SUMMARY Starting a NVIDIA Optimus machine with a monitor plugged into an output controlled by the NVIDIA card on wayland with kwin causes kwin_wayland to hog CPU on a single core, leading to very poor graphical performance. Works fine when no external monitors are plugged in. I've attached my kwin_wayland log below. https://pastebin.com/uJkPmC4f is the kwin_wayland log with monitors plugged in on boot. https://pastebin.com/WSz7BXXs is the kwin_wayland log without monitors plugged in, where everything works fine. STEPS TO REPRODUCE 1. Connect Optimus Laptop with NVIDIA outputs to external monitor 2. Start KDE OBSERVED RESULT EXPECTED RESULT Low CPU usage and responsive desktop SOFTWARE/OS VERSIONS Linux/KDE Plasma: (available in About System) KDE Plasma Version: 5.25.5 KDE Frameworks Version: 5.98.0 Qt Version: 5.15.6
*** This bug has been marked as a duplicate of bug 452219 ***