I think this is a systemd/udevd kinda bug isn't it? ** Also affects: systemd (Ubuntu) Importance: Undecided Status: New
** Changed in: systemd (Ubuntu) Importance: Undecided => High -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1626651 Title: brightness keys are handled slower in Yakkety than Xenial Status in linux package in Ubuntu: Incomplete Status in systemd package in Ubuntu: New Bug description: I've noticed on Lenovo X220 and X230 laptops that pressing brightness keys on Yakkety seems less responsive and slower than Xenial. I ran forkstat on Xenial and just observed udev being forked off: Xenial: $ sudo forkstat Time Event PID Info Duration Process 17:37:35 fork 273 parent /lib/systemd/systemd-udevd 17:37:35 fork 1977 child /lib/systemd/systemd-udevd 17:37:35 exit 1977 0 0.008 /lib/systemd/systemd-udevd Whereas on Yakkety, there is far more activity: Time Event PID Info Duration Process 16:35:34 fork 2626 parent update-notifier 16:35:34 fork 2645 child update-notifier 16:35:34 exec 2645 /usr/bin/python3 /usr/share/apport/apport-checkreports 16:35:34 exit 2645 256 0.221 /usr/bin/python3 /usr/share/apport/apport-checkreports 16:35:34 fork 2626 parent update-notifier 16:35:34 fork 2646 child update-notifier 16:35:34 exec 2646 /usr/bin/python3 /usr/share/apport/apport-checkreports --system 16:35:34 exit 2646 256 0.188 /usr/bin/python3 /usr/share/apport/apport-checkreports --system 16:35:36 fork 1576 parent /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 fork 2647 child /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 exec 2647 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-max-brightness 16:35:36 exit 2647 0 0.008 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-max-brightness 16:35:36 fork 1576 parent /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 fork 2648 child /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 exec 2648 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-brightness 16:35:36 exit 2648 0 0.006 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-brightness 16:35:36 fork 1576 parent /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 fork 2649 child /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 exec 2649 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-brightness 16:35:36 exit 2649 0 0.007 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-brightness 16:35:36 fork 1576 parent /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 fork 2650 child /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 exec 2650 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-max-brightness 16:35:36 exit 2650 0 0.006 /usr/lib/unity-settings-daemon/usd-backlight-helper --get-max-brightness 16:35:36 fork 1576 parent /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 fork 2651 child /usr/lib/unity-settings-daemon/unity-settings-daemon 16:35:36 exec 2651 pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 clone 2651 parent pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 clone 2652 thread pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 clone 2651 parent pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 clone 2653 thread pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 fork 1 parent /sbin/init splash 16:35:36 fork 2654 child /sbin/init splash Time Event PID Info Duration Process 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2655 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2656 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2657 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2658 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2659 child /lib/systemd/systemd-udevd 16:35:36 exit 2659 0 0.005 /lib/systemd/systemd-udevd 16:35:36 exit 2658 0 0.006 /lib/systemd/systemd-udevd 16:35:36 exit 2657 0 0.007 /lib/systemd/systemd-udevd 16:35:36 exit 2656 0 0.008 /lib/systemd/systemd-udevd 16:35:36 exit 2655 0 0.008 /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2660 child /lib/systemd/systemd-udevd 16:35:36 exit 2660 0 0.001 /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2661 child /lib/systemd/systemd-udevd 16:35:36 exit 2661 0 0.002 /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2662 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2663 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2664 child /lib/systemd/systemd-udevd 16:35:36 fork 2654 parent /sbin/init splash 16:35:36 fork 2665 child (systemd) 16:35:36 exec 2654 /lib/systemd/systemd --user 16:35:36 exit 2662 0 0.010 /lib/systemd/systemd-udevd 16:35:36 exit 2664 0 0.007 /lib/systemd/systemd-udevd Time Event PID Info Duration Process 16:35:36 exit 2663 0 0.009 /lib/systemd/systemd-udevd 16:35:36 fork 2654 parent /lib/systemd/systemd --user 16:35:36 fork 2666 child /lib/systemd/systemd --user 16:35:36 exit 2666 0 0.001 /lib/systemd/systemd --user 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2667 child /lib/systemd/systemd-udevd 16:35:36 exit 2667 0 0.003 /lib/systemd/systemd-udevd 16:35:36 fork 2654 parent /lib/systemd/systemd --user 16:35:36 fork 2668 child /lib/systemd/systemd --user 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2669 child /lib/systemd/systemd-udevd 16:35:36 exit 2669 0 0.002 /lib/systemd/systemd-udevd 16:35:36 exec 2668 /bin/systemctl --user set-environment DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/0/bus 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2670 child /lib/systemd/systemd-udevd 16:35:36 exit 2670 0 0.001 /lib/systemd/systemd-udevd 16:35:36 exit 2668 0 0.009 /bin/systemctl --user set-environment DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/0/bus 16:35:36 fork 2 parent [kthreadd] 16:35:36 fork 2671 child [kworker/u16:4] 16:35:36 exec 2671 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service/dbus.socket] 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2672 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2673 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2674 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2675 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2676 child /lib/systemd/systemd-udevd 16:35:36 exit 2671 0 0.005 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service/dbus.socket] 16:35:36 fork 233 parent /lib/systemd/systemd-udevd Time Event PID Info Duration Process 16:35:36 fork 2677 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2678 child /lib/systemd/systemd-udevd 16:35:36 exit 2653 0 0.126 pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 exit 2652 0 0.126 pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 exec 2651 /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 exit 2673 0 0.013 /lib/systemd/systemd-udevd 16:35:36 exit 2672 0 0.013 /lib/systemd/systemd-udevd 16:35:36 exit 2678 0 0.011 /lib/systemd/systemd-udevd 16:35:36 exit 2675 0 0.013 /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2679 child /lib/systemd/systemd-udevd 16:35:36 exit 2674 0 0.020 /lib/systemd/systemd-udevd 16:35:36 exit 2651 0 0.146 /usr/lib/unity-settings-daemon/usd-backlight-helper --set-brightness 2250 16:35:36 fork 2 parent [kthreadd] 16:35:36 fork 2680 child [kworker/u16:5] 16:35:36 exec 2680 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/session-2.scope] 16:35:36 exit 2676 0 0.022 /lib/systemd/systemd-udevd 16:35:36 exit 2679 0 0.003 /lib/systemd/systemd-udevd 16:35:36 exit 2677 0 0.022 /lib/systemd/systemd-udevd 16:35:36 exit 2680 0 0.003 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/session-2.scope] 16:35:36 fork 2654 parent /lib/systemd/systemd --user 16:35:36 fork 2681 child /lib/systemd/systemd --user 16:35:36 exec 2681 /bin/kill -s 58 2654 16:35:36 exit 2681 0 0.200 /bin/kill -s 58 2654 16:35:36 fork 2 parent [kthreadd] 16:35:36 fork 2682 child [kworker/u16:5] 16:35:36 exec 2682 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service/systemd-exit.service] 16:35:36 exit 2654 0 0.294 /lib/systemd/systemd --user 16:35:36 exit 2682 0 0.004 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service/systemd-exit.service] 16:35:36 exit 2665 9 0.272 (systemd) 16:35:36 fork 2 parent [kthreadd] Time Event PID Info Duration Process 16:35:36 fork 2683 child [kworker/u16:5] 16:35:36 exec 2683 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service/init.scope] 16:35:36 fork 2 parent [kthreadd] 16:35:36 fork 2684 child [kworker/u16:4] 16:35:36 fork 2 parent [kthreadd] 16:35:36 fork 2685 child [systemd-cgroups] 16:35:36 exec 2684 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service] 16:35:36 exec 2685 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice] 16:35:36 exit 2683 0 0.005 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service/init.scope] 16:35:36 exit 2685 0 0.005 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice] 16:35:36 exit 2684 0 0.007 [/lib/systemd/systemd-cgroups-agent /user.slice/user-0.slice/user@0.service] 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2686 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2687 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2688 child /lib/systemd/systemd-udevd 16:35:36 fork 233 parent /lib/systemd/systemd-udevd 16:35:36 fork 2689 child /lib/systemd/systemd-udevd 16:35:36 exit 2687 0 0.014 /lib/systemd/systemd-udevd 16:35:36 exit 2689 0 0.013 /lib/systemd/systemd-udevd 16:35:36 exit 2686 0 0.015 /lib/systemd/systemd-udevd 16:35:36 exit 2688 0 0.015 /lib/systemd/systemd-udevd I suspect some of this overhead explains the slower responsive feel to the brightness buttons. Anyhow, seems like a bit of an overkill for all these processes to be running especially compared to Xenial. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1626651/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp