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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 E5CACC433E1 for ; Tue, 9 Jun 2020 15:29:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C21E52072F for ; Tue, 9 Jun 2020 15:29:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="PxxFU62u" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730811AbgFIP3w (ORCPT ); Tue, 9 Jun 2020 11:29:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47942 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730786AbgFIP3t (ORCPT ); Tue, 9 Jun 2020 11:29:49 -0400 Received: from mail-lf1-x142.google.com (mail-lf1-x142.google.com [IPv6:2a00:1450:4864:20::142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D62BC03E97C for ; Tue, 9 Jun 2020 08:29:49 -0700 (PDT) Received: by mail-lf1-x142.google.com with SMTP id d7so12747203lfi.12 for ; Tue, 09 Jun 2020 08:29:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=J9IVxxdE18kyf3He9rGpIj1hCmIn48AUOA8lzG/AI2M=; b=PxxFU62uc9/YdDEGEwgsByTKQ1jYCPZ7jusRIZFSG9pvy3hsq+s/8Co9l3kPBq+4yb KSRZFG/bZGi2PSSRoGLJ5Cs1ziGss5k51YEgFmxM0cZSSP2YBULLKSWQWnXeUe+ry7M0 pmdxRok/GD324+n8jxEzje9XDjAhqTS4tP2jNjR9p58TsKTFZ1Q0pqviupSfy2DL5L+n 7qYTWPPKYacrcZzgJW6T0l7OpvpGx6LcnQzcGeHghM46NVOZGYzohckpdayCzJreUymH 2sPKOcYFglPVEWN7/5Q6fmaE5HiV/SMWHUGi6dYPRxP2zvErMdFv9OAIWyUK4rbJspnW nnMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=J9IVxxdE18kyf3He9rGpIj1hCmIn48AUOA8lzG/AI2M=; b=m2ORj65Re+kXqk0pCtSMypTipI4Szvn2DDwuSMjtChdUU5Jyr5OFBF3Qv3eXgNGywx BWFceoxiYiyq//rNQ9VDoitsz3pHONjNKYalOMwcZzeEe56EEJfynNL4uLjRr1fOooaD PBZMkTWumkJdZ2dXeS0dHUx/s7oV+o+loDB+kA/TFtXLMFtJ+1q1zPwE3xlseulbvMD+ DI/M6eMsI+DRLkscmfj9T7Os+SzLcTYKSyU8YvjUbW+OuVaUxNQgQdtovyDPu6fzxiVT /fYvakI9UQ9s/XyfTS4l8dw7v/nU7VecjFWRgbz00w5bxaldst2JRpp8VJDta0xNdIZa QmMw== X-Gm-Message-State: AOAM530meH/dRr+OGpnjRKtSlDYPZUzAjE3cID1FgiaM3HHnXABnSH1T zHOltbuh+QB2uISB77gbovTzzlr2qahxkip2hMm3w7rDwJ8= X-Google-Smtp-Source: ABdhPJxdls+n5VYYUq0Wc3bhGAoi+RcxAxDptX5ze7i/Z0PrfNr4h3k3pU9Hw0QalwWSUOwrg+Rh/AgPlcWHQM4Ipb4= X-Received: by 2002:a19:4854:: with SMTP id v81mr15493723lfa.189.1591716587413; Tue, 09 Jun 2020 08:29:47 -0700 (PDT) MIME-Version: 1.0 References: <20200528132327.GB706460@hirez.programming.kicks-ass.net> <20200528155800.yjrmx3hj72xreryh@e107158-lin.cambridge.arm.com> <20200528161112.GI2483@worktop.programming.kicks-ass.net> <20200529100806.GA3070@suse.de> <87v9k84knx.derkling@matbug.net> <20200603101022.GG3070@suse.de> <20200603165200.v2ypeagziht7kxdw@e107158-lin.cambridge.arm.com> <20200605104517.r65dqhzavnnrnfb2@e107158-lin.cambridge.arm.com> In-Reply-To: <20200605104517.r65dqhzavnnrnfb2@e107158-lin.cambridge.arm.com> From: Vincent Guittot Date: Tue, 9 Jun 2020 17:29:35 +0200 Message-ID: Subject: Re: [PATCH 1/2] sched/uclamp: Add a new sysctl to control RT default boost value To: Qais Yousef Cc: Mel Gorman , Patrick Bellasi , Dietmar Eggemann , Peter Zijlstra , Ingo Molnar , Randy Dunlap , Jonathan Corbet , Juri Lelli , Steven Rostedt , Ben Segall , Luis Chamberlain , Kees Cook , Iurii Zaikin , Quentin Perret , Valentin Schneider , Pavan Kondeti , linux-doc@vger.kernel.org, linux-kernel , linux-fs Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org H Qais, Sorry for the late reply. On Fri, 5 Jun 2020 at 12:45, Qais Yousef wrote: > > On 06/04/20 14:14, Vincent Guittot wrote: > > I have tried your patch and I don't see any difference compared to > > previous tests. Let me give you more details of my setup: > > I create 3 levels of cgroups and usually run the tests in the 4 levels > > (which includes root). The result above are for the root level > > > > But I see a difference at other levels: > > > > root level 1 level 2 level 3 > > > > /w patch uclamp disable 50097 46615 43806 41078 > > tip uclamp enable 48706(-2.78%) 45583(-2.21%) 42851(-2.18%) > > 40313(-1.86%) > > /w patch uclamp enable 48882(-2.43%) 45774(-1.80%) 43108(-1.59%) > > 40667(-1.00%) > > > > Whereas tip with uclamp stays around 2% behind tip without uclamp, the > > diff of uclamp with your patch tends to decrease when we increase the > > number of level > > Thanks for the extra info. Let me try this. > > If you can run perf and verify that you see activate/deactivate_task showing up > as overhead I'd appreciate it. Just to confirm that indeed what we're seeing > here are symptoms of the same problem Mel is seeing. I see call to activate_task() for each wakeup of the sched-pipi thread > > > Beside this, that's also interesting to notice the ~6% of perf impact > > between each level for the same image > > Interesting indeed. > > Thanks > > -- > Qais Yousef