Terrible performance with backing-store enabled.

[Clemens Eisserer]

> This is because backing-store is implemented in a very nasty (but card
> memory efficient) way.  Using xcompmgr -a will give you what you want,
> most likely, but with much better performance.  It would be nice to
> implement these features on top of the Composite extension, I think.

Thanks for the tip!

I already tried "xcompmgr -a" but the results where holes in windows
and rendering artifacts - this is as far as I can imagine related to
the NVidia driver - I already sent a bug-report to Nvidia.
However performance is MUCH better using xcompmgr, it gives exactly
(in terms of performance) what I expected.

Does anybody know how xcompmgr does manage memory, if e.g. an opengl
application would like to "upload" textures but almost all memory is
used by xcompmgr - will the xserver fall back to non-backing windows
or will the OpenGL application have to use RAM?

Thanks a lot, lg Clemens