Xcausing wakeups may coincide with enabled composing. On my Intel chipset graphics, this causes approx. an additional 50 wakeups per second. If composing is disabled, everything is back to normal. On another notebook with a Radeon 5470 (using fglrx), there was no such difference.
In addition, it also seems that X increases the load to rather large levels, despite being idle. With Ubuntu 10.10 (and kernel newer than 2.6.31) I have observed loads around 0.7, without anything showing up in top. 2010/11/4 Peter Sasi <524...@bugs.launchpad.net>: > > ** Attachment added: "powertop-dump-5min-2.6.36-020636-generic.txt" > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/524281/+attachment/1722665/+files/powertop-dump-5min-2.6.36-020636-generic.txt > > ** Also affects: xorg (Ubuntu) > Importance: Undecided > Status: New > > -- > Tens of wakes per second in "[kernel scheduler] Load balancing tick" on Core > 2 Duo even with only 1 core enabled > https://bugs.launchpad.net/bugs/524281 > You received this bug notification because you are a direct subscriber > of the bug. > > Status in “linux” package in Ubuntu: Triaged > Status in “xorg” package in Ubuntu: New > Status in Arch Linux: New > Status in “linux-2.6” package in Debian: Incomplete > > Bug description: > powertop reports many wakes per second (quantity depending on system) in > "[kernel scheduler] Load balancing tick" task, rising with little load, on > many kinds of multi-core (?) systems (original report was on a Core 2 Duo > processor (T6500) with a single core enabled (multicore disabled in BIOS)). > > Cause of the problem: > With kernel 2.6.32, there came a patch to the scheduler that introduced this > problem (that was backported to some other versions as well). Even though > this problem occurred first in Lucid, it is NOT specific to Lucid or Ubuntu > at all (Debian bug report at > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=521944, reproducable in Arch > Linux as well). Work is ongoing to get things straight in kernel, but it will > take a long time until this reaches Ubuntu (see > http://lkml.org/lkml/2010/7/6/172). > > Workarounds that DO NOT work (may improve situation but not solve it): > - maxcpus=1 > - noapic > - nosmp > - nolapic > - use mainline kernel > > Workarounds that DO (probably) work: > - tip version of kernel > (git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git, from > http://lkml.org/lkml/2010/7/8/75) > - use maverick's kernel with applied patches > (https://launchpad.net/~brian-rogers/+archive/power, from comment #80) > > ProblemType: Bug > AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.21. > Architecture: i386 > ArecordDevices: > **** List of CAPTURE Hardware Devices **** > card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog] > Subdevices: 1/1 > Subdevice #0: subdevice #0 > AudioDevicesInUse: > USER PID ACCESS COMMAND > /dev/snd/controlC0: etrusco 1606 F.... pulseaudio > etrusco 15151 F.... foobar2000.exe > CRDA: Error: [Errno 2] No such file or directory > Card0.Amixer.info: > Card hw:0 'Intel'/'HDA Intel at 0xfddf8000 irq 22' > Mixer name : 'Realtek ALC269' > Components : 'HDA:10ec0269,1b0a4009,00100004 > HDA:11c11040,1b0a4007,00100200' > Controls : 19 > Simple ctrls : 11 > Card1.Amixer.info: > Card hw:1 'HDMI'/'HDA ATI HDMI at 0xfebec000 irq 17' > Mixer name : 'ATI R6xx HDMI' > Components : 'HDA:1002aa01,00aa0100,00100100' > Controls : 4 > Simple ctrls : 1 > Card1.Amixer.values: > Simple mixer control 'IEC958',0 > Capabilities: pswitch pswitch-joined penum > Playback channels: Mono > Mono: Playback [on] > Date: Fri Feb 19 05:25:42 2010 > DistroRelease: Ubuntu 10.04 > EcryptfsInUse: Yes > MachineType: Philco PHN10XXX. > Package: linux-image-2.6.32-13-generic 2.6.32-13.18 > ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.32-13-generic > root=UUID=d482e94f-9370-4ad2-9536-986541003db5 ro acpi.power_nocheck=1 > acpi_osi=linux radeon.blacklist=yes > ProcEnviron: > LANG=en_US.UTF-8 > SHELL=/bin/bash > ProcVersionSignature: Ubuntu 2.6.32-13.18-generic > Regression: No > RelatedPackageVersions: linux-firmware 1.29 > Reproducible: Yes > RfKill: > 0: phy0: Wireless LAN > Soft blocked: no > Hard blocked: no > SourcePackage: linux > TestedUpstream: No > Uname: Linux 2.6.32-13-generic i686 > dmi.bios.date: 06/01/2009 > dmi.bios.vendor: American Megatrends Inc. > dmi.bios.version: 1.01 > dmi.board.asset.tag: To Be Filled By O.E.M. > dmi.board.vendor: PEGATRON CORP. > dmi.board.version: To be filled by O.E.M. > dmi.chassis.asset.tag: To Be Filled By O.E.M. > dmi.chassis.type: 10 > dmi.chassis.vendor: PEGATRON CORP. > dmi.chassis.version: To Be Filled By O.E.M. > dmi.modalias: > dmi:bvnAmericanMegatrendsInc.:bvr1.01:bd06/01/2009:svnPhilco:pnPHN10XXX.:pvr1.01:rvnPEGATRONCORP.:rn:rvrTobefilledbyO.E.M.:cvnPEGATRONCORP.:ct10:cvrToBeFilledByO.E.M.: > dmi.product.name: PHN10XXX. > dmi.product.version: 1.01 > dmi.sys.vendor: Philco > > > > To unsubscribe from this bug, go to: > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/524281/+subscribe > -- Tens of wakes per second in "[kernel scheduler] Load balancing tick" on Core 2 Duo even with only 1 core enabled https://bugs.launchpad.net/bugs/524281 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