When Trying Out Tumbleweed, It's Easy To See Why OpenSUSE Leap Disabled Nouveau

[carewolf]

Either that, or the KDE code isn't following the rules for using OpenGL from multiple threads.

A kernel panic or driver crash is never user-lands fault. Even if they do something wrong, it should just have wrong results.

[TheBlackCat]

Either that, or the KDE code isn't following the rules for using OpenGL from multiple threads.

There are a lot of things that the Nvidia binary drivers do that aren't technically correct. There are even more compatibility hacks they do for game code that is doing it wrong. I've even heard that they give performance recommendations to game programmers that totally violate the rules but work faster with the Nvidia driver. Which is great for Nvidia but means AMD has to reverse engineer it or convince the game engine to use a different code path for AMD cards.

So anyway, just because some code works correctly for Nvidia or AMD drivers does not mean that code is correct and Nouveau is broken. It's possible Nouveau is broken, but also possible that it is following the rules as written while propriatary driver code is allowing multithreaded resource access that is technically against the rules.

KDE isn't developed with NVidia in mind. They didn't even have NVidia cards on-hand, someone had to go out to get them to reproduce the nouveau bugs.

[TheBlackCat]

This is the difference between the enterprise level Gnome desktop and non-QAed minor desktops. If your time equals value then stay away from experimental software.

Ignoring the fact that KDE has QA up the wazoo, Qt has a much larger enterprise backing than GTK does and it has problems with Nouveau as well.

[slacka]

Do KDE, SUSE, or mesa devs need any help with these bugs? Are they all properly reported? Do they need any API traces or anything else we can provide to help get this fixed? I love KDE Neon. Fortunately I'm on proprietary drivers, but I'd gladly switch to help them out.

[slacka]

Is there anything any of us with Nvidia hardware can do to help? Do mesa, SUSE, or KDE devs need bug reports, APItraces or anything like that?

[aht0]

Unfortunately, KDE on NVIDIA does not work well with the proprietary driver either if one is on an older card requiring the legacy version of the driver. A notable issue with the legacy proprietary driver is the Konsole that leaves a process behind on exit eating 100% cpu.

It does not work well with AMD either. At least on pre-R9 cards. Incredibly annoying flicker-flicker in Plasma5. (which does not happen on KDE4 using OpenGL rendering in KWin using "Native" mode). Playing with settings is no help.

[devsk]

I have observed the same three things that Michael mentioned in his post. EXACT same things. I have wondered for a while what was happening and tried a bunch of things. Updating to 4.9.0 kernel has reduced the artifacts but not fixed it completely.

I am running nouveau on GTX 750 Ti.

[devsk]

Michael: have you tried this off late with KF5 5.30, apps 16.12, and plasma 5.9?