From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752395AbaDWEt1 (ORCPT ); Wed, 23 Apr 2014 00:49:27 -0400 Received: from lgeamrelo01.lge.com ([156.147.1.125]:49751 "EHLO lgeamrelo01.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752183AbaDWEtW (ORCPT ); Wed, 23 Apr 2014 00:49:22 -0400 X-Original-SENDERIP: 10.177.220.181 X-Original-MAILFROM: namhyung@gmail.com From: Namhyung Kim To: Ingo Molnar Cc: Arnaldo Carvalho de Melo , Jiri Olsa , Peter Zijlstra , Paul Mackerras , Namhyung Kim , LKML , David Ahern , Andi Kleen Subject: Re: [PATCHSET 0/9] perf tools: Fixup for the --percentage change References: <1398156591-11001-1-git-send-email-namhyung@kernel.org> <20140422095557.GB10813@gmail.com> Date: Wed, 23 Apr 2014 13:49:05 +0900 In-Reply-To: <20140422095557.GB10813@gmail.com> (Ingo Molnar's message of "Tue, 22 Apr 2014 11:55:57 +0200") Message-ID: <87k3agsla6.fsf@sejong.aot.lge.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ingo, On Tue, 22 Apr 2014 11:55:57 +0200, Ingo Molnar wrote: > I gave it some quick testing and after fixing a trivial merge conflict > in tools/lib/lockdep/Makefile all seems to be working fine. Thanks for testing! > > But while looking at it I remembered one of my old UI complains about > perf top and report, the hard to read nature of: > > Event count (approx.): 226958779 > > the values displayed are typically way too large to be easily human > readable. More importantly, they are also nonsensical! That we have a > sampling interval and can sum up all the intervals sampled has very > little meaning to the overwhelming majority of humans looking at the > data. > > And printing that just spams the visual field and confuses people. > > People care about the quality and speed of sampling itself, not > directly the interval of sampling (which will often be variable with > auto-freq sampling). You meant 'period' by 'interval', right? There's --show-total-period option (should be equivalent to -F period later) in perf report, so there might be people want to see the numbers IMHO. > > So instead of: > > Samples: 42K of event 'cycles', Event count (approx.): 226958779 > > How about only printing this in 'perf top' and 'perf report': > > Captured 42.1K 'cycles' event samples > > Note the extra decimal (which helps monitor smaller changes as well), > and note the different wording. > > Thoughts? Well, I'm okay to add the extra decimal, but it seems that it only makes sense when the unit is 'K'.. And I think it might be worth adding filtered sample count as well if filtering is enabled something like: Captured 13.2K/42.1K 'cycles' event samples Thanks, Namhyung