1747075 - 16.89 - 6.03% perf_reftest coalesce-2.html / perf_reftest coalesce-1.html + 6 more (OSX, Windows) regression on Sat December 18 2021

Status: RESOLVED WORKSFORME

(Core :: CSS Parsing and Computation, defect)

Description

[Andra Esanu (needinfo me)]

Perfherder has detected a talos performance regression from push b050582bc984b158bc89a62f41466d46475c8450. 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)
17%	perf_reftest coalesce-2.html	windows10-64-shippable-qr	e10s fission stylo webrender	23.23 -> 27.15
15%	perf_reftest coalesce-2.html	macosx1015-64-shippable-qr	e10s fission stylo webrender	24.52 -> 28.13
14%	perf_reftest coalesce-2.html	macosx1015-64-shippable-qr	e10s stylo webrender-sw	25.44 -> 28.97
11%	perf_reftest coalesce-2.html	macosx1014-64-shippable-qr	e10s stylo webrender	37.09 -> 41.29
11%	perf_reftest coalesce-2.html	macosx1014-64-shippable-qr	e10s stylo webrender-sw	37.16 -> 41.24
11%	perf_reftest coalesce-2.html	macosx1014-64-shippable-qr	e10s fission stylo webrender	39.00 -> 43.10
6%	perf_reftest coalesce-1.html	macosx1015-64-shippable-qr	e10s stylo webrender	62.36 -> 66.23
6%	perf_reftest coalesce-1.html	macosx1015-64-shippable-qr	e10s stylo webrender-sw	62.51 -> 66.28

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 1744102

Comment 2

[Emilio Cobos Álvarez [:emilio]]

Let's see if bug 1747037 fixes this.

Comment 3

[Ryan VanderMeulen [:RyanVM]]

Not seeing any obvious improvements in the graphs after that landed.

Comment 4

[Ryan VanderMeulen [:RyanVM]]

Per discussion with Emilio, wontfix for 97 but leaving the bug open for now for future investigation.

Comment 5

[Greg Mierzwinski [:sparky]]

Hi :emilio, do you think it still makes sense to keep this regression bug open? Something to note is that we are migrating the osx tests from 10.15 to 14.70 in the next month so it may no longer be reproducible in the future. Windows 10 tests are also no longer available.

I took a look at the current data for the regressing tests, and it seems to be in the pre-regression range now: https://treeherder.mozilla.org/perfherder/graphs?highlightAlerts=1&highlightChangelogData=1&highlightCommonAlerts=0&replicates=0&series=mozilla-central,4773827,1,1&timerange=31536000&zoom=1700613614406,1732287354022,2.9813440372242517,38.757344037224286

Comment 6

[Emilio Cobos Álvarez [:emilio]]

Yeah I don't think we're going back to custom containers, and these tests are a bit noisy, but yeah it seems they are better now...