 Jun 2013 20:08:57 -0400 Received: by mail-pb0-f51.google.com with SMTP id um15so5268493pbc.10 for ; Fri, 07 Jun 2013 17:08:56 -0700 (PDT) In-Reply-To: Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: Andrew Davidoff Cc: linux-perf-users@vger.kernel.org On 6/7/13 5:49 PM, Andrew Davidoff wrote: > You are correct that the Ubuntu 10.04 host that doesn't seem to be > recording properly is running a 2.6.32 kernel (2.6.32-47-server from > Ubuntu). The invocation of perf record is the same as described for > the CentOS VM (i.e. I am not using -p, and would like to not use -a, > though -a is the only way I'm getting samples recorded for > ). CentOS 6 has newer perf code than its kernel version suggests -- compliments of the RHEL backporting Jiri does. > > I had moved to building a newer version of perf than the one that came > from the Ubuntu 10.04 repo (linux-tools-common) because that one > appeared ancient based on the output it was generating, and reports > version as 0.0.2.PERF (though the binary is installed as > /usr/bin/perf_2.6.32-47). perf record does record data with that > version, but it looks like (via perf report) that it's data only for > one event even when multiple are passed, and that event isn't labeled > in the report, so at a glance I am not sure which it is. If the original perf command works but newer versions do not then the compatibility wheels have fallen off somewhere along the line. Most likely CentOS 6 works b/c of the backports. David > > Anyway, for now I'm not worrying about getting this working on this > particular version of Ubuntu, but I appreciate all your help. If I > decide to dig further I'll start iterating through the versions you > suggested and see where things get extra broken. > > Andy >