[ltp] X22 GL perfomance? [SOLVED!]

[Charles E "Rick" Taylor IV]

On Sun, 2006-06-04 at 17:09 +0100, Richard Neill wrote:
> > 
> > Since you've got an X22 there - here's an experiment.  (Close all
> > valuable programs while trying this!)  Open up an xterm run glxgears.
> > Open up Celestia and run its demo mode - letting it run alongside the
> > glxgears.  This trick would cause the machine to lock up when I used the
> > X22, and I'm curious to see if the bug's still around in the later
> > xorgs.  Sometimes the X22 would make it through the demo once, but a
> > second run of the demo alongside a running glxgears window would kill
> > it.

> Yes - it still hangs. Complete lockup - not even responsive to SysRq.

That sounds about right.  When the X22 locks up like that, it's *dead*.
No debug output - no log files - no magic sysrq - nothing.

I have a few tweaks from my X31 that I will try on the X22 that seem to
prevent this lockup (at the price of slightly decreased performance).
I'll let the list know how those work out.

> Further investigation:

>   Just 4x glxgears complete with moves/resize is OK. It ran for hours 
> without trouble.

That trick was iffy for me, too.  Sometimes it would lock up the machine
within a few minutes, while other times I got sick of messing with it
with no lockups.  

The celestia/glxgears combo seems much more efficient at locking
Thinkpads.  (It has even crashed X on my non-Thinkpad JVC MiniNote with
Intel 855 graphics chipset, but didn't cause a complete system lockup).

> Celestia + 1x glxgears = instant crash. Kernel didn't even manage to panic!

If you have driconf installed, run it and change "method to limit
rendering latency" to "busy waiting for the graphics hardware".  This
will probably make the GL windows stutter while glxgears is running, but
it might prevent the crash.  It doesn't seem to harm performance for
anything I've tried OTHER than glxgears.

I've tested the above driconf tweak on an X31, but I haven't tested it
on my X22 yet.

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