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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 8A7CFC433ED for ; Wed, 14 Apr 2021 17:17:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 533D061168 for ; Wed, 14 Apr 2021 17:17:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233670AbhDNRSL (ORCPT ); Wed, 14 Apr 2021 13:18:11 -0400 Received: from foss.arm.com ([217.140.110.172]:59278 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233753AbhDNRSH (ORCPT ); Wed, 14 Apr 2021 13:18:07 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8CF5811B3; Wed, 14 Apr 2021 10:17:45 -0700 (PDT) Received: from e113632-lin (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 3E0033F73B; Wed, 14 Apr 2021 10:17:43 -0700 (PDT) From: Valentin Schneider To: kernel test robot Cc: 0day robot , Vincent Guittot , Dietmar Eggemann , LKML , lkp@lists.01.org, ying.huang@intel.com, feng.tang@intel.com, zhengjun.xing@intel.com, Lingutla Chandrasekhar , Peter Zijlstra , Ingo Molnar , Morten Rasmussen , Qais Yousef , Quentin Perret , Pavan Kondeti , Rik van Riel , aubrey.li@linux.intel.com, yu.c.chen@intel.com Subject: Re: [sched/fair] 38ac256d1c: stress-ng.vm-segv.ops_per_sec -13.8% regression In-Reply-To: <20210414052151.GB21236@xsang-OptiPlex-9020> References: <20210414052151.GB21236@xsang-OptiPlex-9020> Date: Wed, 14 Apr 2021 18:17:38 +0100 Message-ID: <87im4on5u5.mognet@arm.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14/04/21 13:21, kernel test robot wrote: > Greeting, > > FYI, we noticed a -13.8% regression of stress-ng.vm-segv.ops_per_sec due to commit: > > > commit: 38ac256d1c3e6b5155071ed7ba87db50a40a4b58 ("[PATCH v5 1/3] sched/fair: Ignore percpu threads for imbalance pulls") > url: https://github.com/0day-ci/linux/commits/Valentin-Schneider/sched-fair-load-balance-vs-capacity-margins/20210408-060830 > base: https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git 0a2b65c03e9b47493e1442bf9c84badc60d9bffb > > in testcase: stress-ng > on test machine: 96 threads Intel(R) Xeon(R) Gold 6252 CPU @ 2.10GHz with 192G memory > with following parameters: > > nr_threads: 10% > disk: 1HDD > testtime: 60s > fs: ext4 > class: os > test: vm-segv > cpufreq_governor: performance > ucode: 0x5003006 > > That's almost exactly the same result as [1], which is somewhat annoying for me because I wasn't able to reproduce those results back then. Save from scrounging the exact same machine to try this out, I'm not sure what's the best way forward. I guess I can re-run the workload on whatever machines I have and try to spot any potentially problematic pattern in the trace... [1]: http://lore.kernel.org/r/20210223023004.GB25487@xsang-OptiPlex-9020