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=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 4727AC433DF for ; Tue, 18 Aug 2020 14:30:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22982206DA for ; Tue, 18 Aug 2020 14:30:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mGZ7bHcE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726952AbgHROam (ORCPT ); Tue, 18 Aug 2020 10:30:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51900 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726930AbgHROaZ (ORCPT ); Tue, 18 Aug 2020 10:30:25 -0400 Received: from mail-lj1-x22d.google.com (mail-lj1-x22d.google.com [IPv6:2a00:1450:4864:20::22d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2AC3CC061344; Tue, 18 Aug 2020 07:30:24 -0700 (PDT) Received: by mail-lj1-x22d.google.com with SMTP id h19so21660602ljg.13; Tue, 18 Aug 2020 07:30:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to :content-transfer-encoding; bh=EKmO5OL8YqABBQxdTc7s+i0zzy1xBLouHzrebnJDpis=; b=mGZ7bHcElaXqrCYV9DL1BOj/IuS2bmiyPYX0PqgMOP9WF/77dT1kpyEyyglxYYmB4u EvEBaisupWAJrDa5DhO8+n5lvmQsxZyOM96nzQOaWEakY7evRmrpsxruxbpW1f39pmG8 zYU9WXNjnNjfTv9uvN9T5/dd8ct/pKXRYCTyraUYNAh3C/M6HBtjo9i3gwo/ZnMcuQBK SmhkjHYQtoCe14V6Lakfz729CvVqy8p/SUWutYSruyat+fTgh3IAEsvGMNoqzn7Z5rBO F7SfX8bznQT5If88lPI5JXNGyrpa3w5rdZHQwgxzXdVgu8G4HdE250jxt9HK1GBfQo40 FLpg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to :content-transfer-encoding; bh=EKmO5OL8YqABBQxdTc7s+i0zzy1xBLouHzrebnJDpis=; b=U+8jeX+Z+GvykQohCp6ZuP8lQ5yIU81JmF9/cq602LjOi6gx9bbFlPqg1MmiNQuyfH 4w41kUccHI6OupsfBLLYwgYMDXA/4pywW8j+gIQJHmAcC5Z4gPgyOVMD1p78r4I3K4xy 28ac6sgfRRxN6vu4Uv9H6mkPjJhVSXXDhT7HZR3fKe01RuHwR7HM8yCKAqbZ3nUMqXPP aXZdKd24Hc0d4S4M2PfPlz0McO3XhkBhpUMUQ9wm1hDAvO0Zke51T7Q9RUjjjocMCQKy 6gXAXE8uMLV1K8B/FWwiyqVHTvCjLTxuEXJpeJ1xFvfE6edon22U0/plg+XwtqxT2frI qhWQ== X-Gm-Message-State: AOAM531x+O/Ja0DXbxghacO16a6ps/mq6VzasWmpbrkClrtXHFSajLoy O8tE6ZvxjZMXnrLVLn0sQTEwC9n4DnEBtpJ+pXSssGc4tu4= X-Google-Smtp-Source: ABdhPJwDLwy9lrFbCZHRAPg/5oUtgAIZvmfT4IQOBkQIyITsssC28W0Q8MfrFwEwrIl2E+AXrkgrKVjw+etzb7teu24= X-Received: by 2002:a2e:b174:: with SMTP id a20mr6626678ljm.200.1597761023270; Tue, 18 Aug 2020 07:30:23 -0700 (PDT) MIME-Version: 1.0 From: Muni Sekhar Date: Tue, 18 Aug 2020 20:00:11 +0530 Message-ID: Subject: Scheduler benchmarks To: kernelnewbies , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, I=E2=80=99ve two identical Linux systems with only kernel differences. While doing kernel profiling with perf, I got the below mentioned metrics for Scheduler benchmarks. 1st system (older kernel version compared to the other system) benchmark re= sult: $ perf bench sched messaging -g 64 # Running 'sched/messaging' benchmark: # 20 sender and receiver processes per group # 64 groups =3D=3D 2560 processes run Total time: 2.936 [sec] 2nd system benchmark result: $ perf bench sched messaging -g 64 # Running 'sched/messaging' benchmark: # 20 sender and receiver processes per group # 64 groups =3D=3D 2560 processes run Total time: 10.074 [sec] So as per scheduler benchmark results, clearly a huge difference between two systems. Can anyone suggest to me how to dive deeper to know the root cause for it. Also are there any tunable kernel parameters related to this one? --=20 Thanks, Sekhar