1907888 - DevTools performance regression

Status: RESOLVED DUPLICATE of bug 1907883

(Core :: IPC, defect)

Description

[Nicolas Chevobbe [:nchevobbe][PTO - back on October 21]]

Perfherder has detected a devtools performance change from push 3a566759c7629cffbe61577a33d6bc66c22455db.

Regressions:

Ratio	Test	Platform	Options	Absolute values (old vs new)
28%	damp source-map.SourceMapGenerator-toString.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	369.61 -> 473.41
24%	damp source-map.SourceMapGenerator-toString.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	366.27 -> 452.82
21%	damp source-map.SourceMapGenerator-toString.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	387.33 -> 469.55
21%	damp custom.jsdebugger.open-large-minified-file.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	1,097.45 -> 1,329.23
21%	damp complicated.styleeditor.open.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	411.84 -> 497.65
20%	damp complicated.styleeditor.open.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	418.07 -> 501.98
16%	damp source-map.eachMapping.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	298.94 -> 347.10
13%	damp console.log-in-loop-content-process-nodelist	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	934.96 -> 1,060.33
13%	damp source-map.originalPositionFor.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	328.87 -> 371.02
12%	damp console.log-in-loop-content-process-nodelist	linux1804-64-shippable-qr	e10s fission stylo webrender	940.92 -> 1,052.90
...	...	...	...	...
3%	damp console.log-in-loop-content-process-longstring	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	113.02 -> 116.96
3%	damp custom.jsdebugger.pretty-print.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	2,582.47 -> 2,661.95
3%	damp console.content-process-bulklog	linux1804-64-shippable-qr	e10s fission stylo webrender	526.13 -> 541.84
2%	damp console.bulklog	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	873.43 -> 893.15
2%	damp console.objectexpand	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	425.15 -> 434.64

Improvements:

Ratio	Test	Platform	Options	Absolute values (old vs new)
22%	damp complicated.webconsole.close.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	17.75 -> 13.93
14%	damp custom.inspector.open.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	390.07 -> 335.65
14%	damp custom.inspector.open.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	389.74 -> 336.66
13%	damp cold.accessibility.open.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	353.25 -> 306.46
12%	damp screenshot.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender	789.48 -> 692.20
...	...	...	...	...
7%	damp custom.netmonitor.open.DAMP	linux1804-64-shippable-qr	e10s fission stylo webrender-sw	195.79 -> 181.66

As author of one of the patches included in that push, we need your help to address this regression.
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 patch(es) may be backed out in accordance with our regression policy.

If you need the profiling jobs you can trigger them yourself from treeherder job view or ask a sheriff to do that for you.

You can run these tests on try with ./mach try perf --alert 1154

For more information on performance sheriffing please see our FAQ.

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Note that this might be caused by Bug 1896054 (and not Bug 1874689), but those were pushed at the same time, so I'm picking the last one (plus there's comments on Bug 1874689 suggesting it did impacted other perf tests).

Comment 1

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

Set release status flags based on info from the regressing bug 1874689

:gcp, since you are the author of the regressor, bug 1874689, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 2

[:gerard-majax]

Very much likely the same cause as bug 1907883