I have upgraded to pulseaudio 1:8.0-0ubuntu3.3. At the same time, my system got upgraded to use a 4.10 kernel (instead of a 4.8 kernel).
The effect: The lockups got worse: - machine not pingable during the lockup, - freeze for 2 hours or more; I decided to reboot. Now I downgraded to a 4.8 kernel. The effect: The lockups are still there, but are temporary: - machine remains pingable, - freeze for only a couple of minutes. The latest such freeze (at 18:57) led to these syslog messages: Sep 11 18:58:55 rtkit-daemon[2231]: The canary thread is apparently starving. Taking action. Sep 11 18:58:55 rtkit-daemon[2231]: Demoting known real-time threads. Sep 11 18:58:56 systemd[1]: systemd-timesyncd.service: Watchdog timeout (limit 3min)! Sep 11 18:58:56 rtkit-daemon[2231]: Successfully demoted thread 2612 of process 2230 (n/a). Sep 11 18:58:56 rtkit-daemon[2231]: Successfully demoted thread 2611 of process 2230 (n/a). Sep 11 18:58:56 rtkit-daemon[2231]: Successfully demoted thread 2610 of process 2230 (n/a). Sep 11 18:58:56 rtkit-daemon[2231]: Successfully demoted thread 2230 of process 2230 (n/a). Sep 11 18:58:56 rtkit-daemon[2231]: Demoted 4 threads. Sep 11 18:58:57 systemd[1]: systemd-timesyncd.service: Main process exited, code=killed, status=6/ABRT Sep 11 18:58:57 systemd[1]: systemd-timesyncd.service: Unit entered failed state. Sep 11 18:58:57 systemd[1]: systemd-timesyncd.service: Failed with result 'signal'. Sep 11 18:58:57 systemd[1]: systemd-timesyncd.service: Service has no hold-off time, scheduling restart. Sep 11 18:58:57 systemd[1]: Stopped Network Time Synchronization. Sep 11 18:58:58 systemd[1]: Starting Network Time Synchronization... Sep 11 18:59:00 systemd[1]: Started Network Time Synchronization. Process 2230 is (again) pulseaudio. ** Changed in: pulseaudio (Ubuntu) Status: Incomplete => New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1712858 Title: system freezes occasionally for several minutes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/1712858/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs