827277 - CSS3 animations take a lot of CPU

Status: NEW

(Core :: Layout, defect)

Description

[Julien Wajsberg [:julienw]]

Attachment: testcase

STR:
* watch Firefox CPU usage
* open the attachment
* watch Firefox CPU usage

Expected:
* it should be a little higher

Actual:
* it is a lot higher (around 40% more on a recent i7 cpu)

I originally found this on a B2G device, b2g's process takes between 30 and 40% CPU on this page.

Comment 1

[Julien Wajsberg [:julienw]]

Chrome takes ~10% on the same page/same PC.

Comment 2

[Alex Keybl [:akeybl]]

Until this is a partner required perf issue, no need to track.

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

What happens with this testcase on B2G (which as OMTA enabled) should be very different from what happens on desktop.

Profiles would be useful on either though; not sure which this bug report should focus on.

Comment 4

[Bobby Chien]

Julien, do you know this issue is still exist or not? Thanks.

Comment 5

[Julien Wajsberg [:julienw]]

On a Flame it takes 22 and 45%.
And actually, same on Aries, but somewhat more stable: between 28 and 37%.

While I'm on it, I can take a profile from the Flame.

Comment 6

[Julien Wajsberg [:julienw]]

Here: http://people.mozilla.org/~bgirard/cleopatra/#report=9302997d4be06bb1e826090e963409172efb9715

If it's not useful enough, I'll let Bobby do it ;)