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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 1FFE9C00307 for ; Mon, 9 Sep 2019 06:07:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F39282067D for ; Mon, 9 Sep 2019 06:07:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727597AbfIIGHD (ORCPT ); Mon, 9 Sep 2019 02:07:03 -0400 Received: from mga05.intel.com ([192.55.52.43]:17442 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726646AbfIIGHD (ORCPT ); Mon, 9 Sep 2019 02:07:03 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Sep 2019 23:07:02 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,483,1559545200"; d="scan'208";a="186411116" Received: from shao2-debian.sh.intel.com (HELO [10.239.13.6]) ([10.239.13.6]) by orsmga003.jf.intel.com with ESMTP; 08 Sep 2019 23:07:00 -0700 Subject: Re: [xfs] 610125ab1e: fsmark.app_overhead -71.2% improvement To: Dave Chinner Cc: "Darrick J. Wong" , Christoph Hellwig , LKML , linux-xfs@vger.kernel.org, lkp@01.org References: <20190909015849.GN15734@shao2-debian> <20190909053236.GP2254@rh> From: Rong Chen Message-ID: Date: Mon, 9 Sep 2019 14:06:54 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190909053236.GP2254@rh> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Hi Dave, On 9/9/19 1:32 PM, Dave Chinner wrote: > On Mon, Sep 09, 2019 at 09:58:49AM +0800, kernel test robot wrote: >> Greeting, >> >> FYI, we noticed a -71.2% improvement of fsmark.app_overhead due to commit: > A negative improvement? That's somewhat ambiguous... Sorry for causing the misunderstanding, it's a improvement not a regression. > >> 0e822255f95db400 610125ab1e4b1b48dcffe74d9d8 >> ---------------- --------------------------- >> %stddev %change %stddev >> \ | \ >> 1.095e+08 -71.2% 31557568 fsmark.app_overhead >> 6157 +95.5% 12034 fsmark.files_per_sec > So, the files/s rate doubled, and the amount of time spent in > userspace by the fsmark app dropped by 70%. > >> 167.31 -47.3% 88.25 fsmark.time.elapsed_time >> 167.31 -47.3% 88.25 fsmark.time.elapsed_time.max > Wall time went down by 50%. > >> 91.00 -8.8% 83.00 fsmark.time.percent_of_cpu_this_job_got >> 148.15 -53.2% 69.38 fsmark.time.system_time > As did system CPU. > > IOWs, this change has changed create performance by a factor of 4 - > the file create is 2x faster for half the CPU spent. > > I don't think this is a negative improvement - it's a large positive > improvement. I suspect that you need to change the metric > classifications for this workload... To avoid misunderstanding, we'll use fsmark.files_per_sec instead of fsmark.app_overhead in the subject. Best Regards, Rong Chen