Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.15 kernel[0].
If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'. If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'. Once testing of the upstream kernel is complete, please mark this bug as "Confirmed". Thanks in advance. [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15-rc9 ** 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/1744543 Title: Screen updating with Compiz causes high-CPU kworker thread in 4.13 or earlier Status in linux package in Ubuntu: Incomplete Bug description: This duplicates the information in https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/1744515. Filing this to get more exposure. The automatically-included information for this reports notes that I'm using kernel 4.8, where this issue doesn't occur. I don't have any other kernels to test with. When the screen updates in 4.13 while running Compiz, it causes high CPU usage in a kworker thread. This was 30~40% of a CPU core on my system. This doesn't happen with other window managers tested, like Metacity, or whatever non-Compiz Gnome and Ubuntu use (gnome-shell maybe, though that 15% CPU load more than Metacity when I checked). Since Unity uses Compiz, it happens there as well as with 'Ubuntu flashback Compiz'. This seems unrelated to how much of the screen is being repainted, as the 'Show Repaint' plugin in Compiz can show that only a few pixels are being updated and the kworker load is the same. ProblemType: Bug DistroRelease: Ubuntu 17.10 Package: linux-generic 4.13.0.25.26 ProcVersionSignature: Ubuntu 4.8.0-34.36-generic 4.8.11 Uname: Linux 4.8.0-34-generic x86_64 ApportVersion: 2.20.7-0ubuntu3.7 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/pcmC0D0p: misaki 1685 F...m pulseaudio /dev/snd/controlC0: misaki 1685 F.... pulseaudio CurrentDesktop: GNOME-Flashback:GNOME Date: Sun Jan 21 00:17:16 2018 HibernationDevice: RESUME=UUID=ea8d7b22-9a3e-412e-af6a-8fc260a76a2c MachineType: ASUSTeK Computer Inc. N50Vn ProcFB: 0 nouveaufb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.8.0-34-generic root=UUID=b09dc720-93ec-4fdf-a42f-7ea19a9af555 ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.8.0-34-generic N/A linux-backports-modules-4.8.0-34-generic N/A linux-firmware 1.169.1 SourcePackage: linux UpgradeStatus: Upgraded to artful on 2018-01-09 (12 days ago) WpaSupplicantLog: dmi.bios.date: 03/05/2009 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 211 dmi.board.asset.tag: ATN12345678901234567 dmi.board.name: N50Vn dmi.board.vendor: ASUSTeK Computer Inc. dmi.board.version: 1.0 dmi.chassis.asset.tag: ATN12345678901234567 dmi.chassis.type: 10 dmi.chassis.vendor: ASUSTeK Computer Inc. dmi.chassis.version: 1.0 dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr211:bd03/05/2009:svnASUSTeKComputerInc.:pnN50Vn:pvr1.0:rvnASUSTeKComputerInc.:rnN50Vn:rvr1.0:cvnASUSTeKComputerInc.:ct10:cvr1.0: dmi.product.name: N50Vn dmi.product.version: 1.0 dmi.sys.vendor: ASUSTeK Computer Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1744543/+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
