Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754196AbdIGHbm (ORCPT ); Thu, 7 Sep 2017 03:31:42 -0400 Received: from mail-wr0-f182.google.com ([209.85.128.182]:36119 "EHLO mail-wr0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752315AbdIGHbl (ORCPT ); Thu, 7 Sep 2017 03:31:41 -0400 X-Google-Smtp-Source: ADKCNb5ngoK4lnX2XuakV5Ul6wa5tRmo7rIVJ7FzpSOMVpKwDmlo8oaDJoXDboy3+jbp+qoOZitUcg== Date: Thu, 7 Sep 2017 09:31:37 +0200 From: Ingo Molnar To: Mike Galbraith Cc: Peter Zijlstra , Andy Lutomirski , Andy Lutomirski , "linux-kernel@vger.kernel.org" Subject: Re: Abysmal scheduler performance in Linus' tree? Message-ID: <20170907073137.yyht5pqbpshpyiwl@gmail.com> References: <20170906082520.xgvo3hewje7jvdyo@hirez.programming.kicks-ass.net> <877A43A3-AC8F-4D7C-88E4-8E3D36B1DAFA@amacapital.net> <20170906090333.7v627vdyvhe3x2cs@hirez.programming.kicks-ass.net> <20170906161422.kvqe5y6b3ng6ouyu@hirez.programming.kicks-ass.net> <1504764929.6355.5.camel@gmx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1504764929.6355.5.camel@gmx.de> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 998 Lines: 29 * Mike Galbraith wrote: > On Wed, 2017-09-06 at 18:14 +0200, Peter Zijlstra wrote: > > On Wed, Sep 06, 2017 at 11:03:33AM +0200, Peter Zijlstra wrote: > > > On Wed, Sep 06, 2017 at 01:59:14AM -0700, Andy Lutomirski wrote: > > > > > Any specifics on your setup? > > > > > > > > On further fiddling, I only see this after a suspend and resume cycle. > > > > > > Ah, ok. That's not something I otherwise test. Lets see if I can force > > > this brick of mine through a suspend-resume cycle :-) > > > > I'd be suspicious of these here commits: > > > > 77d1dfda0e79 ("sched/topology, cpuset: Avoid spurious/wrong domain rebuilds") > > Seems to be that one. ?After suspend/resume, cpu7 (i4790+SMT) is online > with NULL domain. ?offline/online it, it grows proper domains. Thanks, that's really useful, should narrow things down! > (on vacation, about to go explore that unfamiliar 'outside' place) ? Be careful, it's a dangerous world for kernel hackers! ;-) Thanks, Ingo