Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753882Ab0HSPEh (ORCPT ); Thu, 19 Aug 2010 11:04:37 -0400 Received: from casper.infradead.org ([85.118.1.10]:38596 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753657Ab0HSPEb (ORCPT ); Thu, 19 Aug 2010 11:04:31 -0400 Date: Thu, 19 Aug 2010 12:04:22 -0300 From: Arnaldo Carvalho de Melo To: Christoph Hellwig Cc: Frederic Weisbecker , linux-kernel@vger.kernel.org, Ingo Molnar , Peter Zijlstra Subject: Re: callchain sampling bug in perf? Message-ID: <20100819150422.GA325@ghostprotocols.net> References: <20100815225359.GA32152@infradead.org> <20100819005720.GB5324@nowhere> <20100819085700.GB8782@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100819085700.GB8782@infradead.org> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.19 (2009-01-05) X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2710 Lines: 73 Em Thu, Aug 19, 2010 at 04:57:01AM -0400, Christoph Hellwig escreveu: > On Thu, Aug 19, 2010 at 02:57:22AM +0200, Frederic Weisbecker wrote: > > Hmm, against which tree are you running? I've just tested callchains > > record on random kprobe based tracepoint and it seemed to work well > > on report. > > It's 2.6.36-rc1 + a few filesystem related changes. > > > Could you send me your perf.data and also the resulting archive > > after the following command: "perf archive" ? > > Both attached. [acme@doppio tmp]$ tar xvf perf.data.tar.bz2 -C ~/.debug .build-id/36/4300f12afee3dd5b1a87269d60de586f6b61ce [kernel.kallsyms]/364300f12afee3dd5b1a87269d60de586f6b61ce [acme@doppio tmp]$ [acme@doppio tmp]$ cat /home/acme/.perfconfig [tui] report=off [acme@doppio tmp]$ perf report # Events: 11K cycles # # Overhead Command Shared Object Symbol # ........ ............ ................. ......... # 61.70% python [kernel.kallsyms] [k] xlog_sync 24.05% flush-9:1 [kernel.kallsyms] [k] xlog_sync 7.99% sync [kernel.kallsyms] [k] xlog_sync 2.94% xfssyncd/md1 [kernel.kallsyms] [k] xlog_sync 1.54% compilebench [kernel.kallsyms] [k] xlog_sync 1.31% sh [kernel.kallsyms] [k] xlog_sync 0.23% :3500 [kernel.kallsyms] [k] xlog_sync 0.17% :3496 [kernel.kallsyms] [k] xlog_sync 0.06% :3570 [kernel.kallsyms] [k] xlog_sync 0.01% :3590 [kernel.kallsyms] [k] xlog_sync # # (For a higher level overview, try: perf report --sort comm,dso) # [acme@doppio tmp]$ # yeah, I need to do what we discussed and make tui activation on the command # line, this use case proves it, if it needed proving usefulness at all :-) [acme@doppio tmp]$ cat /home/acme/.perfconfig [tui] report=on [acme@doppio tmp]$ perf report http://vger.kernel.org/~acme/perf/perf-report-tui-callchain-xlog_sync.png So it seems to work (you tell me if the callchains make sense), and the problem is just on the stdio based callchain rendering. Frederic, so it doesn't look like anything in the kernel, just a tools/perf/ problem. I found some issues on the TUI as well, please press the left key some times after expanding some callchains, so that the window can be resized, your workload has just a few top level entries, so the window initially is small, I need to take into account the (to be expanded) callchains and size it properly. - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/