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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A3E6C433EF for ; Mon, 27 Jun 2022 12:34:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234428AbiF0MeX (ORCPT ); Mon, 27 Jun 2022 08:34:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36604 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232608AbiF0MeW (ORCPT ); Mon, 27 Jun 2022 08:34:22 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 409ECBC90; Mon, 27 Jun 2022 05:34:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1656333261; x=1687869261; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=3cZhrIXL/31n4yULxyK6MSoWTderF7rYg/64LrImcrE=; b=l8Ek+mVAIYB77pTxT3xHwJOrlKPN4ZrqO6g4PMZfW3yWZ5dhKW5aRNrY AuhGC9X5i6JisqKxIoQ0kQc1CvRomRcPKcXgpNFdODLhM4x/t5KFa4+Lj FY2ne7/Fbikw+Jwxuxy1H2NrO96+0BxVvPKwEo9oaDo0b0jzoiGMey4s6 zkouTkaHzUMtQB+/b0Kn72CxPzHEmTbkmFqIqq6sNtPdceuoin1DUqPWv TQpOx9K40n0LvlTp5/Nx31mfU0i7SD37c4I34adDkn1I/qhJPa+oTjfhX afsyuaEFkl0fEW/+og9+h9I7aHp5h9FiWeOevMVIVQ6H2nZFN0Cjsdn1u Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10390"; a="367753998" X-IronPort-AV: E=Sophos;i="5.92,226,1650956400"; d="scan'208";a="367753998" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jun 2022 05:34:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.92,226,1650956400"; d="scan'208";a="679565746" Received: from shbuild999.sh.intel.com (HELO localhost) ([10.239.146.138]) by FMSMGA003.fm.intel.com with ESMTP; 27 Jun 2022 05:34:16 -0700 Date: Mon, 27 Jun 2022 20:34:15 +0800 From: Feng Tang To: Eric Dumazet Cc: Shakeel Butt , Linux MM , Andrew Morton , Roman Gushchin , Michal Hocko , Johannes Weiner , Muchun Song , Jakub Kicinski , Xin Long , Marcelo Ricardo Leitner , kernel test robot , Soheil Hassas Yeganeh , LKML , network dev , linux-s390@vger.kernel.org, MPTCP Upstream , "linux-sctp @ vger . kernel . org" , lkp@lists.01.org, kbuild test robot , Huang Ying , Xing Zhengjun , Yin Fengwei , Ying Xu Subject: Re: [net] 4890b686f4: netperf.Throughput_Mbps -69.4% regression Message-ID: <20220627123415.GA32052@shbuild999.sh.intel.com> References: <20220623185730.25b88096@kernel.org> <20220624070656.GE79500@shbuild999.sh.intel.com> <20220624144358.lqt2ffjdry6p5u4d@google.com> <20220625023642.GA40868@shbuild999.sh.intel.com> <20220627023812.GA29314@shbuild999.sh.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org On Mon, Jun 27, 2022 at 10:46:21AM +0200, Eric Dumazet wrote: > On Mon, Jun 27, 2022 at 4:38 AM Feng Tang wrote: [snip] > > > > > > > > Thanks Feng. Can you check the value of memory.kmem.tcp.max_usage_in_bytes > > > > in /sys/fs/cgroup/memory/system.slice/lkp-bootstrap.service after making > > > > sure that the netperf test has already run? > > > > > > memory.kmem.tcp.max_usage_in_bytes:0 > > > > Sorry, I made a mistake that in the original report from Oliver, it > > was 'cgroup v2' with a 'debian-11.1' rootfs. > > > > When you asked about cgroup info, I tried the job on another tbox, and > > the original 'job.yaml' didn't work, so I kept the 'netperf' test > > parameters and started a new job which somehow run with a 'debian-10.4' > > rootfs and acutally run with cgroup v1. > > > > And as you mentioned cgroup version does make a big difference, that > > with v1, the regression is reduced to 1% ~ 5% on different generations > > of test platforms. Eric mentioned they also got regression report, > > but much smaller one, maybe it's due to the cgroup version? > > This was using the current net-next tree. > Used recipe was something like: > > Make sure cgroup2 is mounted or mount it by mount -t cgroup2 none $MOUNT_POINT. > Enable memory controller by echo +memory > $MOUNT_POINT/cgroup.subtree_control. > Create a cgroup by mkdir $MOUNT_POINT/job. > Jump into that cgroup by echo $$ > $MOUNT_POINT/job/cgroup.procs. > > > > The regression was smaller than 1%, so considered noise compared to > the benefits of the bug fix. Yes, 1% is just around noise level for a microbenchmark. I went check the original test data of Oliver's report, the tests was run 6 rounds and the performance data is pretty stable (0Day's report will show any std deviation bigger than 2%) The test platform is a 4 sockets 72C/144T machine, and I run the same job (nr_tasks = 25% * nr_cpus) on one CascadeLake AP (4 nodes) and one Icelake 2 sockets platform, and saw 75% and 53% regresson on them. In the first email, there is a file named 'reproduce', it shows the basic test process: " use 'performane' cpufre governor for all CPUs netserver -4 -D modprobe sctp netperf -4 -H 127.0.0.1 -t SCTP_STREAM_MANY -c -C -l 300 -- -m 10K & netperf -4 -H 127.0.0.1 -t SCTP_STREAM_MANY -c -C -l 300 -- -m 10K & netperf -4 -H 127.0.0.1 -t SCTP_STREAM_MANY -c -C -l 300 -- -m 10K & (repeat 36 times in total) ... " Which starts 36 (25% of nr_cpus) netperf clients. And the clients number also matters, I tried to increase the client number from 36 to 72(50%), and the regression is changed from 69.4% to 73.7% Thanks, Feng > > > > Thanks, > > Feng