NVIDIA Pascal series graphic card: slow graphics operations
I’ve replaced one of my older monitors with a newer one, before I had DP,DP,DVI for my monitors, now I use DP,DP,DP. (DP = Displayport).
Tails doesn’t like that new combination though. While DP,DP,DVI would work, now with DP,DP,DP I can’t get Tails 3.2 to boot. I see the blinking cursor for a few seconds, then for 1 or 2 frames an error message appears, and then Tails seems to crash and no longer has any GPU output (monitors either black or saying “connect stuff”). DP,DP,HDMI also doesn’t work. It seems it was luck that DP,DP,DVI actually worked.
I did film it with my phone so that I’m able to read the error message, it is just one line:
[2.984265] nouveau 0000:03:00:0 DRM: Pointer to flat panel table invalid
Connecting only 2 monitors with DP,DP works fine, if I then connect a 3rd one while Tails runs, it crashes (shows some graphics corruption for a few seconds, then turns all monitors off).
My old monitor combination had only one 1080p monitor, now I have two. Even with only two 1080p monitors connected, it feels like graphics operations are running slower than they should. When dragging windows around, it isn’t fully smooth and it looks like the image is constantly “breaking apart”, as if “vsync” would be disabled. So it looks like if first the upper half of the monitor is updated, and then a while later the lower part is. The height where that cut is is random though, so it moves up/down all the time. So when dragging a window around, the upper half or third etc is sometimes 1 cm further to the left/right (depending in which direction you move it) than the lower half/third/whatever of the window. It is very ugly. I did see that already when my old 3 monitors were still working, it was just less intense.
One other example for it feeling “slow” is that if I open a youtube video (even just 720p) on one monitor, and try to use the browser on a website like this on the other monitor, even the scrolling in the browser starts to feel very laggy. If I pause the youtube video, scrolling feels way better. So I’m not sure if its actually fully software rendering everything or if the GPU stuff is only working in some very slow mode.
I have tried to play around with commands like nouveau.modeset=X and nouveau.noaccel=X, but setting those to either 0 or 1 doesn’t improve anything, either it does nothing or it makes it worse.
I am using a Nvidia GTX 1080, which is a Pascal Series GPU.
I already posted about the issue here: https://labs.riseup.net/code/issues/11831 And it was suggested to me that I should create a dedicated ticket about it.
I did test this suggested ISO now: https://nightly.tails.boum.org/build_Tails_ISO_feature-buster/lastSuccessful/archive/build-artifacts/tails-amd64-feature_buster-3.4-20171022T0917Z-f62837af72%2Bdevel%40dd985681bf.iso
And the issue is in fact partly fixed there. I can boot Tails, it does start, all 3 monitors work. It also feels a bit smoother, though its still far from perfect. So when a 720p youtube video is running, scrolling on another website is still slow and laggy. I also still see a lot of that “breaking apart” of the image (I’ve attached a gif showing the issue).
But it’s a lot better than 3.2, since in 3.2 Tails didn’t work at all. Will this fix be in 3.3?
Feature Branch: bugfix/15116-newer-nouveau-xorg-driver