1959948 - 16.06 - 13.58% damp console.log-in-loop-content-process-typedarray / damp console.log-in-loop-content-process-typedarray + 2 more (Linux, OSX, Windows) regression on Wed March 26 2025

Status: RESOLVED FIXED

(DevTools :: Debugger, defect)

Description

[Treeherder Bug Filer]

Perfherder has detected a devtools performance regression from push f0268a9cb2ff5e9d15f9a726b89c6acee5a3dd07. As author of one of the patches included in that push, we need your help to address this regression.

Please acknowledge, and begin investigating this alert within 3 business days, or the patch(es) may be backed out in accordance with our regression policy. Our guide to handling regression bugs has information about how you can proceed with this investigation.

If you have any questions or need any help with the investigation, please reach out to [e-mail]. Alternatively, you can find help on Slack by joining #perf-help, and on Matrix you can find help by joining #perftest.

Regressions:

Ratio	Test	Platform	Options	Absolute values (old vs new)
16%	damp console.log-in-loop-content-process-typedarray	windows11-64-24h2-shippable	e10s fission stylo webrender	67.42 -> 78.25
15%	damp console.log-in-loop-content-process-typedarray	macosx1470-64-shippable	e10s fission stylo webrender	144.79 -> 166.19
14%	damp console.log-in-loop-content-process-typedarray	linux1804-64-shippable-qr	e10s fission stylo webrender	198.35 -> 225.76
14%	damp console.log-in-loop-content-process-typedarray	linux1804-64-shippable-qr	e10s fission stylo webrender	199.00 -> 226.03

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
4%	damp browser-toolbox.close-process.DAMP	windows11-64-24h2-shippable	e10s fission stylo webrender	51.81 -> 49.61

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 [e-mail] to do that for you.

You can run all of these tests on try with ./mach try perf --alert 44631

The following documentation link provides more information about this command.

Comment 1

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

Set release status flags based on info from the regressing bug 1956197

Comment 2

[Nicolas Chevobbe [:nchevobbe]]

Attachment: Bug 1959948 - [devtools] Avoid calling createValueGrip on non-bigint typed array items. r=#devtools.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a87e94a7552e
[devtools] Avoid calling createValueGrip on non-bigint typed array items. r=devtools-reviewers,ochameau.

Comment 4

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/a87e94a7552e

Comment 5

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

The patch landed in nightly and beta is affected.
:nchevobbe, is this bug important enough to require an uplift?

• If yes, please nominate the patch for beta approval.
  • See https://wiki.mozilla.org/Release_Management/Requesting_an_Uplift for documentation on how to request an uplift.
• If no, please set status-firefox138 to wontfix.

For more information, please visit BugBot documentation.

Comment 6

[Nicolas Chevobbe [:nchevobbe]]

Attachment: Bug 1959948 - [devtools] Avoid calling createValueGrip on non-bigint typed array items. r=#devtools.

Original Revision: https://phabricator.services.mozilla.com/D245376

Comment 7

[Phabricator Automation]

beta Uplift Approval Request

• User impact if declined: ~15% performance regression on console.log with typed arrays
• Code covered by automated testing: no
• Fix verified in Nightly: no
• Needs manual QE test: no
• Steps to reproduce for manual QE testing: -
• Risk associated with taking this patch: low
• Explanation of risk level: devtools only, feature is covered by tests
• String changes made/needed: -
• Is Android affected?: yes

Comment 8

[Pulsebot]

https://hg.mozilla.org/releases/mozilla-beta/rev/bcaa5d0403bc