1743387 - 24.03 - 11.83% microsoft PerceptualSpeedIndex / fandom ContentfulSpeedIndex + 2 more (Windows) regression on Thu November 25 2021

Status: RESOLVED WONTFIX

(Testing :: Raptor, defect, P3)

Description

[Alexandru Ionescu (needinfo me) [:alexandrui]]

Perfherder has detected a browsertime performance regression from push 2a6be51563b0582201274f8065694b28ef389b4f. 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)
24%	microsoft PerceptualSpeedIndex	windows10-64-shippable-qr	warm webrender	460.58 -> 571.25
18%	microsoft PerceptualSpeedIndex	windows10-64-shippable-qr	cold webrender	559.75 -> 659.17
15%	microsoft SpeedIndex	windows10-64-shippable-qr	cold webrender	757.04 -> 866.83
12%	fandom ContentfulSpeedIndex	windows10-64-shippable-qr	warm webrender	205.75 -> 230.08

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
24%	microsoft ContentfulSpeedIndex	windows10-64-shippable-qr	warm webrender	495.17 -> 376.33
12%	linkedin FirstVisualChange	macosx1014-64-shippable-qr	warm webrender	481.67 -> 423.33
11%	microsoft loadtime	windows10-64-shippable-qr	warm webrender	299.75 -> 266.79

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

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

Set release status flags based on info from the regressing bug 1734466

Comment 2

[Greg Mierzwinski [:sparky]]

We can accept these changes as a new baseline.