The flurry of uevents like KERNEL[2471.462139] add /kernel/slab/:atA-0000192/cgroup/dentry(4399:[email protected]) (cgroup) ACTION=add DEVPATH=/kernel/slab/:atA-0000192/cgroup/dentry(4399:[email protected]) SEQNUM=4916 SUBSYSTEM=cgroup
are new with kernel 4.8. This can easily be reproduced/observed with udevadm monitor -e --udev pkexec /usr/lib/unity-settings-daemon/usd-backlight-helper --get-brightness This causes lots of uevents in kernel 4.8, but zero with 4.4. This explains the dozens of udev workers that get forked and slow down processing -- under 4.4 it's much faster, a latency of ~ 0.1s or 0.2s; not quite instantaneous, but much better than under 4.8. This might be the same root cause as bug 1627108 and bug 1626436, particularly the latter -- if the creation/change of every cgroup causes 3 uevents, then during boot (when lots of services get started and lots of cgroups get created) tons of these uevents fire. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1626651 Title: brightness keys are handled slower in Yakkety than Xenial To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/policykit-1/+bug/1626651/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
