Hey guys, running Debian Stretch here with plasma 5.8 in a lab environment with about 15 machines. And from time to time, plasmashell will creep upto 100% cpu usage, then lock up any taskbar/paging actions. You can still move the windows around on your current desktop, but can't jump out of the desktop. If you wait it out, it will generally go back down, but you cannot switch desktops or use the K button. alt-f2 works and I can kquitapp && sleep 5 && plasmashell and it will generally get it going again, until it pegs once more.

Doing some googling, I've read of a bug with plasma and animated system tray icons. I don't believe that to be the case here, as these systems other then KDE are stripped pretty bare. The only system tray items are Notifications, Korganizer Reminder Daemon, Batt and Brightness, Device notifier, volume, clip board and the odd updates item.

All of the PCs in the lab are the same build/brand, nvidia driver, 2 monitors. The issue is definitely intermittent, as it hasn't/doesn't effect everyone. The only behavior that seems to be consistant when it does get to 100% is the users are entering the same virtual desktop. This particular desktop is displaying a 5-6 high resolution satellite photos looping (weather shots). And it does seem to be the case from reports that it's always upon entering this particular desktop that starts to lock up the system.

Checking .xsession-errors, and there appears to be around 30k entries complaining about bad window (see attached kde.paste.org link)

https://paste.kde.org/plnqjfdkg

The line

QXcbConnection: XCB error: 3 (BadWindow), sequence: 14278, resource id: 165675028, major code: 142 (Unknown), minor code: 3

is the one repeated, with incrementing sequence values, and different resource ids for each. Major/minor are the same for the block of 30k errors.
So if I go over to the workstation, kill off the satellite animation loops and restart plasmashell, it seems to come back up

posted the contents of the to qdbus org.kde.KWin /KWin supportInformation

https://paste.kde.org/pq097brkv

I've tried disabling compositing, but that user also had issues with plasmashell goint to 100%.

Any help would be appreciated!

Thanks

Ryan