1929003 - Make the DevTools tracer button use the native profiler pipeline

Status: RESOLVED FIXED

(DevTools :: Debugger, enhancement)

Description

[Alexandre Poirot [:ochameau]]

Bug 1911021 reverted back the tracer controlled from DevTools to manually generate the profile via Spidermonkey hooks.

We should make the DevTools tracer icon use the new native profiler pipeline to gather tracing profiles.

Comment 1

[Alexandre Poirot [:ochameau]]

Attachment: Bug 1929003 - [devtools] Use native profiler to collect JS Traces from DevTools.

Stop manually crafting the profiler data by using SpiderMonkey hooks.
Instead, use the profiler native pipeline to do the collection.

This still relies on JSTracer class in order to trigger the record on next interaction or page load.
One caveat is that it starts the profiler from the content process, which prevents recording screenshots correctly.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/cd1c6516429a
[devtools] Use native profiler to collect JS Traces from DevTools. r=dthayer

Comment 3

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/cd1c6516429a

Comment 4

[Nicolas Chevobbe [:nchevobbe]]

Perfherder has detected a devtools performance change from push 1bb3c36a15c39849a61394f997225808d6c215b5.

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
45%	damp jstracer.profiler-recording-performance.DAMP	macosx1015-64-shippable-qr	e10s fission stylo webrender	519.44 -> 286.36
37%	damp jstracer.profiler-recording-performance.DAMP	windows11-64-shippable-qr	e10s fission stylo webrender	250.19 -> 156.97
29%	damp jstracer.profiler-recording-performance.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	710.70 -> 506.90

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests.

If you need the profiling jobs you can trigger them yourself from treeherder job view or ask a sheriff to do that for you.

You can run these tests on try with ./mach try perf --alert 42500

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