Beryl black screen -7950GX2/Ubuntu/amd64 - when switching back from another X session

[Descore]

Hi,

I have tried and tried to find a solution to this problem but to no avail so I decided to post here. I have seen some similar problems but none are exactly the same as what I am seeing.

Setup:

* XFX GeForce 7950GX2
* Asus M2N32SLI-Deluxe motherboard, latest BIOS
* Ubuntu Edgy amd64
* NVidia driver 9746 (also tried 9742 with same result)
* Kernel.org 2.6.20 kernel (also tried Ubuntu 2.6.17-11 with same result)
* Beryl 0.1.2-0ubuntu2

What happens is this:

1) User 1 is logged in and Beryl is active.

2) I switch away to User 2 with the Switch User feature (this creates a different X server).

3) User 2 logs in, also uses Beryl this works ok.

4) I switch back to User 1.

5) Now I only see a black screen with the mouse pointer.

At this point I can (from another PC) log in and killall -USR2 beryl-manager, (which switches back to Metacity WM), this will *sometimes* work and at other times it will crash the X server.

If I disable Beryl before switching away, there is no problem when switching back. So something is not getting restored properly.

There is a related bug case on the Beryl bug tracker: http://bugs.beryl-project.org/ticket/928

I would surely appreciate any help. I need Switch Users to convince my wife that Linux is better than Windows...

Cheers,
Descore

[gcostes]

Have you tried selecting "Force AIGLX" as the "Rendering platform" in the "Advanced Beryl options"? Just a thought...

[Descore]

Originally Posted by gcostes

Have you tried selecting "Force AIGLX" as the "Rendering platform" in the "Advanced Beryl options"? Just a thought...

That's got it.. Well almost.. Now the screen turns white when I switch back, but if I type in the password it comes back. Which is acceptable if not ideal!

So thanks a lot. What does this option actually do? I thought "Nvidia" rendering was the way to go with these drivers.

/Descore

[Descore]

5 minutes later

It looked like it worked at first but after having it switched to AIXGL for a bit I realize that the performance is horrible compared to NVidia rendering.



I'm talking a factor 8 slowdown in frame rate when moving around the transparent cube. It becomes a bit useless like that, feels like running a Ferrari at 30 miles per hour. So I am still looking for a better solution.

/Descore

[independence]

I have the same problem, windows turn black after a while. It seems to relate to how many windows I have open, and how big those windows are. I can for example get the contents of the window back if I make it smaller in size.
I can also get the contents back of windows if I close a couple of other windows.
However, it's really frustrating not beeing able to use lot's of windows at the same time. It would be awesome if you could fix this bug! Everything else works perfectly!
Maybe it's some buffer or memory that's not big enough, and runs out after a while?

Edit1: Attached nvidia-bug-report.log from my system.

[gcostes]

Yes - AIGLX rendering is a software rendering while Nvidia (or auto) is hardware managed so yes ... this solution reduce the performance...

For me it is still acceptable (benchmark of 250 frames / sec while Beryl running and 50 frame / sec while playing with the 3D cube).

The black window problem when using the Nvidia proprietary driver is well known and as far as I know there is no other solution so far other than using the AIGLX rendering (or indirect rendering). Unfortunate...

[aronparsons]

I've been experiencing the same thing (which is not the more common "black windows bug"). If using NVIDIA as the rendering platform, if I take away focus from the display (either suspending to ram or switching to another VT), when I switch back the whole display is black and I can move the cursor for a few seconds. If I don't kill X within a few seconds, the machine stops responding to input and requires a hard reboot.

Using AIGLX solves this problem but is not ideal for performance and quality reasons. The framerates drop quite a bit using AIGLX, but not to the point where it hinders the beauty of Beryl; but knowing that using the NVIDIA rendering platform results in better performance, I would prefer to go that route. Also, using AIGLX introduces horrible video playback; lots of tearing occurs in videos and I can not solve that issue. I have tried changing the xine video driver between xv and opengl, but the issue stays. Using NVIDIA for the rendering platform in beryl results in perfect video playback.

One thing I did find that is a stop-gap for this problem is explicitly enabling AIGLX in my xorg.conf sped the rendering up; before doing this, many of the animations were jerky while using AIGLX as the platform. It may help someone in the meantime until a new driver is released.

My setup: openSuSE 10.2 x86_64, 7300GT, 9746 driver, beryl (latest svn build)

[TiAmo74]

I have solved the problem by turning off the "Sync to VBlank" Feature in the Beryl settings.

[aronparsons]

Originally Posted by TiAmo74

I have solved the problem by turning off the "Sync to VBlank" Feature in the Beryl settings.

That solved the black screen problem, but introduced a new one. When switching back to the VT, the screen is drawn correctly but only mouse movement is recognized. So basically, the same problem with a colorful screen instead of a black one. ;-)