1683903 - 2.2 - 2.82% bbc LastVisualChange (android-hw-g5-7-0-arm7-api-16-shippable) regression on push 03e46a1ed9c18dfee6002d37044d4a052cdeb956 (Tue December 15 2020)

Status: RESOLVED FIXED

(Core :: JavaScript: GC, defect)

Description

[Florin Strugariu [:Bebe]]

Perfherder has detected a browsertime performance regression from push 03e46a1ed9c18dfee6002d37044d4a052cdeb956. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

Ratio	Suite	Test	Platform	Options	Absolute values (old vs new)
3%	bbc	LastVisualChange	android-hw-g5-7-0-arm7-api-16-shippable	nocondprof warm webrender	2,976.46 -> 3,060.25
2%	bbc	LastVisualChange	android-hw-g5-7-0-arm7-api-16-shippable	nocondprof warm webrender	2,996.08 -> 3,062.08

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 offending patch(es) will be backed out in accordance with our regression policy.

For more information on performance sheriffing please see our FAQ.

Comment 1

[Jon Coppeard (:jonco)]

This may be the same issue as bug 1683894. Let's see if that fixes it.

Comment 2

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

Set release status flags based on info from the regressing bug 1677765

Comment 3

[Jon Coppeard (:jonco)]

This has improved again to better than previous level. This happened a little before the fix for bug 1683894 landed so I'm not sure exactly what happened here, but the regression has gone away at least.