Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752090AbcC3LF0 (ORCPT ); Wed, 30 Mar 2016 07:05:26 -0400 Received: from mail-lb0-f170.google.com ([209.85.217.170]:36340 "EHLO mail-lb0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751837AbcC3LFZ convert rfc822-to-8bit (ORCPT ); Wed, 30 Mar 2016 07:05:25 -0400 MIME-Version: 1.0 In-Reply-To: References: <4187911.uaFVupaTVL@vostro.rjw.lan> Date: Wed, 30 Mar 2016 13:05:22 +0200 X-Google-Sender-Auth: YiXD7PYMkAE03hcLjJiJV-41XSQ Message-ID: Subject: Re: [intel-pstate driver regression] processor frequency very high even if in idle From: "Rafael J. Wysocki" To: =?UTF-8?Q?J=C3=B6rg_Otte?= Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Linux PM list Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2314 Lines: 56 On Wed, Mar 30, 2016 at 12:17 PM, Jörg Otte wrote: > 2016-03-29 23:34 GMT+02:00 Rafael J. Wysocki : >> On Tuesday, March 29, 2016 07:32:27 PM Jörg Otte wrote: >>> 2016-03-29 19:24 GMT+02:00 Jörg Otte : >>> > in v4.5 and earlier intel-pstate downscaled idle processors (load >>> > 0.1-0.2%) to minumum frequency, in my case 800MHz. >>> > >>> > Now in v4.6-rc1 the characteristic has dramatically changed. If in >>> > idle the processor frequency is more or less a few MHz around 2500Mhz. >>> > This is the maximum non turbo frequency. >>> > >>> > No difference between powersafe or performance governor. >>> > >>> > I currently use acpi_cpufreq which works as usual. >>> > >>> > Processor: >>> > Intel(R) Core(TM) i5-4200M CPU @ 2.50GHz (family: 0x6, model: 0x3c, >>> > stepping: 0x3) >>> > >>> > Last known good kernel is: 4.5.0-01127-g9256d5a >>> > First known bad kernel is: 4.5.0-02535-g09fd671 >>> > >>> > There is >>> > commit 277edba Merge tag 'pm+acpi-4.6-rc1-1' of >>> > git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm >>> > in between, which brought a few changes in intel_pstate. >> >> Can you please check commit a4675fbc4a7a (cpufreq: intel_pstate: Replace timers >> with utilization update callbacks)? >> > Yes , this solved the problem for me. > I had to resolve some conflicts myself when reverting that > commit. Hard work :). Thanks for doing this. Can you please post the revert patch you have used? > Here is a 10-seconds trace of the used frequencies when > in "desktop-idle": > > driver cpu0 cpu1 cpu2 cpu3 > ------------------------------------- > intel_pstate ( 800 928 941 1200) MHz load:( 0.2)% > intel_pstate ( 800 928 1181 1800) MHz load:( 0.0)% > intel_pstate ( 1675 1576 1347 800) MHz load:( 0.0)% > intel_pstate ( 1198 1576 842 800) MHz load:( 0.5)% > intel_pstate ( 800 1181 1113 1600) MHz load:( 0.0)% > intel_pstate ( 808 1181 805 800) MHz load:( 0.5)% > intel_pstate ( 844 1191 900 1082) MHz load:( 0.3)% > intel_pstate ( 816 1191 800 800) MHz load:( 0.0)% > intel_pstate ( 800 905 892 1082) MHz load:( 0.2)% > intel_pstate ( 945 905 1340 800) MHz load:( 0.3)% Please also run turbostat with and without your revert patch applied. Thanks, Rafael