1981364 - 0.31 - 0.28% installer size / installer size (Windows) regression on Mon July 28 2025

Status: RESOLVED WONTFIX

(Firefox :: Installer, defect)

Description

[Treeherder Bug Filer]

Perfherder has detected a build_metrics performance regression from push 747e50133b4ed24da8ad9dcc176d5dc366c9a802. 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)
0.31%	installer size	windows2012-32-shippable	nightly	106,737,510.12 -> 107,070,234.42
0.28%	installer size	win64-nightlyasrelease	nightly nightly-as-release	122,446,061.42 -> 122,788,349.50

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

You can run all of these tests on try with ./mach try perf --alert 46100

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 1968279

Comment 2

[Chris DuPuis]

The increased installer size is expected, as https://bugzilla.mozilla.org/show_bug.cgi?id=1968279 adds a new executable to the installer.