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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 B1E98C10F14 for ; Tue, 8 Oct 2019 17:55:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A7B82054F for ; Tue, 8 Oct 2019 17:55:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="WI9aVGwm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729350AbfJHRz5 (ORCPT ); Tue, 8 Oct 2019 13:55:57 -0400 Received: from merlin.infradead.org ([205.233.59.134]:42842 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726822AbfJHRz5 (ORCPT ); Tue, 8 Oct 2019 13:55:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=XOAM8DrmdqvOxvYQbnHko0mZQJE/UmKN0IyZDI0K4rU=; b=WI9aVGwm7YTWXAmUw7I2TkGL7 +3yNEppGPH7QWQJPxzileVld9tlJ18/mLs6Bl25ozl+v4BIjsA218S0lYCUCswRLLufiAc0B6rkK5 oUKidiL8Srw8ncQhZw6r23fFR03KioL8SfO8L4hjp4sKjb/dIMBvqtZtk/YvVDRYjIzH/VrhC/31E Itpqly77Ro5XbRMTbqMcdp8JmL3QldO46NXdYPT2F1BNtXE4wEf+f+TG0WrMiFx/Eoo/vSq6zoNSb lMMvh6C7OESSWGH4E5E+kSuTlMw4BQQIC9URq4yg8uya8K+TjEceqR66PyikrL2h5t2puUHRuWPke MP07ddn6w==; Received: from [31.161.223.134] (helo=worktop.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.2 #3 (Red Hat Linux)) id 1iHti8-0004La-AY; Tue, 08 Oct 2019 17:55:50 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 2721E9802E0; Tue, 8 Oct 2019 19:55:37 +0200 (CEST) Date: Tue, 8 Oct 2019 19:55:37 +0200 From: Peter Zijlstra To: Vincent Guittot Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, pauld@redhat.com, valentin.schneider@arm.com, srikar@linux.vnet.ibm.com, quentin.perret@arm.com, dietmar.eggemann@arm.com, Morten.Rasmussen@arm.com, hdanton@sina.com Subject: Re: [PATCH v3 04/10] sched/fair: rework load_balance Message-ID: <20191008175537.GC22902@worktop.programming.kicks-ass.net> References: <1568878421-12301-1-git-send-email-vincent.guittot@linaro.org> <1568878421-12301-5-git-send-email-vincent.guittot@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1568878421-12301-5-git-send-email-vincent.guittot@linaro.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 19, 2019 at 09:33:35AM +0200, Vincent Guittot wrote: > + if (busiest->group_type == group_asym_packing) { > + /* > + * In case of asym capacity, we will try to migrate all load to > + * the preferred CPU. > + */ > + env->balance_type = migrate_load; > env->imbalance = busiest->group_load; > return; > } I was a bit surprised with this; I sorta expected a migrate_task,1 here. The asym_packing thing has always been a nr_running issue to me. If there is something to run, we should run on as many siblings/cores as possible, but preferably the 'highest' ranked siblings/cores.