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=-7.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 B26D5C2BA83 for ; Fri, 14 Feb 2020 12:02:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D866222C2 for ; Fri, 14 Feb 2020 12:02:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729064AbgBNMCD (ORCPT ); Fri, 14 Feb 2020 07:02:03 -0500 Received: from mga17.intel.com ([192.55.52.151]:21801 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728036AbgBNMCD (ORCPT ); Fri, 14 Feb 2020 07:02:03 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Feb 2020 04:02:03 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,440,1574150400"; d="scan'208";a="434772638" Received: from rongch2-mobl.ccr.corp.intel.com (HELO [10.249.193.108]) ([10.249.193.108]) by fmsmga006.fm.intel.com with ESMTP; 14 Feb 2020 04:02:01 -0800 Subject: Re: [perf/x86/amd] 471af006a7: will-it-scale.per_process_ops -7.6% regression To: Peter Zijlstra Cc: Kim Phillips , LKML , Linus Torvalds , lkp@lists.01.org References: <20200212113514.GT12867@shao2-debian> <20200212121830.GR14897@hirez.programming.kicks-ass.net> From: "Chen, Rong A" Message-ID: Date: Fri, 14 Feb 2020 20:02:01 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200212121830.GR14897@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/12/2020 8:18 PM, Peter Zijlstra wrote: > On Wed, Feb 12, 2020 at 07:35:14PM +0800, kernel test robot wrote: >> Greeting, >> >> FYI, we noticed a -7.6% regression of will-it-scale.per_process_ops due to commit: >> >> >> commit: 471af006a747f1c535c8a8c6c0973c320fe01b22 ("perf/x86/amd: Constrain Large Increment per Cycle events") >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master >> >> in testcase: will-it-scale >> on test machine: 88 threads Intel(R) Xeon(R) CPU E5-2699 v4 @ 2.20GHz with 128G memory > That commit only changes code relevant to AMD machines; give you have > this result on an Intel machine makes me think the bisect is flawed. Hi, Sorry for the inconvenience, the regression is stable on our platform, we're investigating it. Best Regards, Rong Chen