Daniel Hahler, thank you for reporting this and helping make Ubuntu better. Could you please test the latest upstream kernel available from the very top line at the top of the page from http://kernel.ubuntu.com /~kernel-ppa/mainline/?C=N;O=D (the release names are irrelevant for testing, and please do not test the daily folder)? Install instructions are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds . This will allow additional upstream developers to examine the issue.
If the latest kernel did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this issue is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description: kernel-fixed-upstream kernel-fixed-upstream-X.Y-rcZ Where X, Y, and Z are numbers corresponding to the kernel version. If the mainline kernel does not fix the issue, please add the following tags: kernel-bug-exists-upstream kernel-bug-exists-upstream-X.Y-rcZ Please note, an error to install the kernel does not fit the criteria of kernel-bug-exists-upstream. Once testing of the latest upstream kernel is complete, please mark this report's Status as Confirmed. Please let us know your results. Thank you for your understanding. ** Tags added: latest-bios-1.40 ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1497520 Title: Slow performance after resuming from/on battery (CPUs do not scale above 800MHz) Status in linux package in Ubuntu: Incomplete Bug description: I have noticed slow performance after resuming from STR on battery. I can not trigger this always, but it seems to be related to suspending and resuming while on battery. The CPU scaling governors look like this then: % cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor powersave performance performance performance % cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_driver intel_pstate intel_pstate intel_pstate intel_pstate % cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq 3200000 3200000 3200000 3200000 When watching the current CPU frequencies, it can be seen that they don't go above 800000 ('watch grep \"cpu MHz\" /proc/cpuinfo'). I cannot see why they are limited to 800000. It looks like https://bugzilla.kernel.org/show_bug.cgi?id=61241, but /sys/devices/system/cpu/intel_pstate/max_perf_pct is at 100. Just writing the same setting for cpu0 again fixes it, and all CPUs will be scaled above 800MHz again: % echo powersave | sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: linux-image-3.19.0-28-generic 3.19.0-28.30 ProcVersionSignature: Ubuntu 3.19.0-28.30-generic 3.19.8-ckt5 Uname: Linux 3.19.0-28-generic x86_64 ApportVersion: 2.17.2-0ubuntu1.4 Architecture: amd64 CurrentDesktop: Unity Date: Sat Sep 19 10:39:02 2015 HibernationDevice: RESUME=UUID=d39463f5-889e-42ba-a729-f3f442f0c8dd InstallationDate: Installed on 2012-05-28 (1208 days ago) InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425) MachineType: LENOVO 42992PG ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.19.0-28-generic root=/dev/mapper/vg0-rootlv ro quiet splash RelatedPackageVersions: linux-restricted-modules-3.19.0-28-generic N/A linux-backports-modules-3.19.0-28-generic N/A linux-firmware 1.143.3 SourcePackage: linux UpgradeStatus: Upgraded to vivid on 2015-05-14 (127 days ago) dmi.bios.date: 05/14/2015 dmi.bios.vendor: LENOVO dmi.bios.version: 8DET70WW (1.40 ) dmi.board.asset.tag: Not Available dmi.board.name: 42992PG dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr8DET70WW(1.40):bd05/14/2015:svnLENOVO:pn42992PG:pvrThinkPadX220Tablet:rvnLENOVO:rn42992PG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 42992PG dmi.product.version: ThinkPad X220 Tablet dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1497520/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp