EXA - current status with Intel driver

Michel Dänzer michel at tungstengraphics.com
Mon Sep 24 07:43:59 PDT 2007

On Sun, 2007-09-23 at 17:19 +0200, Lukas Hejtmanek wrote:
> On Thu, Sep 13, 2007 at 06:57:57PM +0200, Michel Dänzer wrote:
> > > 
> > > So with the current head, you are able to get 1400+FPS in x11perf -shmput500?
> > 
> > I think so, but I'm away from that machine and probably won't be able to
> > confirm for another week at least.
> This problem seems to be gone with latest head of all the stuff (Xserver,
> drivers, mesa, drm, etc).

Actually, these still seems slow here on i945. Did you find out which
change(s) caused or fixed the problem for you?

> However, overal desktop experience is still worse than with XAA. Your EXA
> improvements seems to help a lot compared to the previous state. However,
> firefox scrolling eats so much CPU that ondemand governor switches to high
> frequency, this is not the case with XAA.
> (this page is taken as reference:
> http://gitweb.freedesktop.org/?p=xorg/driver/xf86-video-intel.git;a=summary)

I don't see any obvious candidates for big savings in a profile

> Text scrolling in gnome-terminal is much slower and much more CPU consuming.

Here the profile looks as though Carl Worth's glyphs-as-pixmaps changes
might help significantly.

Though as you're on i965 (right?), the bottleneck for you may simply be
the inefficient driver Composite acceleration hook for i965, see Carl
Worth's blog posts and XDS talk.

> Last but not least, resume from RAM does not work. (Not sure whether EXA or
> new Eric's stuff with buffer objects is the reason.)

It works on my radeon based PowerBook, so it seems unlikely due to EXA.
I can confirm though that even just switching to console and back to X
locks up the i945.

Earthling Michel Dänzer           |          http://tungstengraphics.com
Libre software enthusiast         |          Debian, X and DRI developer

More information about the xorg mailing list