Comment 86 for bug 125970

Who knows why, but the last two comments are absolutely right!
Current trunk builds are displaying these much, much better than previous ones.
Bungie and the euronet.nl site both still consume 100% CPU on my machine, but
scroll (relatively) smoothly.

The original test cases all scroll beautifully, with negligible (~2%) CPU use. I
would probably have to consider this fixed :)

Oddly enough, though... I did some testing using variations of the 100-div test
case (11 divs, 22, 33, etc) and found that CPU use stays that low until about 25
fixed divs are present. After that, I get odd spikes, until at 30 I have pretty
much solid 50% or above usage. From there it rapidly hits 100%, but (as seen in
the bungie site) even with huge numbers of such elements, the 100% usage doesn't
translate to poor performance. Yay!

I wonder why CPU use is behaving so oddly... I'd have expected something more
linear. It feels like it's having to "clean up" after drawing a certain number
of frames, and as you increase the amount of drawing it has to keep track of,
that cleanup becomes less erratic and more constant. Then again, I have no idea
what I'm talking about. =P

In other news, I think the change comes from bug 205893, and after reading
through that one and bug 284978, I think I have an idea of what's going on in
the above two paragraphs, too. That's all I have time for tonight though. I
guess I would consider this resolved.