Firefox OS/Performance/Graphics/UniformityMeasure

Measuring Frame Uniformity

Enable the preference 'layers.uniformity-info'. Then you will get a lot of spew in adb logcat. Next, update and install orangutan - https://github.com/wlach/orangutan.

Then, run orangutan to create a scroll. At the same time, make sure you have adb logcat open. Copy / paste all the logcat into the frame uniformity tool:

http://people.mozilla.org/~mchang/FrameUniformity.html

Then push Reload Data, which should give you a graph of frame uniformity. The smaller the difference in frames, the better.