From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753396Ab3IIPDb (ORCPT ); Mon, 9 Sep 2013 11:03:31 -0400 Received: from mail-pd0-f172.google.com ([209.85.192.172]:51522 "EHLO mail-pd0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753117Ab3IIPD3 (ORCPT ); Mon, 9 Sep 2013 11:03:29 -0400 Message-ID: <522DE339.4030004@gmail.com> Date: Mon, 09 Sep 2013 08:03:21 -0700 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Jiri Olsa CC: Peter Zijlstra , linux-kernel@vger.kernel.org, Corey Ashford , Frederic Weisbecker , Ingo Molnar , Namhyung Kim , Paul Mackerras , Arnaldo Carvalho de Melo , Andi Kleen Subject: Re: [PATCHv2 00/25] perf tool: Add support for multiple data file storage References: <1378031796-17892-1-git-send-email-jolsa@redhat.com> <20130909111749.GP31370@twins.programming.kicks-ass.net> <20130909113640.GA16401@krava.redhat.com> <20130909115518.GA26785@twins.programming.kicks-ass.net> <20130909140339.GB16401@krava.redhat.com> <522DD6FF.50107@gmail.com> <20130909143134.GA27974@krava.redhat.com> In-Reply-To: <20130909143134.GA27974@krava.redhat.com> 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 9/9/13 7:31 AM, Jiri Olsa wrote: > On Mon, Sep 09, 2013 at 07:11:11AM -0700, David Ahern wrote: >> On 9/9/13 7:03 AM, Jiri Olsa wrote: >>> my usage currently is to having this running during the day: >>> (well whenever I remember to run it.. ;-) ) >>> >>> [jolsa@krava perf]$ sudo ./perf record -g -M 1m -a >>> >>> and checking report when the system or app get stuck >>> >>> with multiple files I can just easily (or automaticaly) >>> remove old ones without restarting session >> >> Aren't you losing potentially important events by doing that -- >> FORK, COMM, MMAP? > > those are synthesized for each file via synthesize_record > function, see: > > [PATCH 19/25] perf tools: Move synthesizing into single function Ok. haven't had time to look through your 2 large patch sets. Seems like a lot of repetitive work on a loaded system. The overhead of the task events will dominate compared to the samples. > >> >> I have a flight recorder style command that address this problem >> (long-running/daemons) by processing task events and then stashing >> the sample events on a time-ordered list with chopping to maintain >> the time window. > > so far I noticed there could be race among EXIT and remaining > SAMPLE events on another CPU mmap than EXIT event.. ending up > with EXIT being stored in the old file, while SAMPLEs will get > to the new one > > I was thinking about some 'perf daemon' so I dont need to run that > manually.. seems similar to what you did Right now I focus on scheduling events. This latest version of it can be easily recycled for other use cases. Some work would be needed to dump events to a file versus dumping processed information. I am in San Jose this week. Not sure if I will have time to finish it to a point of pushing out patches, but maybe I can push to github in the next couple of days. David