From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932464AbdJYJCM (ORCPT ); Wed, 25 Oct 2017 05:02:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41316 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932272AbdJYJCG (ORCPT ); Wed, 25 Oct 2017 05:02:06 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 6FB83683F5 Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx09.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=jolsa@redhat.com Date: Wed, 25 Oct 2017 11:02:02 +0200 From: Jiri Olsa To: Namhyung Kim Cc: Ingo Molnar , Arnaldo Carvalho de Melo , "Liang, Kan" , "mingo@redhat.com" , "linux-kernel@vger.kernel.org" , "peterz@infradead.org" , "jolsa@kernel.org" , "wangnan0@huawei.com" , "hekuang@huawei.com" , "alexander.shishkin@linux.intel.com" , "Hunter, Adrian" , "ak@linux.intel.com" , kernel-team@lge.com Subject: Re: [PATCH V3 0/6] event synthesization multithreading for perf record Message-ID: <20171025090201.GF22394@krava> References: <1508529934-369393-1-git-send-email-kan.liang@intel.com> <20171023114822.ijbixdkhysinlwqv@gmail.com> <37D7C6CF3E00A74B8858931C1DB2F077537D874E@SHSMSX103.ccr.corp.intel.com> <20171024092200.wef6b66ecmhrvaja@gmail.com> <20171024114755.GA2716@krava> <20171024125944.uswroptykcqrgjox@gmail.com> <20171024130849.GD7045@kernel.org> <20171024132523.u6esbinw4i3vo3yv@gmail.com> <20171025023539.GE12785@sejong> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171025023539.GE12785@sejong> User-Agent: Mutt/1.9.1 (2017-09-22) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Wed, 25 Oct 2017 09:02:06 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 25, 2017 at 11:35:39AM +0900, Namhyung Kim wrote: > Hi Ingo, > > On Tue, Oct 24, 2017 at 03:25:23PM +0200, Ingo Molnar wrote: > > > > * Arnaldo Carvalho de Melo wrote: > > > > > Em Tue, Oct 24, 2017 at 02:59:44PM +0200, Ingo Molnar escreveu: > > > > > > > > * Jiri Olsa wrote: > > > > > > > > > I recently made some changes on threaded record, which are based > > > > > on Namhyungs time* API, which is needed to read/sort the data afterwards > > > > > > > > > > but I wasn't able to get any substantial and constant reduce of LOST events > > > > > and then I got sidetracked and did not finish, but it's in here: > > > > > > > > So, in the context of system-wide profiling, the way that would work best I think > > > > is the following: > > > > > > > > thread #0 binds itself to CPU#0 (via sched_setaffinity) and creates a per-CPU event on CPU#0 > > > > thread #1 binds itself to CPU#1 (via sched_setaffinity) and creates a per-CPU event on CPU#1 > > > > thread #2 binds itself to CPU#2 (via sched_setaffinity) and creates a per-CPU event on CPU#2 > > > > > > Right, that is how I think it should be done as well, and those will > > > just dump on separate files, in a per session directory, with an extra > > > file for the session details, in what is now the header. > > > > Yes. Also note how easy to examine such a directory structure is - I'd suggest > > making all the session details textual eventually. I.e. only the ring-buffers > > should be binary, the rest should be arch-independent text encoding. > > > > It's also very extensible. > > Agreed. > > Also for multithread work, conversion to directory should be the first > step IMHO. yes, but thats what we already have with yours (Namhyung's) HEADER_DATA_INDEX jirka