Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752034AbdG1NeW (ORCPT ); Fri, 28 Jul 2017 09:34:22 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:58668 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751673AbdG1NeV (ORCPT ); Fri, 28 Jul 2017 09:34:21 -0400 Subject: Re: [PATCH V6] sched/fair: Remove group imbalance from calculate_imbalance() To: Peter Zijlstra Cc: Jeffrey Hugo , Ingo Molnar , linux-kernel@vger.kernel.org, Austin Christ , Tyler Baicar , Timur Tabi References: <1499975708-31090-1-git-send-email-jhugo@codeaurora.org> <0f91065c-94cb-3780-0d77-f2be682086bf@arm.com> <20170726145407.rfswqxoclvezukwq@hirez.programming.kicks-ass.net> <5ddf061e-26a2-7151-adff-7ae339c848ac@arm.com> <20170728125924.eaw6unxude2qiyym@hirez.programming.kicks-ass.net> From: Dietmar Eggemann Message-ID: <634c755a-8a6c-c90a-21c1-6562becc11be@arm.com> Date: Fri, 28 Jul 2017 14:34:19 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20170728125924.eaw6unxude2qiyym@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 636 Lines: 19 On 28/07/17 13:59, Peter Zijlstra wrote: > On Fri, Jul 28, 2017 at 01:16:24PM +0100, Dietmar Eggemann wrote: >>>> IIRC the topology you had in mind was MC + DIE level with n (n > 2) DIE >>>> level sched groups. [...] >>> If I then start a 3rd loop, I see 100% 50%,50%. I then kill the 100%. >>> Then instantly they balance and I get 2x100% back. >> >> Yeah, could reproduce on IVB-EP (2x10x2). > > OK, I have one of those. What should I do, because I didn't actually see > anything odd. Me neither. Sorry, I was unclear. I meant I could reproduce your example, that one of the 50% task moves to the idle cpu on this machine. [...]