I believe this happens because unattended-upgrades gets and releases the lock a couple times (such as between installing upgrades and then removing now no longer required automatically installed packages) and dies if it cannot re-aquire the lock (rather than gracefully handling it).
The high frequency is easily explained since apt-daily runs both unattended-upgrades and aptd (via dbus triggers both from Update-Post- Invoke-Success (or whatever it was called) and directly from the apt- daily script) and this sets up a race with a fairly high chance of hitting unattended-upgrades somewhere where it hurts. Even when it does not lead to a crash it often causes upgrades not to be installed. This can be seen by setting APT::Periodic::Verbose to 3 and monitoring the logs. Often one or another of the steps of apt-daily will fail because it could not acquire the lock. Hope this helps. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unattended-upgrades in Ubuntu. https://bugs.launchpad.net/bugs/1602536 Title: /usr/bin/unattended-upgrade:apt.cache.LockFailedException:/usr/bin /unattended- upgrade@1468:main:do_auto_remove:cache_commit:commit:_fetch_archives Status in unattended-upgrades package in Ubuntu: Confirmed Bug description: The Ubuntu Error Tracker has been receiving reports about a problem regarding unattended-upgrades. This problem was most recently seen with version 0.90, the problem page at https://errors.ubuntu.com/problem/19f99745d7dce5aea118eb31bfffcbdcdf238c4f contains more details. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unattended-upgrades/+bug/1602536/+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
