Bugzilla

I just tried the http://tests.themasta.com/load-never-finishes.php page and the numbers I'm seeing in about:processes match pretty well what Henrik reported in comment 21 for the "with webrender" case.

Here's a profile of it: https://share.firefox.dev/3rcXfyT Is there anything that looks like it could be optimized here?

Then I wondered if we stop running the animation went the loading tab is scrolled away in the tab bar. Here is a profile of me opening many new tabs until the permanently loading tab scrolls away: https://share.firefox.dev/3uvkJkN
I see we keep having MozAfterPaint events sent to the parent process main thread and the Compositor track has many "EmptyTransaction" markers (but the SampleAnimation markers stop when the animated element is off screen). Is this expected or should we avoid some of this work?

I wonder if there are also things that should be done on the front-end: should the animation be stopped after some time (maybe a minute or two?) and replaced with a still icon? Should the front-end attempt to detect the scrolled-away tabs and have a CSS rule to stop entirely the animation on them?

I just tried the http://tests.themasta.com/load-never-finishes.php page and the numbers I'm seeing in about:processes match pretty well what Henrik reported in comment 21 for the "with webrender" case.

Here's a profile of it: https://share.firefox.dev/3rcXfyT Is there anything that looks like it could be optimized here?

Then I wondered if we stop running the animation when the loading tab is scrolled away in the tab bar. Here is a profile of me opening many new tabs until the permanently loading tab scrolls away: https://share.firefox.dev/3uvkJkN
I see we keep having MozAfterPaint events sent to the parent process main thread and the Compositor track has many "EmptyTransaction" markers (but the SampleAnimation markers stop when the animated element is off screen). Is this expected or should we avoid some of this work?

I wonder if there are also things that should be done on the front-end: should the animation be stopped after some time (maybe a minute or two?) and replaced with a still icon? Should the front-end attempt to detect the scrolled-away tabs and have a CSS rule to stop entirely the animation on them?