very bad, and very weird, scrolling text performance xorg 1.5.3 intel 2.5.1 GM965

[Clemens Eisserer]

Hi Johannes,

Greeting from Austria ;)

> I must say I'm also very unhappy with the intel driver's degrading
> performance. I don't have any hard numbers, but the "snappiness" of esp.
> scrolling text has gone nothing but downward over the last months.
There has been a lot of refactoring/rewriting going on in the
intel-driver over the past half year or so.
So previously well tuned code (or at least heavily quirk-fixed to
provide acceptable speed) was rewritten and re-designed and that needs
some time.

I also ran some benchmarks, and compared to earlier releases I see
halfed throughput for some cases.

> It's nice to see/read developers experimenting with new acceleration
> architectures and all, but if there is no net gain over XAA, what is it worth
> anyway?
If the driver is broken, why do you blame the accaleration architecture ;)
XAA is mostly software-only, so if the driver is slow it doesn't hurt
a lot - most rendering especially to pixmaps is done by the CPU
anyway.

- Clemens