After I connect external monitor, Xorg and migration/0..3 processes start taking cpu time permanently, only until I drag some window onto external monitor (and the desktop background is shown on the second monitor). Reproducible: Always Steps to Reproduce: 1. Run plasma5 session with kwin 2. connect external monitor Actual Results: Xorg and migration/0..3 processes start taking cpu time permanently, black background on the second monitor, see a screenshot with top output Expected Results: no slowdown, background image is displayed on second monitor (the same as for primary one) if I drag some window onto external monitor, then desktop background is shown on the second monitor and the perceived slowness disappears
Does this also happen w/ suspended compositor? (SHIFT+Alt+F12)
Created attachment 90771 [details] top output, black background on the second monitor
The migration processes is the kernel, moving around threads among CPUs. The actual culprit will be sth. different - i'd say either kwin or plasmashell. Try to kill them one by one to see what might be the cause. (Start w/ plasmashell - killing kwin means you cannot easily pass the input focus around. Do "pkill kwin_x11; sleep 120; kwin_x11 &" to have two minutes for testing w/o kwin and a running WM afterwards.
Created attachment 90772 [details] screenshot after workaround
killing neither of them didn't help. i'll continue investigating...
maybe these migration threads are actually a preparation for crazyness of kded5? described in the bug 337674
"possibly" - as this bug seems to focus around powerdevil, you could try to deactivate that module and see what happens.
@Dan: that sounds like the Qt-randr freeze?
Nick I've just tested this on Plasma/kwin from git master and I cannot reproduce the issue. Can you please test and confirm if this issue is still occurring or if this bug report can be marked as resolved. I'm setting status to "needsinfo" pending your response, please change back to "reported" or "resolved" when you respond, thanks.
Dear Bug Submitter, This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information as soon as possible and set the bug status as REPORTED. Due to regular bug tracker maintenance, if the bug is still in NEEDSINFO status with no change in 30 days the bug will be closed as RESOLVED > WORKSFORME due to lack of needed information. For more information about our bug triaging procedures please read the wiki located here: https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging If you have already provided the requested information, please mark the bug as REPORTED so that the KDE team knows that the bug is ready to be confirmed. Thank you for helping us make KDE software even better for everyone!
This bug has been in NEEDSINFO status with no change for at least 30 days. The bug is now closed as RESOLVED > WORKSFORME due to lack of needed information. For more information about our bug triaging procedures please read the wiki located here: https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging Thank you for helping us make KDE software even better for everyone!