1957006 - 11.99% damp custom.jsdebugger.stepOver.big-bundle.DAMP (Linux) regression on Mon March 17 2025

Status: RESOLVED WONTFIX

(DevTools :: Debugger, defect)

Description

[Treeherder Bug Filer]

Perfherder has detected a devtools performance regression from push 7ce33b38a71b1176dcdfff3e48d75565a51efd71. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

Ratio	Test	Platform	Options	Absolute values (old vs new)
10%	damp custom.jsdebugger.stepInNewSource.big-bundle.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	2,402.63 -> 2,645.69
6%	damp custom.jsdebugger.stepInNewSource.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	2,179.60 -> 2,311.00
3%	damp custom.jsdebugger.stepInNewSource.big-bundle.DAMP	windows11-64-24h2-shippable	e10s fission stylo webrender	1,008.80 -> 1,043.60
3%	damp custom.jsdebugger.stepInNewSource.DAMP	windows11-64-24h2-shippable	e10s fission stylo webrender	867.71 -> 895.57

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
30%	damp custom.jsdebugger.pretty-print.reload-and-pause.DAMP	macosx1470-64-shippable	e10s fission stylo webrender	6,726.90 -> 4,705.58
29%	damp custom.jsdebugger.pretty-print.reload-and-pause.DAMP	windows11-64-24h2-shippable	e10s fission stylo webrender	3,918.09 -> 2,792.60
27%	damp custom.jsdebugger.pretty-print.reload-and-pause.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	9,196.94 -> 6,684.42
12%	damp custom.jsdebugger.stepOver.big-bundle.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	774.25 -> 681.43

Details of the alert can be found in the alert summary, including links to graphs and comparisons for each of the affected tests. Please follow our guide to handling regression bugs and let us know your plans within 3 business days, or the patch(es) may be backed out in accordance with our regression policy.

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 all of these tests on try with ./mach try perf --alert 44409

The following documentation link provides more information about this command.

For more information on performance sheriffing please see our FAQ.

If you have any questions, please do not hesitate to reach out to [e-mail].

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1943945

Comment 3

[Hubert Boma Manilla (:bomsy)]

The regressions on the step in are expected. This moves away from using the babel parser to using codemirror lezer parser.