This is what I get right after boot and login into Unity 7 (executed in Gnome Terminal): $ ps aux | grep kworker | wc -l 1004
Kernel is 4.8.0-22-generic. After a few minutes, only 21 kworkers remain. Load after 4 minutes is not excessive (1244 sleeping processes), forgot to check load right after boot: up 4 min, 1 user, load average: 1,01, 1,79, 0,94 I'm not sure if it is of any help, but I've attached the output of "ps aux | grep kworker". ** Attachment added: "ps aux | grep kworker" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1626436/+attachment/4763631/+files/kworkers -- 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/1626436 Title: [4.8 regression] boot has become very slow Status in linux package in Ubuntu: Triaged Bug description: With yakkety's recent update from linux 4.4 to 4.8 booting has become a lot slower. It's not one service in particular, but without "quiet" and "splash" you can now easily read every single line instead of that whole wall of text zipping by. It now takes over 20s instead of ~10 seconds to boot. This is even more dramatic when factoring out the recent boot hang of NetworkManager (bug 1622893) and disabling lightdm: sudo systemctl mask NetworkManager NetworkManager-wait-online lightdm then booting with 4.4 takes 1.5s and with 4.8 19.5s (!). Some excerps from systemd-analyze blame: 4.4: 474ms postfix@-.service 395ms lxd-containers.service 305ms networking.service 4.8: 4.578s postfix@-.service 7.300s lxd-containers.service 6.285s networking.service I attach the full outputs of critical-chain and analyze for 4.4 and 4.8 for reference. This is much less noticeable in the running system. There is no immediate feeling of sluggishness (although my system is by and large idle). I compared the time of sbuilding colord under similar circumstances (-j4, building on tmpfs, thus no hard disk delays; running with fully pre-loaded apt-cacher-ng thus no random network delays), and with 4.4 it takes 6.5 minutes and with 4.8 it takes 7.5. So that got a bit slower, but much less dramatically than during boot, so this is either happening when a lot of processes run in parallel, or is perhaps related to setting up cgroups. One thing I noticed that during sbuild in 4.8 "top" shows ridiculous loads (~ 250) under 4.8, while it's around 4 or 5 under 4.8. But that doesn't reflect in actual sluggishness, so this might be just an unrelated bug. ProblemType: Bug DistroRelease: Ubuntu 16.10 Package: linux-image-4.8.0-11-generic 4.8.0-11.12 ProcVersionSignature: Ubuntu 4.8.0-11.12-generic 4.8.0-rc6 Uname: Linux 4.8.0-11-generic x86_64 ApportVersion: 2.20.3-0ubuntu7 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/pcmC0D0c: martin 3049 F...m pulseaudio /dev/snd/pcmC0D0p: martin 3049 F...m pulseaudio /dev/snd/controlC0: martin 3049 F.... pulseaudio Date: Thu Sep 22 09:42:56 2016 EcryptfsInUse: Yes MachineType: LENOVO 2324CTO ProcEnviron: TERM=linux PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=de_DE.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/@/boot/vmlinuz-4.8.0-11-generic.efi.signed root=UUID=f86539b0-3a1b-4372-83b0-acdd029ade68 ro rootflags=subvol=@ systemd.debug-shell RelatedPackageVersions: linux-restricted-modules-4.8.0-11-generic N/A linux-backports-modules-4.8.0-11-generic N/A linux-firmware 1.161 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/09/2013 dmi.bios.vendor: LENOVO dmi.bios.version: G2ET95WW (2.55 ) dmi.board.asset.tag: Not Available dmi.board.name: 2324CTO dmi.board.vendor: LENOVO dmi.board.version: 0B98401 Pro dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvrG2ET95WW(2.55):bd07/09/2013:svnLENOVO:pn2324CTO:pvrThinkPadX230:rvnLENOVO:rn2324CTO:rvr0B98401Pro:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 2324CTO dmi.product.version: ThinkPad X230 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1626436/+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
