Created attachment 126548 [details] .xsession-errors I am using a lenovo laptop t470p with intel graphics (bumblebee is installed and working on demand). Also using zawertun copr for latest plasma 5.18.1 Independent of the compositor setting (opengl 2,3 or xrender or tearing prvention) the laptop screen irregularily gets black for only a fraction of a second. This is very annoying,because a second screen connected to the laptop (using displayPort) stays on all the time, no black blinking at all... I don't have any tearing or stutter or something, just an irregular blink/blackout. I cannot even tell if the time in between the blackouts are regular. It just happens when working with the laptop, in my opinion less often after a fresh reboot, but the longer you work, the more often those blackouts appear. This all wasn't there in plasma 5.16.x, at least i never encountered any symptoms like this. Any help with this? Please....
oh, btw, it's plasma 5.18.2 already on fedora31
I was experiencing this too on openSUSE Tumbleweed for a time, but then it stopped happening. :/ I could never pinpoint what was causing it.
at least i'm not allone or hallucinating... Still happens on 5.18.4 I already did a fresh install of fc31 on the laptop, assuming it was caused by all those updates coming since fc27. But.... the problem did not disappear
i'm currently testing with KWin-lowlatency, up to now it seems to have stopped the irregular blinking. If this holds true (i continue testing), then maybe we have a bug to report to kwin/composer?
after a longer testing... sadly, the kwin-lowlatency doesn't help. Laptop screen still 'blinks'
My guess is that a graphics reset occurs from time to time. It would be really helpful if you run `env QT_LOGGING_RULES="*.debug=true" kwin_x11 --replace` and post the output after the screen turned black. You might want to redirect the output to a file and then attach the file here. Before attaching the file make sure that there is no any confidential data in it. Also, it would be useful to have dmesg output after the screen got black.
i recently captured on 'blink' event (see attached file) In comparison to the other file i have written (unsuccessfully), the only thing standing apart is this line: org.kde.kactivities.lib.core: Killing the consumer When the 'blink' occurred, i replaced kwin again to stop the logging and this is the file in the attachment... Hope this helps?
Created attachment 128849 [details] log with blink event
Created attachment 128850 [details] dmesg
dmesg is attached as well, starting yesterday. Nothing really interesting in there regarding the blink event
just one more thing (i know, this quote is 'stolen' :-) Something that looks quite similar to my 'blink' event is for example attaching a second monitor to the displayPort (miniDP). There you also get a quick 'reset' or 'blink' (screen goes black for a fraction of a second) when plugging in the connector. This just *looks* the same, i thought i'd mention it to describe the term 'blink' a bit better. I also had this blink when stopping/restarting the compositor with Alt-Shift-F12. But this only happens from time to time, normally the switching here is without blink-effect. And, using the kwin_x11 --replace command caused this effect *sometimes* (e.g. if i do it right now several times, i can only see the compositing effects (windows get shadows for example) or a redraw of the whole desktop contents) - but no 'blink'
I'm currently testing with disabled TLP, this seems promising Anyone else with this blink-problem had tlp active? Is tlp necessary at all any more? (esp. since fedora31 and following did improve energy saving mechanisms?)
nah, blinking is still there. I'm out of ideas right now, any help?
after looking at similar reports of laptop screen problems i found the advice, to add i915.enable_psr=0 to the kernel-commandline. This seems very promising, i continue testing...
good news... the psr (panel self refresh) disabling fixes the problem!!! Questions: - what changes in kwin/plasma since 5.16.x caused this problem? I mean, according to the solutions i found on the net, the psr was introduced somewhere around kernel 4.x, and this is waaay older than plasma 5.17.x, where this bug occurred the first time on my system? - Now, since the culprit is found, can we do anything to solve the problem without kernel-commandline mangling? New kde/plasma users won't spend so much time on finding solutions to this problem?
Can you confirm if this is still an issue with any newer kernel
difficult, as i moved on to an p14s.gen4/amd in the meantime I started the t470p once in a while, but not for extenden/serious work any more.