Poor compositing performance on 965Q chipset with intel 2.2.1 driver

[Juliusz Chroboczek]

> An updated libpciaccess may help here - the frame buffer was getting
> mapped UC instead of WC.

On a 855GM, I'm seeing x11perf -shmput500 around 400 per sec.  Is that normal?

FWIW, /proc/mtrr indicates that the framebuffer is WC, but I understand
that's no longer a reliable indication.

(I'm running stock Linux 2.6.25.1 and Debian's X server 1:7.3+10,
which claims to be 1.4.0.90.)

                                        Juliusz