Bug 172343 – Speedometer 2.0: Elem test isn't updating DOM during the measurement

• Component: Tools / Tests
• Status: RESOLVED FIXED

[Ryosuke Niwa]

Elm has its own work queue which gets executed in setTimeout and requestAnimationFrame.
We need to manually trigger these functions to make a meaningful measurement.

[Ryosuke Niwa]

Created attachment 310618 [details]
Fixes the Elm test

[Ryosuke Niwa]

Another approach is to wrap each callback to rAF and measure the time spent in each rAF and wait for all rAF callbacks to be done. Unfortunately, this would require quite a bit of reworking in the way Speedometer works, and this is something I thought about it very carefully during the initial development of the benchmark and decided not go with since it really increases the complexity of the benchmark, and makes it really hard to get traces, etc...

[Ryosuke Niwa]

Created attachment 310634 [details]
Removed superflous call to console.log

[Antti Koivisto]

Comment on attachment 310634 [details]
Removed superflous call to console.log

View in context: https://bugs.webkit.org/attachment.cgi?id=310634&action=review

> PerformanceTests/Speedometer/resources/tests.js:421
> +    const callbacks = contentWindow.rAFCallbackList;
> +    var i = 0;

Why 'const' but not 'let'?

[Ryosuke Niwa]

Comment on attachment 310634 [details]
Removed superflous call to console.log

View in context: https://bugs.webkit.org/attachment.cgi?id=310634&action=review

>> PerformanceTests/Speedometer/resources/tests.js:421
>> +    var i = 0;
> 
> Why 'const' but not 'let'?

Oops, would use var

[Ryosuke Niwa]

Committed r217119: <http://trac.webkit.org/changeset/217119>