Xorg dual-head fail

[Adam Williamson]

On Sun, 2009-03-01 at 19:21 +0200, Ahmed Kamal wrote:

> Does something as common as attaching an extra monitor to a laptop,
> require that much voodoo ..! How would a "normal" user react ! I wont
> try to mention how to resolve the problems mentioned here, since you
> guys know this better than I do ... I'm not whining either, I'm simple
> mentioning somthing is definitely wrong, with the hope of spurring
> action to make things better

krandrtray is fairly rubbish. The best UI to use is
gnome-display-properties, which handles it very well.

The issue with having to set Virtual is that the intel driver can't yet
dynamically re-allocate the framebuffer to accommodate a growing
display. Theoretically we could default to a huge framebuffer, but
there's two problems with that - above 2048 pixels in either axis, 3D
acceleration stops working, and also, the bigger the framebuffer, the
more RAM it uses, so if you set a 2048x2048 framebuffer on a 1024x480
display (hint: netbooks have small screens and not much RAM) you're
wasting about 45MB of RAM.

The Intel driver devs (who are reading this, I'm sure, and apologies in
advance for the jab, guys) have been promising dynamic reallocation of
the framebuffer Real Soon Now for a while ;). I think the last I was
told is that it's part of the whole GEM thing that's being worked on
now. Once that's sorted, it will all work without any messing about
required, you'll just be able to run gnome-display-properties and
re-arrange the screens however you like.
-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Fedora Talk: adamwill AT fedoraproject DOT org
http://www.happyassassin.net