https://bugs.kde.org/show_bug.cgi?id=484323
Bug ID: 484323 Summary: High CPU load of kwin_x11 when locking the screen Classification: Plasma Product: kwin Version: 6.0.2 Platform: Neon OS: Linux Status: REPORTED Severity: normal Priority: NOR Component: general Assignee: kwin-bugs-n...@kde.org Reporter: kram...@kde.org Target Milestone: --- Created attachment 167654 --> https://bugs.kde.org/attachment.cgi?id=167654&action=edit EDID data SUMMARY Since the upgrade to 6.0 I experienced a spin up of my CPU fans every time the screen engages. I have now had time to investigate this a bit by logging into the system via SSH and running top/htop. When I locked the screen, kwin_x11 jumped from ~5% CPU to ~70% and Xorg from ~3% to ~50%. ksmserver also moved into the top three processes. I tried again and attached gdb to the running process, interrupting it now and then. At the beginning (let's say first 1-2 minutes) the backtrace often included the KWin::Edid constructor, mostly in some memory allocation calls. Later on I only manages to interrupt it while it was in some XCB call. I can also not reproduce on a second system with relatively similar software state (both KDE Neon with the same updates installed). Two potentially related hardware differences are GPU and number of monitors. Workstation (which runs into the CPU load issue): AMD Radeon RX 550 / 550 Series, 3 monitors Laptop (which does not have the issue): Intel UHD Graphics 620, only internal monitor STEPS TO REPRODUCE 1. lock screen 2. observe CPU load via remote connection OBSERVED RESULT kwin_x11 and Xorg (though one might "drag along" the other) jump in CPU load to about 10 times their usual load EXPECTED RESULT CPU load staying atthe same as the unlocked system. SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: KDE Neon 6.0.2 (?) (available in About System) KDE Plasma Version: 6.0.2 KDE Frameworks Version: 6.0.0 Qt Version: 6.6.2 ADDITIONAL INFORMATION AMD Radeon RX 550 / 550 Series, 3 monitors (all 1920x1080, one is from a different vendor). Attaching output of get-edid (and parsed via parse-edid) -- You are receiving this mail because: You are watching all bug changes.