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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 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 F3718C432C0 for ; Tue, 26 Nov 2019 15:14:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF5B820722 for ; Tue, 26 Nov 2019 15:14:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728359AbfKZPOU (ORCPT ); Tue, 26 Nov 2019 10:14:20 -0500 Received: from mx2.suse.de ([195.135.220.15]:58184 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728078AbfKZPOU (ORCPT ); Tue, 26 Nov 2019 10:14:20 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 1E196B9ED; Tue, 26 Nov 2019 15:14:18 +0000 (UTC) Message-ID: <1574781600.7677.2.camel@suse.cz> Subject: Re: [PATCH v4 1/6] x86,sched: Add support for frequency invariance From: Giovanni Gherdovich To: Doug Smythies , 'Srinivas Pandruvada' , 'Thomas Gleixner' , 'Ingo Molnar' , 'Peter Zijlstra' , 'Borislav Petkov' , 'Len Brown' , "'Rafael J . Wysocki'" Cc: x86@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, 'Mel Gorman' , 'Matt Fleming' , 'Viresh Kumar' , 'Juri Lelli' , 'Paul Turner' , 'Vincent Guittot' , 'Quentin Perret' , 'Dietmar Eggemann' Date: Tue, 26 Nov 2019 16:20:00 +0100 In-Reply-To: <000801d5a41e$a7fce2c0$f7f6a840$@net> References: <20191113124654.18122-1-ggherdovich@suse.cz> <20191113124654.18122-2-ggherdovich@suse.cz> <000001d5a29b$c944fd70$5bcef850$@net> <1574697961.16378.5.camel@suse.cz> <000801d5a41e$a7fce2c0$f7f6a840$@net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Mon, 2019-11-25 at 21:59 -0800, Doug Smythies wrote: > [...] > The issue with the schedutil governor not working properly in the 5.4 RC series > appears to be hardware dependant. > > My test computer is Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz., Sandy Bridge. > On a temporary basis, I acquired a computer with an > Intel(R) Core(TM) i5-4460 CPU @ 3.20GHz, Haswell, > and schedutil governor behaviour with the exact same kernels is fine: > > That "gitsource" test, "make test" 6 times, first run thrown out: > > Kernel 5.4 intel_cpufreq/schedutil: 3411.8 seconds > Kernel 5.4 + gg 6 intel_cpufreq/schedutil: 1696.7 seconds > Ratio: 0.49 > Recall you got a ratio of 0.49 with 5th generation, Broadwell. It's good to hear that we're getting the same performance numbers for this patchset on all hardware that is not a Sandy Bridge. Thanks for double checking, independent verification is always valuable. Now, regarding the 5.4 regression for schedutil you see on Sandy Bridge: can we move this to the kernel bugzilla? Would you care to open a bug there and CC me to it? If it's reproducible we should assess it and see what can be done. I've tried gitsource on 5.3 versus 5.4, using intel_cpufreq + schedutil; I don't see the drop you're observing, but I don't have a Sandy Bridge readily available. This is what I see: Arithmetic mean of elapsed time for gitsource over 5 iterations (seconds): microarch v5.3 (baseline) v5.4 ------------------------------------------------------------------ Haswell 1337.84 +- 0.11% 1336.35 +- 0.12% ( 0.11%) Broadwell 1335.42 +- 0.08% 1352.54 +- 0.03% ( -1.28%) Skylake 887.03 +- 1.02% 870.90 +- 1.19% ( 1.82%) I'm looking around for a Sandy Bridge but I can make no promises at the moment. Thanks, Giovanni