Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757952AbZADMFx (ORCPT ); Sun, 4 Jan 2009 07:05:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750877AbZADMFp (ORCPT ); Sun, 4 Jan 2009 07:05:45 -0500 Received: from mail.gmx.net ([213.165.64.20]:41321 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750795AbZADMFo (ORCPT ); Sun, 4 Jan 2009 07:05:44 -0500 X-Authenticated: #5108953 X-Provags-ID: V01U2FsdGVkX1+Syv4fuACSGogYhYndp3AYjd743qsh3NhN8AtI2i MBDEMiuiqiqeX6 From: Toralf =?iso-8859-15?q?F=F6rster?= To: linux-kernel@vger.kernel.org Subject: 2.6.27.10: CPU ondemand governor doesn't work well Date: Sun, 4 Jan 2009 13:05:34 +0100 User-Agent: KMail/1.9.10 Cc: cpufreq@vger.kernel.org MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart30042847.jyrcqDUBTU"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200901041305.39883.toralf.foerster@gmx.de> X-Y-GMX-Trusted: 0 X-FuHaFi: 0.46 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2670 Lines: 91 --nextPart30042847.jyrcqDUBTU Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Starting with kernel 2.6.27.10 I observed sometimes that my ThinkPad T41 st= ays=20 at CPU frequency of 600 MHz when I run a lot of processes with nice level 3= =20 and few more at 19 - even if I have some foreground jobs which normally for= ce=20 the CPU to go to at 1700 MHz=20 A typical scenario is to compile glibc at a Gentoo system mit "make -j 2" a= nd=20 then run another make job at nice level 0 or try to start firefox (which=20 start time itself is OTOH slow enough even with 1.7 GHz). I can quantify th= is=20 observation with a quick&dirty command line like : $> time factor 819734028463158891 I would expect a real value of 6-7 seconds and a user value of 5-6 seconds.= =20 However when I used it 2 times in a row I got : tfoerste@n22 ~ $ time factor 819734028463158891 819734028463158891: 3 273244676154386297 real 0m51.658s user 0m15.691s sys 0m0.013s tfoerste@n22 ~ $ time factor 819734028463158891 819734028463158891: 3 273244676154386297 real 0m19.136s user 0m6.944s sys 0m0.044s BTW during startup I set : $>echo 1 > /sys/devices/system/cpu/cpu0/cpufreq/ondemand/ignore_nice_load My system: tfoerste@n22 ~ $ uname -a Linux n22 2.6.27-gentoo-r7 #12 Sun Dec 28 18:26:57 CET 2008 i686 Intel(R)=20 Pentium(R) M processor 1700MHz GenuineIntel GNU/Linux The appropriate kernel config values are : tfoerste@n22 ~/devel/wireshark/docbook $ zgrep -e GOV -e=20 =46REQ /proc/config.gz | grep -v '#' CONFIG_CPU_FREQ=3Dy CONFIG_CPU_FREQ_TABLE=3Dy CONFIG_CPU_FREQ_STAT=3Dm CONFIG_CPU_FREQ_STAT_DETAILS=3Dy CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=3Dy CONFIG_CPU_FREQ_GOV_PERFORMANCE=3Dy CONFIG_CPU_FREQ_GOV_POWERSAVE=3Dm CONFIG_CPU_FREQ_GOV_ONDEMAND=3Dy CONFIG_X86_ACPI_CPUFREQ=3Dm CONFIG_CPU_IDLE_GOV_LADDER=3Dy CONFIG_CPU_IDLE_GOV_MENU=3Dy =2D-=20 MfG/Sincerely Toralf F=F6rster pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3 --nextPart30042847.jyrcqDUBTU Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) iEYEABECAAYFAklgphMACgkQhyrlCH22naNCOQCghZC8IAsAcus6HWpSn/hk8Vyv giAAnivBBFuU5M7urxF8/2gQ52Kwbhek =8Sma -----END PGP SIGNATURE----- --nextPart30042847.jyrcqDUBTU-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/