This sounds like it might be the pulseaudio process getting stuck in a system call that's particular to your sound hardware/driver. Please try running 'lspci -k' and pasting the output here.
Also, the problem might not be audio-related at all. It might be some other part of your kernel that's hanging and pulseaudio is just mentioned in the syslog because it's the only one with realtime threads. That doesn't mean those threads caused the problem necessarily. Please also try the latest live image (just boot from USB and leave it running for a while): http://cdimage.ubuntu.com/daily-live/current/ ** Changed in: linux (Ubuntu) Status: New => Incomplete ** Changed in: pulseaudio (Ubuntu) Status: New => 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/1712858 Title: system freezes occasionally for several minutes Status in linux package in Ubuntu: Incomplete Status in pulseaudio package in Ubuntu: Incomplete Bug description: Occasionally, the system freezes: display does not show mouse move, clock display does not update itself, ssh impossible. But the machine remains pingable. This lasts for 2 to 20 minutes. This is with Ubuntu 16.04.2, now upgraded to kernel version 4.8.0-46-generic. At the end of the freeze, a bunch of messages get written to /var/log/syslog. Examples: Aug 19 00:03:48 quimper rtkit-daemon[2276]: The canary thread is apparently starving. Taking action. Aug 19 00:03:48 quimper rtkit-daemon[2276]: Demoting known real-time threads. Aug 19 00:03:48 quimper rtkit-daemon[2276]: Successfully demoted thread 2607 of process 2275 (n/a). Aug 19 00:03:48 quimper rtkit-daemon[2276]: Successfully demoted thread 2606 of process 2275 (n/a). Aug 19 00:03:48 quimper rtkit-daemon[2276]: Successfully demoted thread 2604 of process 2275 (n/a). Aug 19 00:03:48 quimper rtkit-daemon[2276]: Successfully demoted thread 2275 of process 2275 (n/a). Aug 19 00:03:48 quimper rtkit-daemon[2276]: Demoted 4 threads. Aug 19 08:06:19 quimper rtkit-daemon[2276]: The canary thread is apparently starving. Taking action. Aug 19 08:06:19 quimper rtkit-daemon[2276]: Demoting known real-time threads. Aug 19 08:06:19 quimper rtkit-daemon[2276]: Successfully demoted thread 2607 of process 2275 (n/a). Aug 19 08:06:19 quimper rtkit-daemon[2276]: Successfully demoted thread 2606 of process 2275 (n/a). Aug 19 08:06:19 quimper rtkit-daemon[2276]: Successfully demoted thread 2604 of process 2275 (n/a). Aug 19 08:06:19 quimper rtkit-daemon[2276]: Successfully demoted thread 2275 of process 2275 (n/a). Aug 19 08:06:19 quimper rtkit-daemon[2276]: Demoted 4 threads. Aug 19 08:06:20 quimper systemd[1]: systemd-udevd.service: Watchdog timeout (limit 3min)! Aug 19 08:06:20 quimper systemd[1]: systemd-udevd.service: Main process exited, code=killed, status=6/ABRT Aug 19 08:06:20 quimper systemd[1]: systemd-udevd.service: Unit entered failed state. Aug 19 08:06:20 quimper systemd[1]: systemd-udevd.service: Failed with result 'signal'. Aug 19 08:06:20 quimper systemd[1]: systemd-udevd.service: Service has no hold-off time, scheduling restart. Aug 19 08:06:20 quimper systemd[1]: Stopped udev Kernel Device Manager. Aug 19 08:06:20 quimper systemd[1]: Starting udev Kernel Device Manager... Aug 19 08:06:24 quimper systemd[1]: Started udev Kernel Device Manager. Aug 19 15:04:55 quimper rtkit-daemon[2276]: The canary thread is apparently starving. Taking action. Aug 19 15:04:55 quimper rtkit-daemon[2276]: Demoting known real-time threads. Aug 19 15:04:55 quimper rtkit-daemon[2276]: Successfully demoted thread 2607 of process 2275 (n/a). Aug 19 15:04:55 quimper rtkit-daemon[2276]: Successfully demoted thread 2606 of process 2275 (n/a). Aug 19 15:04:55 quimper rtkit-daemon[2276]: Successfully demoted thread 2604 of process 2275 (n/a). Aug 19 15:04:55 quimper rtkit-daemon[2276]: Successfully demoted thread 2275 of process 2275 (n/a). Aug 19 15:04:55 quimper rtkit-daemon[2276]: Demoted 4 threads. Aug 19 15:04:55 quimper systemd[1]: systemd-timesyncd.service: Watchdog timeout (limit 3min)! Aug 19 15:04:59 quimper systemd[1]: systemd-timesyncd.service: Main process exited, code=killed, status=6/ABRT Aug 19 15:04:59 quimper systemd[1]: systemd-timesyncd.service: Unit entered failed state. Aug 19 15:04:59 quimper systemd[1]: systemd-timesyncd.service: Failed with result 'signal'. Aug 19 15:05:00 quimper systemd[1]: systemd-timesyncd.service: Service has no hold-off time, scheduling restart. Aug 19 15:05:00 quimper systemd[1]: Stopped Network Time Synchronization. Aug 19 15:05:00 quimper systemd[1]: Starting Network Time Synchronization... Aug 19 15:05:00 quimper systemd[1]: Started Network Time Synchronization. Aug 19 15:05:00 quimper systemd-timesyncd[26894]: Synchronized to time server 91.189.89.198:123 (ntp.ubuntu.com). Aug 20 06:03:28 quimper rtkit-daemon[2276]: The canary thread is apparently starving. Taking action. Aug 20 06:03:28 quimper rtkit-daemon[2276]: Demoting known real-time threads. Aug 20 06:03:28 quimper rtkit-daemon[2276]: Successfully demoted thread 2607 of process 2275 (n/a). Aug 20 06:03:28 quimper rtkit-daemon[2276]: Successfully demoted thread 2606 of process 2275 (n/a). Aug 20 06:03:28 quimper rtkit-daemon[2276]: Successfully demoted thread 2604 of process 2275 (n/a). Aug 20 06:03:28 quimper rtkit-daemon[2276]: Successfully demoted thread 2275 of process 2275 (n/a). Aug 20 06:03:28 quimper rtkit-daemon[2276]: Demoted 4 threads. Aug 20 15:09:22 quimper rtkit-daemon[2276]: The canary thread is apparently starving. Taking action. Aug 20 15:09:26 quimper systemd[1]: systemd-udevd.service: Watchdog timeout (limit 3min)! Aug 20 15:09:26 quimper rtkit-daemon[2276]: Demoting known real-time threads. Aug 20 15:09:26 quimper systemd[1]: systemd-udevd.service: Main process exited, code=killed, status=6/ABRT Aug 20 15:09:26 quimper rtkit-daemon[2276]: Successfully demoted thread 2607 of process 2275 (n/a). Aug 20 15:09:26 quimper systemd[1]: systemd-udevd.service: Unit entered failed state. Aug 20 15:09:26 quimper rtkit-daemon[2276]: Successfully demoted thread 2606 of process 2275 (n/a). Aug 20 15:09:26 quimper systemd[1]: systemd-udevd.service: Failed with result 'signal'. Aug 20 15:09:26 quimper rtkit-daemon[2276]: Successfully demoted thread 2604 of process 2275 (n/a). Aug 20 15:09:26 quimper systemd[1]: systemd-udevd.service: Service has no hold-off time, scheduling restart. Aug 20 15:09:26 quimper rtkit-daemon[2276]: Successfully demoted thread 2275 of process 2275 (n/a). Aug 20 15:09:26 quimper systemd[1]: Stopped udev Kernel Device Manager. Aug 20 15:09:26 quimper rtkit-daemon[2276]: Demoted 4 threads. Aug 20 15:09:26 quimper systemd[1]: Starting udev Kernel Device Manager... Aug 20 15:09:27 quimper systemd[1]: Started udev Kernel Device Manager. The process the rtkit-daemon talks about is, in all cases, /usr/bin/pulseaudio. $ ps auxw | grep 2275 haible 2275 0.0 0.0 519164 8576 ? Sl Jul11 3:47 /usr/bin/pulseaudio --start --log-target=syslog I have not used 'pavucontrol' on this machine in 3 months. Info: $ lsb_release -rd Description: Ubuntu 16.04.2 LTS Release: 16.04 $ apt-cache policy pulseaudio pulseaudio: Installed: 1:8.0-0ubuntu3.2 Candidate: 1:8.0-0ubuntu3.3 Version table: 1:8.0-0ubuntu3.3 500 500 http://de.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages *** 1:8.0-0ubuntu3.2 100 100 /var/lib/dpkg/status 1:8.0-0ubuntu3 500 500 http://de.archive.ubuntu.com/ubuntu xenial/main amd64 Packages To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1712858/+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
