1487412 - Off-screen animation throttling causes stuttering in 3D transform animation

Status: NEW

(Core :: DOM: Animation, enhancement, P2)

Description

[Miko Mynttinen]

Off-screen animation throttling causes considerable stuttering in the 3D transforms demo: https://keithclark.co.uk/labs/css-fps/nojs/

For whatever reason, this is more noticeable on Windows. On MacOS, the stuttering starts in the middle of the second "scene".

Profile of throttling happening at around seven second mark: https://perfht.ml/2PLUy2W

Setting pref dom.animations.offscreen-throttling;false makes the stuttering go away.

Comment 1

[Miko Mynttinen]

This might be a duplicate of bug 1424506. Hiro, could you please take a look at this?

Comment 2

[Boris Chiou [:boris]]

This might be related to Bug 779598 (i.e. we cannot run preserve-3d off the main thread).

Comment 3

[Boris Chiou [:boris]]

(In reply to Boris Chiou [:boris] from comment #2)

This might be related to Bug 779598 (i.e. we cannot run preserve-3d off the main thread).

Unfortunately, Bug 779598 doesn't help. We still have to find the root cause. Maybe we can tweak some for offscreen throttling stuff for cases like this.