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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=ham 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 C2359C433DB for ; Fri, 5 Feb 2021 07:07:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 806F364FB7 for ; Fri, 5 Feb 2021 07:07:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231314AbhBEHHN (ORCPT ); Fri, 5 Feb 2021 02:07:13 -0500 Received: from mx2.suse.de ([195.135.220.15]:41348 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231230AbhBEHHI (ORCPT ); Fri, 5 Feb 2021 02:07:08 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 48858B038; Fri, 5 Feb 2021 07:06:26 +0000 (UTC) Message-ID: <1612508785.19825.6.camel@suse.cz> Subject: Re: [PATCH v1 1/2] cpufreq: ACPI: Extend frequency tables to cover boost frequencies From: Giovanni Gherdovich To: "Rafael J. Wysocki" , Linux PM Cc: LKML , Linux ACPI , Peter Zijlstra , Srinivas Pandruvada , Viresh Kumar , Mel Gorman , Michael Larabel , Juri Lelli , Vincent Guittot Date: Fri, 05 Feb 2021 08:06:25 +0100 In-Reply-To: <8467867.3EdU9UaQ17@kreacher> References: <13690581.X0sz4iL7V8@kreacher> <8467867.3EdU9UaQ17@kreacher> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2021-02-04 at 18:25 +0100, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > A severe performance regression on AMD EPYC processors when using > the schedutil scaling governor was discovered by Phoronix.com and > attributed to the following commits: > > 41ea667227ba ("x86, sched: Calculate frequency invariance for > AMD systems") > > 976df7e5730e ("x86, sched: Use midpoint of max_boost and max_P > for frequency invariance on AMD EPYC") > > [snip] > > Fixes: 41ea667227ba ("x86, sched: Calculate frequency invariance for AMD systems") > Fixes: 976df7e5730e ("x86, sched: Use midpoint of max_boost and max_P for frequency invariance on AMD EPYC") > Fixes: db865272d9c4 ("cpufreq: Avoid configuring old governors as default with intel_pstate") > Link: https://www.phoronix.com/scan.php?page=article&item=linux511-amd-schedutil&num=1 > Link: https://lore.kernel.org/linux-pm/20210203135321.12253-2-ggherdovich@suse.cz/ > Reported-by: Michael Larabel > Diagnosed-by: Giovanni Gherdovich > Signed-off-by: Rafael J. Wysocki > --- > drivers/cpufreq/acpi-cpufreq.c | 107 ++++++++++++++++++++++++++++++++++++----- > 1 file changed, 95 insertions(+), 12 deletions(-) > > Index: linux-pm/drivers/cpufreq/acpi-cpufreq.c > =================================================================== > --- linux-pm.orig/drivers/cpufreq/acpi-cpufreq.c > +++ linux-pm/drivers/cpufreq/acpi-cpufreq.c > [...] Tested-by: Giovanni Gherdovich Reviewed-by: Giovanni Gherdovich Note there is also the Tested-by: Michael, from the other thread https://lore.kernel.org/lkml/5ea06dbe-255c-3d22-b9bd-6e627c5f94af@phoronix.com/ I tested this patch with the "NASA Parallel Benchmarks" from [link below], the results confirms that the 5.10 performance is recovered: Ratios of completion times, lower is better (5.10 is the baseline) 5.10 5.11-rc6 5.11-rc6-ggherdov 5.11-rc6-rafael ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Integer Sort 1.00 1.21 0.91 0.93 Embarrassingly Parallel 1.00 1.60 1.00 1.00 Discrete FFT 1.00 1.68 0.67 0.67 CPU : MODEL : 2x AMD EPYC 7742 FREQUENCY TABLE : P2: 1.50 GHz P1: 2.00 GHz P0: 2.25 GHz MAX BOOST : 3.40 GHz [link] https://www.nas.nasa.gov/publications/npb.html Thanks, Giovanni