Public bug reported: I've installed fresh 9.10 and I'm with the defaults. This is how I've noticed the following behaviour and I want to share it.
As I have two cores - I've setup two cpufreq scaling monitors applets. By default my idle system is working on 1.00Ghz on both CPUs (cores to be precise). In one console I do: while :; do echo -n "" ; done htop shows that CPU1 goes 100% and CPU1 scaling monitor shows that CPU1 goes 1.8Ghz (max) right away. So I open another console and do: while :; do echo -n "" ; done but CPU0 goes 100% but CPU0 scalling monitor show that CPU0 is only at 1.33Ghz and this is not changing through time. Now comes the funny part. I press the Ctrl+c in one of the consoles and now both CPUs go 1.00Ghz while CPU0 is working 100% and the other almost idle ! I've recreated this behaviour few times (100% reproduction rate). This behaviour is not visible when both CPUs use i.e. conservative cpufreq. I have no idea behind the logic ondeman cpufreq gov. is being driven, but for me ubuntu always had a problems with it. The other thing is this - when watching the following in HD: http://www.youtube.com/watch?v=zlfKdbWwruY I'm unable to get any CPU to work on 1.8Ghz and the movie is skipping frequently due to underperformed decoding / display. So I've played around and changed cpu?/cpufreq/ondemand/up_threshold from default 95 to 30 . Now everything is perfectly fine. The original funny behaviour is gone. I think that 95 is way to high for default. I want my CPU to work on high speed if required and slow down if there's nothing to do. (as per http://www.lesswatts.org/projects/applications-power-management/race-to- idle.php ) Maybe 5% margin is not enough to catch quickly that the there's a CPU shortage here and there. I'm not sure, but someone with more time and knowledge should take a look at this. ProblemType: Bug Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: dpc 1723 F.... pulseaudio /dev/snd/pcmC0D0p: dpc 1723 F...m pulseaudio CRDA: Error: [Errno 2] No such file or directory Card0.Amixer.info: Card hw:0 'Intel'/'HDA Intel at 0xf1200000 irq 22' Mixer name : 'Realtek ALC883' Components : 'HDA:10ec0883,15580721,00100002 HDA:10573055,10573055,00100700' Controls : 28 Simple ctrls : 17 Date: Thu Nov 5 19:21:02 2009 DistroRelease: Ubuntu 9.10 HibernationDevice: RESUME=UUID=32932d31-e3e8-4410-825a-26f418ee7240 InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027) MachineType: ARISTO Slim 1250 Package: linux-image-2.6.31-14-generic 2.6.31-14.48 ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.31-14-generic root=UUID=95827051-2f3b-467f-9f8a-d99370280630 ro quiet splash ProcEnviron: LANG=en_US.UTF-8 SHELL=/bin/bash ProcVersionSignature: Ubuntu 2.6.31-14.48-generic RelatedPackageVersions: linux-backports-modules-2.6.31-14-generic N/A linux-firmware 1.24 RfKill: 0: phy0: Wireless LAN Soft blocked: no Hard blocked: no SourcePackage: linux Uname: Linux 2.6.31-14-generic x86_64 dmi.bios.date: 01/10/2008 dmi.bios.vendor: Phoenix Technologies LTD dmi.bios.version: SROSA001.86C.0038.D.080110 dmi.board.name: Slim 1250 dmi.board.vendor: ARISTO dmi.board.version: Not Applicable dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 1 dmi.chassis.vendor: ARISTO dmi.chassis.version: N/A dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvrSROSA001.86C.0038.D.080110:bd01/10/2008:svnARISTO:pnSlim1250:pvrNotApplicable:rvnARISTO:rnSlim1250:rvrNotApplicable:cvnARISTO:ct1:cvrN/A: dmi.product.name: Slim 1250 dmi.product.version: Not Applicable dmi.sys.vendor: ARISTO ** Affects: ubuntu Importance: Undecided Status: New ** Tags: amd64 apport-bug -- ondemand cpufreq governor broken on core 2 duo cpu https://bugs.launchpad.net/bugs/475706 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs