*** If you're not sure this is actually a bug, instead post about it at https://discuss.kde.org If you're reporting a crash, attach a backtrace with debug symbols; see https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports Please remove this comment after reading and before submitting - thanks! *** SUMMARY STEPS TO REPRODUCE 1. Have a 4k monitor (144hz) on an nvidia graphics card 2. Lock screen 3. ssh in and run nvtop OBSERVED RESULT Notice that kscreenlocker_greet uses over 1GB of VRAM EXPECTED RESULT It uses maybe a few hundred, but not 1GB, I use a black colour as the background SOFTWARE/OS VERSIONS KDE Plasma Version: 6.1.5 KDE Frameworks Version: 6.6.0 Qt Version: 6.7.3 Kernel Version: 6.10.10-arch1-1 (64-bit) Graphics Platform: Wayland Processors: 32 × AMD Ryzen 9 5950X 16-Core Processor Memory: 62.7 GiB of RAM Graphics Processor: NVIDIA GeForce RTX 4090/PCIe/SSE2 ADDITIONAL INFORMATION
Does the VRAM usage change if you use different backgrounds types?
I've tried "Image" and "Slideshow" and they both use over 900MB of VRAM.
Thanks. Does it create an observable problem at all?
I mean, it uses a lot of VRAM. My use-case is that sometimes I use my desktop (which has the best GPU) to run local LLMs while it's idle, if kscreenlocker uses 1GB of that, that's a lot less context tokens I can use for the LLM.
After messing around with it a bunch more, I find that commenting out the WallpaperFader part of /usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockScreenUi.qml (not sure if it's a different path depending on distro) reduces the VRAM usage by half, down to about 500MB rather than almost a gig.
For what it's worth, when my laptop is in locked mode the fans speed up a lot. I have tried checking into what process is causing this but I am not sure. When I exit the lock screen the fans go back to normal and cpu and ram usage falls.
I see this as well with Fedora 42. A locked, monitor into powr down mode, vram usage is 286MiB which is double plasmashell. kwayland-6.5.3-1 kernel 6.17.9-200 Another machine, active in usage with two account operational. kscreenlocker at 254Mib with just a plain colour background. Event turned the clock off on that login screen. strace of the kscreenlocker just repeats these lines until I do something. ppoll([{fd=4, events=POLLIN}, {fd=13, events=POLLIN}, {fd=39, events=POLLIN}, {fd=46, events=POLLIN}, {fd=47, events=POLLIN}, {fd=48, events=POLLIN}, {fd=288, events=POLLIN}], 7, {tv_sec=0, tv_nsec=998000000}, NULL, 8) = 0 (Timeout) newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, st_size=2332, ...}, 0) = 0 ppoll([{fd=4, events=POLLIN}, {fd=13, events=POLLIN}, {fd=39, events=POLLIN}, {fd=46, events=POLLIN}, {fd=47, events=POLLIN}, {fd=48, events=POLLIN}, {fd=288, events=POLLIN}], 7, {tv_sec=0, tv_nsec=0}, NULL, 8) = 0 (Timeout)