Composite really slow

[Evan K. Langlois]

Hi Everyone,

It could be my imagination, but it seems that the Composite extension is
much slower in Xorg than in the freedesktop.org/kdrive combination.
Even with xcompmgr off, I have issues if Composite is in the config
file.

I've tried lowering my screen resolution and reducing color depth, which
helps minimally, and if lowered enough I can compare the freedesktop.org
X server with Xorg, and while Xorg is more correct in its output, it
should be MUCH faster than kdrive based servers.  Its not.  It performs
as expected with Composite turned off, but the freedesktop.org X server
is plenty fast with this feature, and xcompmgr can be run (normally off
when I run Xorg) and even with shadows and fade effects its faster than
Xorg without the features (and Composite turned on).

I'm using the Radeon driver that ships with Xorg (not the binary) with
an ATI Radeon 9200SE with 128MB of RAM.  In my normal 1600x1200x24 bit
its night and day.  I'm wondering if Xorg is using my slower desktop RAM
(only 256MB and PC100 on a K6-2/550) for the off-screen bitmaps instead
of the 128MB on the card.  With Composite enabled, X uses nearly all the
CPU and apps suffer badly.  With it turned off, its quite snappy and
very useable.

Ideas?  I can post my Xorg if someone wants it but until then, I won't
waste the bandwidth as I have wacom drivers and all sorts of stuff in
there, so its kinda long.