Received: by 2002:a05:6a11:4021:0:0:0:0 with SMTP id ky33csp393237pxb; Thu, 23 Sep 2021 02:24:03 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwqFUHXExJbmwRd3+Z5rkklhRpFGG9B7OKEXVYfuYdEDrdZj1GLPwWCInkKdms21oKznick X-Received: by 2002:a6b:ef10:: with SMTP id k16mr2931409ioh.210.1632389043299; Thu, 23 Sep 2021 02:24:03 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1632389043; cv=none; d=google.com; s=arc-20160816; b=ADS6Fxe9QC6SQWw0OckheXtM2BI8kGZhIfH1ftHjJd2rTHx/HyD/aXZ6YAFJe5euGN ot5poo/844Xotkr4Ph+f/A9hKSxmazshjJcywFXSDGzlWTvZc1of9FJC5/xlOWIfsQHA +EZkw7lgcSLxO/ZUBZfNgZ2ZIBXbRlaBRBuxHfzZh7PUdgXa+YbytjXKVi2HFP87BEGm VtCWiQ+gLopQ2G58NI9UcpEbPuxSkbK4YBV1o0eIZuWbHcX/4Vo7gXAqP6PNSj9RP89I hgkCBghyVOYcHRVtwCSt84pHnlEaT8ArXq8LYq7I5vA0g+o8wRKYvw+AtiAxihe19sI/ tLAQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:date:cc:to:from:subject :message-id:dkim-signature; bh=fM6ANEDcCneFqIjLQPRhCGq89U2ItzH94JV4HqtmeQY=; b=EuqkbHK5u2Fh/eTd5CC0eSxtRIq1TOnndEPfFxYvELJGu1GjKGxClmaDtk2PJUvZen ONsWkXUoac+2j1OYiRdavm7dANGsH7bnQuVRwYlaDIWNuxHJQsNHtVHxQP6UgoNCjnRJ J9JOZqnvzPhXVTJjZaYinH/IpoKazLiK13+oa6PBDxzlUP089bMrk7cAX60jm6TLfNB2 +zTXgS3MvAqzQ/e5qSd/Z76UqYl3G3bzqDPwW5gR2j3T2kXpAvq/BjIaQX3wU2kppAoz zZim+eHqvonbySqmUTA5mueKzH7/BRabGaBmgYLhUVN14Rq/CO3UEG3eOaMWt78gL207 oXsw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmx.net header.s=badeba3b8450 header.b=Wd6D97bu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=gmx.de Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id g6si3893556ila.86.2021.09.23.02.23.52; Thu, 23 Sep 2021 02:24:03 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@gmx.net header.s=badeba3b8450 header.b=Wd6D97bu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=gmx.de Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240152AbhIWJYF (ORCPT + 99 others); Thu, 23 Sep 2021 05:24:05 -0400 Received: from mout.gmx.net ([212.227.15.15]:39245 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239965AbhIWJYE (ORCPT ); Thu, 23 Sep 2021 05:24:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1632388920; bh=kg2X/33R3HpULtgGMrnIJ3mpCCH8dRU6dKWBGjFCbcc=; h=X-UI-Sender-Class:Subject:From:To:Cc:Date:In-Reply-To:References; b=Wd6D97buHcpeM5C9OaH6mBRlnawOHWnVRmwDHzQnyinaB4DBGvZJH/I9qJLvDwOho /gpsDJefssoDB8bjFbSve/BVjKU+BZNqWMcF84FZFVcNos8iLldsLkwX0JgKzmROn4 AIZnBi0Up0+2b3FrJTCyuF4XTcADdd5gOP19VfMg= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from homer.fritz.box ([185.221.149.175]) by mail.gmx.net (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1N0FxV-1mp8hT1RUl-00xGMP; Thu, 23 Sep 2021 11:22:00 +0200 Message-ID: <50400427070018eff83b0782d2e26c0cc9ff4521.camel@gmx.de> Subject: Re: [PATCH 2/2] sched/fair: Scale wakeup granularity relative to nr_running From: Mike Galbraith To: Vincent Guittot Cc: Mel Gorman , Peter Zijlstra , Ingo Molnar , Valentin Schneider , Aubrey Li , Barry Song , Srikar Dronamraju , LKML Date: Thu, 23 Sep 2021 11:21:58 +0200 In-Reply-To: References: <20210920142614.4891-1-mgorman@techsingularity.net> <20210920142614.4891-3-mgorman@techsingularity.net> <22e7133d674b82853a5ee64d3f5fc6b35a8e18d6.camel@gmx.de> <20210921103621.GM3959@techsingularity.net> <20210922132002.GX3959@techsingularity.net> <20210922150457.GA3959@techsingularity.net> <20210922173853.GB3959@techsingularity.net> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:7kfjVT+3Odk2NlZvSGf0pS+jISsoalbLGF7/wHC7Fpqfsd1V4Mv bfS+eTFqtOkL1CZ7al7yveBmYHRIXdZ8Cy/nFn/1Izg+80cfhRDV94kyATCHkHnJVHND9cp zfoj+6nWrhclPHuzInuvuMXtqU3+2ZTedDh5fSEmcMiFenHwrc4OYMQGuqTrncoQWoJIRZD I2eX2cElk1YXfRpk1ZIIg== X-Spam-Flag: NO X-UI-Out-Filterresults: notjunk:1;V03:K0:vd/QnmmMMow=:bxeBdq2phMXcEO8/VKiPjG A8NgZKtUNkTrk25GtOepUfwDTwYRTylAyaDeb9/NfwQ/RGcHUYNxvLP48z3YVBP0SjhThTkbQ f2wplkLZfnSuY+5vNr33KIBNKFRLChLF3DG6qsMJDETHfCStM6Uf6YxBTo4ks4cyu3jQ8CUUX iJAarAVlWEx4uBew2qdgJhNUjRY44jPGhmZL63iiTPmmIAxTpmLydEIllrM7k9K8WdXQnjxdt AV3rooe2K3+6ItI41vfDImhkwtxPMLf0iDnwZyEIG31RjYhr9CaaVxbP0pf1ibvU3RzogttMH awe8knNLM9ajwixI3LR0chtJuy2S6NLskmBuJxDt2bHQ2yi51wq4tXKj/oi/3o8JQpvRCP3AO iw368JLnt+4nHExDsg4V4Qanz4T3MxgNqZx2CcNOISBwHua34Ab6V2/ayrxZxTDHNeDmo//se ppqB+sJ8sfPG+/87/dV0oCXQz2Q24n6djJY0ufFbdXlbK01OqoWQOuJqfpLjQW/LqEcnb6c8/ slP2mqX8I4Z3AO7CCZ+5XKOzj2d5n04ieVQVf/Oa3771WWaW91hxvreKyGXiePswHQIISO4fP Cjdiq52yXmdr41bI3vFzDk1UhH1alcqO8t8smlllBcyv1yjsZWPk2Cb4CtKu0tf+NKRNwdujO gtaq/3o/xSynvzQCi7odO/OuRwGaPGxs9CWhaJCj8t5TT5T1QzrvqDSTsVFvpBRyI3V+6trjt 0LSHCSr36VHZgVPQ2pyegM4zZSI42smbbcfOvZoTg1zWDeM6nbfkWUn3Ul16Pq1apdY57pPSg LOFQV1qDFi3/pzd3psmFW4q+KKRdGiwfJtTLUHG37PpH8XuDEHXIJp42N064XQdajMnlcoRbq KouDy7V1Zp6/lJpULoD0OQPGHYY+O0O74uWAJasI3vvpjbJZU+6R5MIK0hTf8TTrhU2PWB6iv otmf9bDfZ8RqKxozcVJQmL6i653EzP1rx0jtymy4eCGLxkhI6OFGir3F6LxHBFXnZWj5w4M3B VmAT2L/Px9pX+m0GdaaJt5VggiVZfLMroZKaWFskgUS/5UQ+l9yXUAyEddcrGKFQLtpgC3eTZ KIjSTucuF3CPCI= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2021-09-23 at 10:40 +0200, Vincent Guittot wrote: > > a 100us value should even be enough to fix Mel's problem without > impacting common wakeup preemption cases. It'd be nice if it turn out to be something that simple, but color me skeptical. I've tried various preemption throttling schemes, and while it was trivial to get promising results, my scheme always managed to harm something. Everything I ever tried, I ended up tossing. -Mike