I've upgraded one of my systems from 16.04 to 18.04 a few months ago and since the upgrade I've been periodically (sometimes a few times per day, sometimes once in a few days) sudden semi-freezes of my desktop system. Often when working with Visual Studio Code or using social media websites. The strange thing is the freeze is not complete. The keyboard doesn't respond to Ctrl-Alt-F*, the mouse buttons don't do anything, but the mouse pointer still responds as if the system is completely OK. I tried waiting to see if the system becomes responsive again, but even after an hour it doesn't, and my only resort is pushing the reset button of my machine.
System information:
HPZ420 PC
60GB RAM
NVIDIA graphs card
Evoluent (wired) vertical mouse
Microsoft natural keyboard
The biggest problem of cause is that because except for the mouse pointer my system becomes totally unresponsive, I have no way to check dmesg for any pointers about what might be happening at moment of becoming unresponsive but for the mouse pointer.
Has anyone else experienced any such problem after upgrading? Is there a way to get some logging happening that might help tracking down the problem after it occurs again? Or are there any known solutions for this problem if it is a known and not too uncommon problem?
I managed to get some more information using a little script that wrote dmesg to a log file every two minutes. This is the last part of my dmesg:
[ 5247.609140] nouveau 0000:05:00.0: fifo: SCHED_ERROR 0a [CTXSW_TIMEOUT] [ 5247.609162] nouveau 0000:05:00.0: fifo: runlist 0: scheduled for recovery [ 5247.609185] nouveau 0000:05:00.0: fifo: channel 15: killed [ 5247.609196] nouveau 0000:05:00.0: fifo: engine 7: scheduled for recovery [ 5247.609204] nouveau 0000:05:00.0: fifo: engine 0: scheduled for recovery [ 5247.609986] nouveau 0000:05:00.0: gnome-shell[1502]: channel 15 killed!
ls -al ~/.local/share/gnome-shell/extensions
. Report back to @heynnema