From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D0FBC43381 for ; Thu, 21 Feb 2019 05:46:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 654E72063F for ; Thu, 21 Feb 2019 05:46:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726150AbfBUFqj (ORCPT ); Thu, 21 Feb 2019 00:46:39 -0500 Received: from mga06.intel.com ([134.134.136.31]:14459 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725648AbfBUFqj (ORCPT ); Thu, 21 Feb 2019 00:46:39 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Feb 2019 21:46:38 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.58,393,1544515200"; d="scan'208";a="126059951" Received: from shao2-debian.sh.intel.com (HELO localhost) ([10.239.13.107]) by fmsmga008.fm.intel.com with ESMTP; 20 Feb 2019 21:46:37 -0800 Date: Thu, 21 Feb 2019 13:46:54 +0800 From: kernel test robot To: Wei Yang Cc: Greg Kroah-Hartman , Stephen Rothwell , "Rafael J. Wysocki" , lkp@01.org, "Huang, Ying" , LKML Subject: Re: [LKP] [driver core] 570d020012: will-it-scale.per_thread_ops -12.2% regression Message-ID: <20190221054654.GC28147@shao2-debian> References: <20190218075442.GI29177@shao2-debian> <20190219005945.GA16734@richard> <20190219121904.GA24103@kroah.com> <20190221031049.GE28258@shao2-debian> <20190221034612.GA15147@richard> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190221034612.GA15147@richard> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 21, 2019 at 11:46:12AM +0800, Wei Yang wrote: > On Thu, Feb 21, 2019 at 11:10:49AM +0800, kernel test robot wrote: > >On Tue, Feb 19, 2019 at 01:19:04PM +0100, Greg Kroah-Hartman wrote: > >> On Tue, Feb 19, 2019 at 08:59:45AM +0800, Wei Yang wrote: > >> > On Mon, Feb 18, 2019 at 03:54:42PM +0800, kernel test robot wrote: > >> > >Greeting, > >> > > > >> > >FYI, we noticed a -12.2% regression of will-it-scale.per_thread_ops due to commit: > >> > > > >> > > > >> > >commit: 570d0200123fb4f809aa2f6226e93a458d664d70 ("driver core: move device->knode_class to device_private") > >> > >https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master > >> > > > >> > > >> > This is interesting. > >> > > >> > I didn't expect the move of this field will impact the performance. > >> > > >> > The reason is struct device is a hotter memory than device->device_private? > >> > > >> > >in testcase: will-it-scale > >> > >on test machine: 288 threads Knights Mill with 80G memory > >> > >with following parameters: > >> > > > >> > > nr_task: 100% > >> > > mode: thread > >> > > test: unlink2 > >> > > cpufreq_governor: performance > >> > > > >> > >test-description: Will It Scale takes a testcase and runs it from 1 through to n parallel copies to see if the testcase will scale. It builds both a process and threads based test in order to see any differences between the two. > >> > >test-url: https://github.com/antonblanchard/will-it-scale > >> > > > >> > >In addition to that, the commit also has significant impact on the following tests: > >> > > > >> > >+------------------+---------------------------------------------------------------+ > >> > >| testcase: change | will-it-scale: will-it-scale.per_thread_ops -29.9% regression | > >> > >| test machine | 288 threads Knights Mill with 80G memory | > >> > >| test parameters | cpufreq_governor=performance | > >> > >| | mode=thread | > >> > >| | nr_task=100% | > >> > >| | test=signal1 | > >> > >> Ok, I'm going to blame your testing system, or something here, and not > >> the above patch. > >> > >> All this test does is call raise(3). That does not touch the driver > >> core at all. > >> > >> > >+------------------+---------------------------------------------------------------+ > >> > >| testcase: change | will-it-scale: will-it-scale.per_thread_ops -16.5% regression | > >> > >| test machine | 288 threads Knights Mill with 80G memory | > >> > >| test parameters | cpufreq_governor=performance | > >> > >| | mode=thread | > >> > >| | nr_task=100% | > >> > >| | test=open1 | > >> > >+------------------+---------------------------------------------------------------+ > >> > >> Same here, open1 just calls open/close a lot. No driver core > >> interaction at all there either. > >> > >> So are you _sure_ this is the offending patch? > > > >Hi Greg, > > > >We did an experiment, recovered the layout of struct device. and we > >found the regression is gone. I guess the regession is not from the > >patch but related to the struct layout. > > > > > >tests: 1 > >testcase/path_params/tbox_group/run: will-it-scale/performance-thread-100%-unlink2/lkp-knm01 > > > >570d0200123fb4f8 a36dc70b810afe9183de2ea18f > >---------------- -------------------------- > > %stddev change %stddev > > \ | \ > > 237096 14% 270789 will-it-scale.workload > > 823 14% 939 will-it-scale.per_thread_ops > > > > Do you have the comparison between a36dc70b810afe9183de2ea18f and the one > before 570d020012? testcase/path_params/tbox_group/run: will-it-scale/performance-thread-100%-unlink2/lkp-knm01 4bd4e92cfe6d2af7 a36dc70b810afe9183de2ea18f ---------------- -------------------------- %stddev %change %stddev \ | \ 937.00 +0.2% 939.33 will-it-scale.per_thread_ops 269989 +0.3% 270789 will-it-scale.workload > > > >tests: 1 > >testcase/path_params/tbox_group/run: will-it-scale/performance-thread-100%-signal1/lkp-knm01 > > > >570d0200123fb4f8 a36dc70b810afe9183de2ea18f > >---------------- -------------------------- > > %stddev change %stddev > > \ | \ > > 93.51 ± 3% 48% 138.53 ± 3% will-it-scale.time.user_time > > 186 40% 261 will-it-scale.per_thread_ops > > 53909 40% 75507 will-it-scale.workload > > testcase/path_params/tbox_group/run: will-it-scale/performance-thread-100%-signal1/lkp-knm01 4bd4e92cfe6d2af7 a36dc70b810afe9183de2ea18f ---------------- -------------------------- %stddev %change %stddev \ | \ 266.00 ± 2% -1.6% 261.67 will-it-scale.per_thread_ops 76699 ± 2% -1.6% 75507 will-it-scale.workload > > > >tests: 1 > >testcase/path_params/tbox_group/run: will-it-scale/performance-thread-100%-open1/lkp-knm01 > > > >570d0200123fb4f8 a36dc70b810afe9183de2ea18f > >---------------- -------------------------- > > %stddev change %stddev > > \ | \ > > 447722 22% 546258 ± 10% will-it-scale.time.involuntary_context_switches > > 226995 19% 269751 will-it-scale.workload > > 787 19% 936 will-it-scale.per_thread_ops > > > > testcase/path_params/tbox_group/run: will-it-scale/performance-thread-100%-open1/lkp-knm01 4bd4e92cfe6d2af7 a36dc70b810afe9183de2ea18f ---------------- -------------------------- %stddev %change %stddev \ | \ 944.60 -0.9% 936.00 will-it-scale.per_thread_ops 272252 -0.9% 269751 will-it-scale.workload Best Regards, Rong Chen