https://bugs.kde.org/show_bug.cgi?id=316348
--- Comment #32 from Joachim Wagner <jwag...@computing.dcu.ie> --- (In reply to Martin Gräßlin from comment #30) > According to the backtrace: you are using llvmpipe, which means OpenGL is > emulated on the CPU. Of course that's not going to be efficient. This is a default install of OpenSUSE 42.1 in a VM. Hardware graphics acceleration is not an option. I've a few VMs and I'd like keep runlevel 5 as it's handy to have a graphical login on occasions. On a machine with hardware graphics acceleration, if the screen is re-drawn as soon as the previous drawing is finished, this will still be a huge waste of power on the GPU (not visible in the CPU usage stats of "top"). A simple way to check this (without a power meter) may be to check how often per second the screen is re-drawn. Ideas for workarounds (in no particular order): (0) I tried setting screen energy saving to 2 minutes in KDE system settings and locking the screen (rather than logging out) hoping that re-drawing would stop after 2 minutes. No success. (1) Send SIGSTOP/SIGCONT as needed (seems to work but have to remember why the login screen is frozen) (2) Pick brains of cgroups expert how to apply cpu.cfs_period_us and cpu.cfs_quota_us to this situation (3) Check source code and add sleep(0.02) in the re-drawing loop (4) Lower the blinking frequency of the cursor (if this is what causes the re-drawing) (5) Learn how to configure a non-KDE login screen in OpenSUSE that can still start KDE (6) Find out whether kscreenlocker can show a simple framebuffer-based login screen To the gdb experts here: Can I easily find out how often the screen is re-drawn and how, for example by obtaining a list of functions and how often they have been called in the last second or since the last query? Any suggestions? -- You are receiving this mail because: You are watching all bug changes.
