1255834 - Animation on https://heroesofparagon.com/ isn't as smooth as before and uses more CPU

Status: RESOLVED WONTFIX

(Core :: Graphics: Layers, defect)

Description

[Marco Castelluccio [:marco]]

mozregression pointed me to bug 1241832.

Interestingly, this isn't happening in my Firefox profile, but is happening in a clean profile (probably because AdBlock is blocking some elements, e.g. the Facebook widget).

Comment 1

[Marco Castelluccio [:marco]]

Attachment: before.png

Comment 2

[Marco Castelluccio [:marco]]

Attachment: after.png

Comment 3

[Marco Castelluccio [:marco]]

https://cleopatra.io/#report=54efcec2622807f8b9af08465b0fd7ffdb66a1a2

Comment 4

[Marco Castelluccio [:marco]]

Attachment: aboutsupport.txt

Comment 5

[Marco Castelluccio [:marco]]

The profile from comment 3 is taken from a *bad* build, this is from a *good* one: https://cleopatra.io/#report=b5aac709d01c55e3efe9cf2d6e27fb35173e7bf4

Comment 6

[Marco Castelluccio [:marco]]

Attachment: aboutsupport_good.txt

This is the about:support from the *good* build (the other one was from the *bad* one).

Comment 7

[Edwin Flores [inactive from 2016-12-01] [:eflores] [:edwin]]

Looks like this is from turning off XRender.

The "after" profile isn't using XRender, and the compositor is spending 95% of its time in |CompositorParent::Composite|, 80% of which is in |_moz_pixman_image_composite|.

The "before" has XRender on and |CompositorParent::Composite| barely shows up on the profile.

ni?lee to confirm, and because he loves XRender sadness.

Comment 8

[Edwin Flores [inactive from 2016-12-01] [:eflores] [:edwin]]

This will likely get faster after bug 1255281 (probably still not as fast as it was, though...).

Comment 9

[Lee Salzman [:lsalzman]]

(In reply to Edwin Flores [:eflores] [:edwin] from comment #8)
> This will likely get faster after bug 1255281 (probably still not as fast as
> it was, though...).

Confirmed. We were falling off the fast path in pixman again. The added BGRX->BGRA fast-path is where we spend most of our time now. Not sure if it made it's way into nightlies yet, but pulling from central and building that way at least should have it in.

I'm not sure there's more that we can do for this case than that, though.

Comment 10

[Marco Castelluccio [:marco]]

Yeah, it doesn't seem to have helped much.

Comment 11

[Milan Sreckovic [:milan] (needinfo for best results)]

If we don't manage to figure this one out, chances are we will just live with it, not having xrender is that important.  Parking with me until we sort this out.

Comment 12

[Milan Sreckovic [:milan] (needinfo for best results)]

We're going to stick with not having xrender.