The Moiré demo isn't running particularly well on my machine

[mstange]

The webrender demos on Servo's default new tab page don't run that well anymore, at least on my machine. For example, the moire demo doesn't seem like it does more than 20fps on this rather powerful Mac: http://browserhtml.github.io/browserhtml/components/about/newtab/demos/moire.html

(The other two demos on http://browserhtml.github.io/browserhtml/ that I tried are "transparent_rects" and "spheres" but they both seem to be broken, probably by other parts of servo?)

[trishume]

Same here, moire runs at 6fps on my integrated GPU and 3fps on my discrete GPU (the discrete GPU should be faster, dunno what's going on there 😐). When I open the same page in Chrome it runs at 60fps on either GPU. This is on a 2014 15" Retina Display Macbook Pro with an Intel Iris pro and an Nvidia GT 750m.

Also given that it runs at 60fps in Chrome (at least nowadays) maybe it's no longer a good demo of webrender doing things other browser's can't, except for the fact that it demos the reverse right now.

The debug stats suggest that most of the issue is in the compositor CPU: