Created attachment 103956 [details] screenshot I'm using FPS "effect" to watch FPS drops and when I'm resizing an empty Kate windows - FPS drops down to 20-30fps. Also there are constant lags during usual operations, like windows switch, show desktop, etc. This bugs disperses in some versions and then comes back again... To remove tearing I'm using: Option "metamodes" "nvidia-auto-select +0+0 { ForceFullCompositionPipeline = On }" in xorg.conf In compositor settings: Rendeing backend: OpenGL 3.1 vsync: never According to system monitor: X process eats 25% of CPU during resizing. nVidia GTX 960 and 375.26 driver linux-4.4.39 Qt 5.6.2
Created attachment 103959 [details] attachment-28549-0.html The screenshot you included has a this is not a benchmark. But you used it as that. Any information gathered from it is useless. From what I understand your issue is high cpu usage in xorg. You should report this to xorg.
But it shows actual data. It's not like fps dropped only in this widget. I see this lags by myself. According to portage, last time I updated xorg at 09/19/2016. But this bugs begun few weeks ago. And the last kwin update 01/30/2017. Bingo!