> did you confirm that the quoted commit does indeed fix your issue? No, I am not building Linux from source currently, and have not tried e.g. applying that patch/commit to the Ubuntu package.
I am now back using the Ubuntu kernel, since the workaround is trivial in case it is required - once you know what the issue is about. -- 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) with intel_pstate 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
