Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030293AbcJTOcN (ORCPT ); Thu, 20 Oct 2016 10:32:13 -0400 Received: from mail-yb0-f175.google.com ([209.85.213.175]:34100 "EHLO mail-yb0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751827AbcJTOcM (ORCPT ); Thu, 20 Oct 2016 10:32:12 -0400 MIME-Version: 1.0 In-Reply-To: <2676989.xnUCnaPvEA@vostro.rjw.lan> References: <2198826.9suuMCzPZN@vostro.rjw.lan> <2676989.xnUCnaPvEA@vostro.rjw.lan> From: =?UTF-8?Q?J=C3=B6rg_Otte?= Date: Thu, 20 Oct 2016 16:32:10 +0200 Message-ID: Subject: Re: [4.9-rc1] Build-time 2x slower To: "Rafael J. Wysocki" Cc: Linus Torvalds , "Rafael J. Wysocki" , Michal Marek , Sedat Dilek , Ming Lei , LKML Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id u9KEWIYf026532 Content-Length: 2627 Lines: 63 2016-10-20 13:14 GMT+02:00 Rafael J. Wysocki : > On Thursday, October 20, 2016 09:57:45 AM Jörg Otte wrote: >> 2016-10-19 22:55 GMT+02:00 Rafael J. Wysocki : >> > On Wednesday, October 19, 2016 06:59:35 PM Jörg Otte wrote: >> >> 2016-10-19 17:29 GMT+02:00 Linus Torvalds : >> >> > On Wed, Oct 19, 2016 at 4:07 AM, Jörg Otte wrote: >> >> >> >> >> >> Additional info: I usally use schedutil governor. >> >> >> If I switch to performance governor problems go away. >> >> >> Maybe a cpufreq problem? >> >> > >> >> > Oh, I completely misread the original bug report, and then didn't read >> >> > your confirmation email right. >> >> > >> >> > I thought you had a slower build of the different kernels (when >> >> > building on the same kernel), and that the _build_ itself had slowed >> >> > down for some reason. But you're actually saying that doing the _same_ >> >> > build actually takes longer when running on 4.9-rc1. >> >> >> >> Exactly! >> >> >> >> Btw: ondemand governor is also good. >> >> >> >> > There are a few small cpufreq changes there in between commit >> >> > 29fbff8698fc (that you reported was fine - please tell me I got _that_ >> >> > right, at least?) and 4.9-rc1. >> >> >> >> Perfect! That's what I mean. >> >> >> >> > Adding Rafael to the cc. >> >> > >> >> > That said, none of them look all that likely to me. It *would* be good >> >> > if you could bisect it a bit (perhaps not fully, but a couple of >> >> > bisection steps to narrow down what area it is). >> >> >> >> I try that tomorrow. >> > >> > Well, please try commit ef98988ba369 (Merge tag 'pm-extra-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm) which is the >> > merge introducing the late cpufreq changes. If the issue is there, please >> > try to revert commit 899bb6642f2a (cpufreq: skip invalid entries when searching >> > the frequency) which is the only cpufreq one that may matter for the schedutil >> > governor (and I have one fix for that commit queued up already). >> > >> >> I first tried the merge but git said I'm already uptodate (my tree >> is at 1a1891d Merge tag 'for-f2fs-4.9-rc2' of >> git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs already) >> >> Then I did the revert of 899bb6642f2a and >> that worked fine for me. > > OK, thanks! > > Pointer arithmetics is messed up in that commit somewhat which may be the > reason for what you see. > > Please check if this patch helps (instead of the revert): > > https://patchwork.kernel.org/patch/9379639/ > Yes, works well for me. Thanks, Jörg