527762 - CPU maxed out by fill="freeze" after the active duration has ended

Status: RESOLVED FIXED

(Core :: SVG, defect)

Description

[Jonathan Watt [:jwatt]]

I'm seeing the CPU maxed out constantly by SMIL when fill="freeze", even after the active duration has ended. I'll attach a testcase.

There are probably two fixes that are needed here.

 1) Don't resample a frozen animation after it's been frozen

 2) Don't tell elements that they have changed when the animated value
    has not changed since the last sample

Comment 1

[Jonathan Watt [:jwatt]]

Attachment: simple testcase that makes out the CPU

Comment 2

[Jonathan Watt [:jwatt]]

I threw the filter in there just to make the invalidation more expensive so that it's noticeable that we just keep on invalidating the rect continuously.

Comment 3

[Brian Birtles (:birtles)]

(In reply to comment #0)
>  1) Don't resample a frozen animation after it's been frozen

It's supposed to do that already but I think Daniel's commented that bit out until we add HasChangedTarget. See:

http://mxr.mozilla.org/mozilla-central/source/content/smil/nsSMILCompositor.cpp#153

Also, if there are any timing model related issues here then I'd rather just mark it dependent on bug 474743 since that changes the timing model a lot.

>  2) Don't tell elements that they have changed when the animated value
>     has not changed since the last sample

Yeah, that's good too. I think that was always the plan but it doesn't look like we're doing it yet.

Comment 4

[Daniel Holbert [:dholbert]]

(In reply to comment #3)
> (In reply to comment #0)
> >  1) Don't resample a frozen animation after it's been frozen
> 
> It's supposed to do that already but I think Daniel's commented that bit out
> until we add HasChangedTarget.

Bug 533291 will address this part.

Comment 5

[Daniel Holbert [:dholbert]]

Just landed Bug 533291, which fixes this bug in my debug build.  (CPU usage goes back to normal after animation completes.)

Resolving.

Comment 6

[Jonathan Watt [:jwatt]]

Sweet. :-)