1668006 - 3.24 - 7.16% displaylist_mutate (linux64-shippable-qr) regression on push a2cae7f0e3ff5fe563dc604dd70028ea9cf451a8 (Thu September 24 2020)

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect)

Description

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

Perfherder has detected a talos performance regression from push a2cae7f0e3ff5fe563dc604dd70028ea9cf451a8. As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

7% displaylist_mutate linux64-shippable-qr opt e10s stylo 2,762.93 -> 2,960.64
3% displaylist_mutate linux64-shippable-qr opt e10s stylo 2,957.25 -> 3,053.17

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

[Glenn Watson [:gw]]

I can see what is causing this, after reviewing which sub-tests regressed - will work on a fix this week.

Comment 2

[Glenn Watson [:gw]]

Attachment: Bug 1668006 - Add a last used cache for hit-test clip items.

This fixes a talos regression in the inactive and flattened
displaylist_mutate tests.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/d1efb31f500b
Add a last used cache for hit-test clip items. r=kvark

Comment 4

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/d1efb31f500b

Comment 5

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

Set release status flags based on info from the regressing bug 1666641

Comment 6

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

== Change summary for alert #27103 (as of Wed, 30 Sep 2020 17:49:31 GMT) ==

Improvements:

5% displaylist_mutate windows10-64-shippable-qr opt e10s stylo 2,855.58 -> 2,718.86
5% displaylist_mutate linux64-shippable-qr opt e10s stylo 3,041.60 -> 2,899.83

For up to date results, see: https://treeherder.mozilla.org/perf.html#/alerts?id=27103