Re: control-center 2.13.90 released

[Pat Suwalski <pat suwalski net>]

Owen Taylor wrote:
> I think the first step is for someone to simply spend a little time
> figuring out what is slow:
>
>  - Gradients
>  - Scaled images
>  - Solid color backgrounds?

30 seconds of experimentation shows me that scaling and filling are 
slow, while tiling is very fast. The very strange discrepancy is that 
when setting an image smaller than the screen, centering is slow!

> If we are scaling images *via Cairo* that is known to be slow with
> older X servers; if investigation proves that actually is the problem,
> it can be worked around.

All of my observations are on X.org 7.0.0 with the radeon driver. There 
were previously (6 months ago?) bigger performance problems, but when I 
opened a freedesktop bug about it, the whole XaaOffscreenPixmaps issues 
was brought up. I don't know how that concluded. Adding the Exa 
extension slows down my r200 card another 2-3 times. But that is getting 
off-topic.

It used to be relatively simple to spot gtk/gdk drawing problems. Now, 
it's difficult to say where the problems are, given the 
gtk-cairo-exa-newX stack.

For people interested, there is a good discussion in a now-closed bug 
that addresses some of the slow drawing issues, which I think at this 
point are history:

	http://bugzilla.gnome.org/show_bug.cgi?id=314616

But I wonder if the relevant functions don't need to be revisited? Does 
anyone have any suggestions on how to profile these issues?

--Pat