[ltp] Ubuntu Hardy: Intel video driver slow/broken on Thinkpad X41

[Charles E "Rick" Taylor IV]

On Sat, 2008-05-10 at 14:40 +0200, Shot (Piotr Szotkowski) wrote:
> Charles E Rick Taylor IV:

> > I've got a Thinkpad X41 tablet with an Intel 915 video chip.  I've
> > just installed Ubuntu Hardy 8.04 and have noticed that (among the
> > *rest* of the bugs) that 3D performance has dropped markedly compared
> > to the previous Ubunto (Gutsy 7.10).

> You can start tracking this by trying out the various workaronds
> for LP#177492: https://bugs.launchpad.net/ubuntu/+bug/177492

Of the various things in that bug report, the only thing that seems to
have any effect on 3D performance is putting INTEL_BATCH=1
into /etc/environment. Of the /etc/X11/xorg.conf tweaks, these two:

Option "AccelMethod" "EXA"
Option "MigrationHeuristic" "greedy"

were already defaults as of 5/8/08 (when I installed Hardy), and the
last one:

Option "ExaNoComposite" "false"

doesn't appear to have any effect.  I've turned off the fancy compiz
stuff anyway, as compiz and screen rotation (essential on a tablet)
aren't compatible.  The rotated screen doesn't update, and the cure is
(blindly) opening up and xterm and using xrandr to rotate the screen
back to the normal orientation.

By tweaking some of the options in Google Earth and Celestia, I've been
able to get them to run at least usably fast (turning off the atmosphere
in Google Earth mostly solves performance problems there, for example).
It's still slower than Gutsy, though, and I didn't have to do anything
special to xorg.conf or any of these apps there.  The i810 driver is
slightly faster than the intel one, but seems to suck more power, too.

-- 
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*  Charles E. "Rick" Taylor, IV <rick@rickandpatty.com>
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