Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758195AbaFSQ2t (ORCPT ); Thu, 19 Jun 2014 12:28:49 -0400 Received: from mga01.intel.com ([192.55.52.88]:37670 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757558AbaFSQ2r (ORCPT ); Thu, 19 Jun 2014 12:28:47 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,507,1400050800"; d="scan'208";a="550469789" Date: Fri, 20 Jun 2014 00:28:42 +0800 From: Fengguang Wu To: Yoshihiro YUNOMAE Cc: Jet Chen , LKML , lkp@01.org, Steven Rostedt Subject: Re: [tracing] 939c7a4f04f: -46.4% cpuidle.C3-IVT.time Message-ID: <20140619162842.GB10268@localhost> References: <53A10460.1040705@intel.com> <53A27D66.6070409@hitachi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <53A27D66.6070409@hitachi.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Yoshihiro, On Thu, Jun 19, 2014 at 03:04:22PM +0900, Yoshihiro YUNOMAE wrote: > Hi Jet, > > Thank you for your report. > I have some questions for your test. > > 1. Did you enable ftrace? Yes, ftrace is enabled. Attached is the kernel config. > This patch added a feature for ftrace. If you disabled ftrace in > this test, my patch will not affect the system. Moreover, in my patch, > arrays for saved_cmdlines were just changed from using static global > variables to using kmalloc() on default setting. So, even if you enabled > ftrace, this patch will not induce a big problem, I think. Agreed, the patch itself looks good. Unfortunately sometimes a small change in one place may lead to subtle changes in other places due to data alignment etc. effects. > 2. How did you test it and what does the result mean? > Please tell me the workload, how to calculate the score, > system settings, etc... Workload is aim7's brk_test case, running on an Ivy Bridge-EX machine. However it's not aim7's throughput that's regressed, but there are changes in the C3 state, number of RCU softirqs and power consumption etc. Thanks, Fengguang > Thanks, > Yoshihiro YUNOMAE > > (2014/06/18 12:15), Jet Chen wrote: > >Hi Yoshihiro, > > > >FYI, we noticed the below changes on > > > >commit 939c7a4f04fcd2162109744e8bf88194948a6e65 ("tracing: Introduce > >saved_cmdlines_size file") > > > >test case: brickland3/aim7/3000-brk_test > > > >beba4bb096201ce 939c7a4f04fcd2162109744e8 > >--------------- ------------------------- > > 352643 ~40% -46.4% 189136 ~15% TOTAL cpuidle.C3-IVT.time > > 750 ~ 2% -13.3% 650 ~ 2% TOTAL vmstat.procs.b > > 362016 ~ 3% -6.0% 340296 ~ 3% TOTAL > >proc-vmstat.pgmigrate_success > > 362016 ~ 3% -6.0% 340296 ~ 3% TOTAL > >proc-vmstat.numa_pages_migrated > > 1642328 ~ 3% +13.3% 1860721 ~ 2% TOTAL softirqs.RCU > > 2278829 ~ 2% -14.0% 1959647 ~ 2% TOTAL > >time.voluntary_context_switches > > 207 ~ 0% -10.4% 185 ~ 0% TOTAL time.user_time > > ~ 0% +8.5% ~ 0% TOTAL turbostat.RAM_W > > 4418246 ~ 3% -6.4% 4136447 ~ 1% TOTAL time.minor_page_faults > > ~ 0% +3.4% ~ 0% TOTAL turbostat.Cor_W > > ~ 0% +3.0% ~ 0% TOTAL turbostat.Pkg_W > > 11354889 ~ 0% +2.0% 11579897 ~ 0% TOTAL > >time.involuntary_context_switches > > > >Legend: > > ~XX% - stddev percent > > [+-]XX% - change percent > > > > > > time.voluntary_context_switches > > > > 2.4e+06 > >++---------------------------------------------------*------------+ > > *.. *.. .. > >.. | > > 2.3e+06 ++ .*.. *.. .. > >* | > > | *..*. . .*.. .. * *.. + > >*.. *..* > > | *. * . .*..*.. + > >.. | > > 2.2e+06 ++ *..*. * > >* | > > > >| | > > 2.1e+06 > >++ | > > > >| | > > 2e+06 O+ O O > >O | > > | O O O > >O | > > | O O O O > >O | > > 1.9e+06 ++ O O O > >O | > > | O O > >O | > > 1.8e+06 > >++----------------------------------------------------------------+ > > > > > > turbostat.Pkg_W > > > > ++--------------------------------------------------------------------+ > > O+ O O O O O | > > | O O O O O O O O O O O O | > > ++ O O | > > ++ | > > ++ | > > ++ | > > | | > > ++ | > > ++ | > > ++ *.. .*.. | > > *+.*... .. *...*. *...*..*..*...*..*.. ..*.. *...*..*..*...*..* > > | * *. .. | > > ++ * | > > ++--------------------------------------------------------------------+ > > > > > > turbostat.Cor_W > > > > ++--------------------------------------------------------------------+ > > O+ O O O O O O O O O | > > | O O O O O O O O O O | > > ++ | > > ++ | > > | | > > ++ | > > ++ | > > ++ | > > | | > > ++ *.. | > > *+.*... .. *...*..*..*...*..*..*...*..*.. ..*.. *... .*..*...*..* > > | * *. .. *. | > > ++ * | > > ++--------------------------------------------------------------------+ > > > > > > turbostat.RAM_W > > > > ++---------------------------------------------------------------------+ > > | O O O O O O O O | > > O+ O O O O O O O O O O | > > | O | > > ++ | > > | | > > ++ | > > | | > > ++ | > > | * | > > ++ .. + *.. | > > | .*..* + *.. *.. + ..*..*.. .*... | > > ++ .. + .. .. . + *. *...*. *..* > > *..*...*..* * *...* * | > > ++---------------------------------------------------------------------+ > > > > > > [*] bisect-good sample > > [O] bisect-bad sample > > > > > >Disclaimer: > >Results have been estimated based on internal Intel analysis and are > >provided > >for informational purposes only. Any difference in system hardware or > >software > >design or configuration may affect actual performance. > > > >Thanks, > >Jet > > > > > > -- > Yoshihiro YUNOMAE > Software Platform Research Dept. Linux Technology Center > Hitachi, Ltd., Yokohama Research Laboratory > E-mail: yoshihiro.yunomae.ez@hitachi.com > -- 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/