Botond Ballo [:botond] Reporter
	Description • 9 years ago

STR:
  1. Run the latest nightly on Linux.
  2. In about:config, set layers.async-pan-zoom.enabled to true.
  3. Load http://people.mozilla.org/~bballo/grid.html.
  4. Scroll with the mouse wheel.

Expected results:
  The page scrolls at the same speed as with APZ disabled.

Actual results:
  The page scrolls more slowly than with APZ disabled.
  This is particularly noticeable if you're moving the mousewheel fast,
  and if you're relying on the momentum from a mouse-wheel scroll.

	Botond Ballo [:botond] Reporter
	Comment 1 • 9 years ago

To be clear, by speed here I'm talking about the amount by which the page's scroll offset changes in response to a given wheel gesture, not to painting or compositing speed.

	Botond Ballo [:botond] Reporter
	Comment 2 • 9 years ago

Sounds like this might be the same issue as bug 1139220.

	Botond Ballo [:botond] Reporter
	Comment 3 • 9 years ago

The speed of mouse wheel scrolling has improved a lot in spite of the fact that a fix for bug 1139220 has not landed yet. I'm not sure what changed.

	Botond Ballo [:botond] Reporter
	Comment 4 • 9 years ago

Tested this with the bug 1139220 fix in place. The wheel scrolling speed is now comparable to non-APZ.