via k8m890 very slow with vesa

Rene Rebe rene at
Wed Nov 29 05:14:38 PST 2006


On Wednesday 29 November 2006 14:02, Roland Scheidegger wrote:
> bob davis wrote:
> > I am the original poster and I have ubuntu edgy 6.10.
> > I ran the x11perf test with a few relevent tests
> > I also booted with a ubuntu 6.06 live dapper disk.
> > I attached both logs and you can see the tremendous slow down on scroll,
> > copy, and move window.
> >
> >    1200 reps @   6.1317 msec (   163.0/sec): Copy 500x500 from window to
> > window 24 reps @ 241.7143 msec (     4.1/sec): Copy 500x500 from window
> > to window
> That's pretty drastic. I've just tried it with 7.2 and it's still very
> slow. Since only operations seems to be affected which have to read from
> fb, but not write (so copy from window to pixmap is slow, pixmap to
> window is not), it looks to me like something goes wrong wrt shadowfb,
> which afaik should prevent having to ever read from framebuffer (though
> I could be wrong).
> Some quick oprofile run does not show anything from xorg or libfb
> promintently, the most prominent xorg function is WaitForSomething, but
> that's only 1.5%, most of the rest of the cpu time spent is inside the
> kernel with lock acquiring and releasing stuff...

Another hint: Review if the MTTRs are set up correctly. Somewhen in modular X 
this was broken but some time ago a variant of a fix I submitted to bugzilla 
was applied. Maybe something is still not right or broken again.


  René Rebe - ExactCODE - Berlin (Europe / Germany) | |
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