I was able to solve my mysterious gtk specific font rendering issues in selection lists by changing video cards from an old radeon 2600 pro to a nvidia gt 640, but this unleashed a whole host of entirely new woes...
While the opensuse one-click driver install makes it easy to install nvidia's drivers, this is sadly really only the beginning. First, there was video tearing in compositing in KDE itself. Then there was video tearing issues in media playback. Finally, sometimes while logging in compositing would be disabled, either for KDE plasma itself (hence the panel) or for plasma and all applications. Simply changing KDE Desktop Effects compositing type to "opengl", nor playing with tearing prevention, had any useful effect for any of these host of problems on their own.
All of these issues can be solved, but it requires extensive tuning beyond what I think should have ever been nessisary. Much of the advice offered online is also now either obsolete or just plain incorrect. This is what I did to get a stable Nvidia driver working; no tearing, even in vlc/video playback, stable login:
First, we begin in xorg.conf under section "Screen":
Option "AccelDFS" "1"
Option "GARTSize" "64"
Option "EnablePageFlip" "1"
Option "ColorTiling" "1"
Different people offered had different advice for this, but these were the only ones that seemed to offer actual improvement, at least with the present drivers, and believe me, I tried all the other suggestions and variants people had suggested in the past...
Second, we need to have something like a ~/.kde4/env/nvidia.sh, set to start "pre-kde" in KDE startup settings, as this seems to guarantee KDE will login with nvidia driver support correctly, and also lets us fix several other issues:
I forget who suggests the__ GL_YIELD, but it made an important difference. The sleep is also needed to make sure the nvidia settles down before KDE plasma starts up, otherwise sometimes, as noted, I would login without compositing enabled...
The reason I load nvidia-settings, is that was also nessisary to use that to create a ~/.nvidia-settings-rc. The most important setting seems to be to set power mizer to maximum performance; it seems the reclocking based on activity is broken/syncs poorly on their crappy drivers. I also disable opengl sync to video blank, as it seems to conflict/be redundant with the kde settings, and anyway I found it unneeded. This finally let vlc play video without it's own tearing issues...
However, there is one ugly issue that remains with #nvidia
's crappy driver. #Kded4
memory leaks like a sieve with it. Typically up to a gig of resident ram in less than a week. Memory leak issues with kded4 have been reported now for MULTIPLE YEARS in #KDE
bug tracking now (+Aaron Seigo
) with no fix in sight even as per KDE 4.13. From reading the many now long bug threads for this, I do not think anyone had correlated them to Nvidia's crappy drivers specifically before, though. I did note many (though I do not think all) who commented on this who included info on their hardware also did report using either nvidia or radeon (catalyst driver?) cards.
The only work-around for kded4 memory leaks with nvidia I have been able to find is far more drastic. It seems to be the power manager (powerdevil) is the culprit here, as suggested in the many bug commentaries, and at least this also matches my experience, though it is hard to say how the crappy nvidia drivers interact with power management in such a horrible way. Of course disabling KDE power management seems to currently wonk out activities where truly wierd behaviors happen. If your going to disable power devil, you have to forgo and disable activities in KDE startup too.
Once you do that though, it does seem you do have a long term stable KDE workstation again. It is now very clear to me why +Linus Torvalds
the middle finger, and I agree, especially after this experience, they truly still do deserve it.
How nvidia could have gone from a zero to a hero I think would have been by trully facilitating development of the #nouveau
drivers. Now that they have figured out how to do reclocking, I gather despite Nvidia's a-hole attitude, I hope to soon be able to abandon Nvidia's crapware drivers forever and use decent power management again. Oh, but at least the original font rendering issue which started all this is definitely gone :)...