1316658 - Bad horizontal swiping performance on https://www.cnet.com/tech-today/

Status: RESOLVED INCOMPLETE

(Firefox for Android Graveyard :: Toolbar, defect, P3)

Description

[Dennis Schubert [:denschub]]

In this example, the horizontal swiping performance in Fennec is somewhat bad. On Desktop, transitioning between the slides is fast and fluent, but it's really slow and choppy on Fennec. As far as I can see, the site only does modify translateX() on the div inside div.contentParent.

The content slides are just divs laying next to each other, all visible and as far as I can see, nothing happens except for altering the translateX() property.

Comment 1

[Carmen Fat [:cfat] - Ecosystem QA]

I was able to reproduce the issue using Nexus 5 (Android 6.0.1).
Setting the flags accordingly.

Comment 2

[Kartikaya Gupta (email:[e-mail])]

I'm not sure if there's much we can do here. The fact that the elements are large means that we can't pre-paint everything ahead of time and need to repaint during the animation/transition which makes it slow.

Comment 3

[Kartikaya Gupta (email:[e-mail])]

(Speeding up paint, such as with the quantum render effort, is probably the best bet in terms of improving this performance)

Comment 4

[Botond Ballo [:botond]]

(In reply to away[Nov24,Dec5) Kartikaya Gupta (email:[e-mail]) from comment #2)
> I'm not sure if there's much we can do here. The fact that the elements are
> large means that we can't pre-paint everything ahead of time and need to
> repaint during the animation/transition which makes it slow.

We can do better. In bug 1100357, we are implementing partial pre-rendering of large animated content (think rendering a "displayport" of the content rather than just the "viewport") so it can still be async-animated.

Comment 5

[Hiroyuki Ikezoe (:hiro)]

Unfortunately, the site now uses margin-left and left transitions instead of transform. :/

Comment 6

[Hiroyuki Ikezoe (:hiro)]

Dropping the dependency on bug 1100357 since the site no longer uses transform animations.

Comment 7

[BMO Automation]

We have completed our launch of our new Firefox on Android. The development of the new versions use GitHub for issue tracking. If the bug report still reproduces in a current version of [Firefox on Android nightly](https://play.google.com/store/apps/details?id=org.mozilla.fenix) an issue can be reported at the [Fenix GitHub project](https://github.com/mozilla-mobile/fenix/). If you want to discuss your report please use [Mozilla's chat](https://wiki.mozilla.org/Matrix#Connect_to_Matrix) server https://chat.mozilla.org and join the [#fenix](https://chat.mozilla.org/#/room/#fenix:mozilla.org) channel.