1677771 - 5.02 - 15.22% Explicit Memory / Heap Unclassified / Resident Memory (linux1804-64-shippable-qr, macosx1014-64-shippable-qr) regression on push 6319f8438a3a47519479f0c96e6d69b420652d02 (Fri November 13 2020)

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect)

Description

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

Perfherder has detected a awsy performance regression from push 6319f8438a3a47519479f0c96e6d69b420652d02. 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)
15%	Heap Unclassified		linux1804-64-shippable-qr		258,750,465.88 -> 298,144,946.46
13%	Resident Memory		macosx1014-64-shippable-qr		715,788,069.91 -> 809,697,060.05
9%	Explicit Memory		linux1804-64-shippable-qr		520,974,186.75 -> 569,263,778.36
5%	Resident Memory		linux1804-64-shippable-qr		987,463,656.99 -> 1,037,043,978.88

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 1674443

Comment 2

[Ryan VanderMeulen [:RyanVM]]

Fixed by backout for 84.
https://hg.mozilla.org/releases/mozilla-beta/rev/829d402760bc

Comment 3

[Nicolas Silva [:nical]]

I'm bisecting the patches. They aren't supposed to change behavior much so once I know which one regressed things it shouldn't be too hard to spot the bug that ended caused the memory regression.

Comment 4

[Nicolas Silva [:nical]]

The bug is in https://hg.mozilla.org/integration/autoland/rev/6319f8438a3a

There's a loop over textures that tries to allocate a rectangle in one of them except that it doesn't stop looping after it's managed to allocate from one of them. Oops.

Comment 5

[Nicolas Silva [:nical]]

Attachment: Bug 1677771 - Fix the texture cache allocating rectangles multiple times. r=jnicol

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/64036a891adc
Fix the texture cache allocating rectangles multiple times. r=jnicol

Comment 7

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/64036a891adc

Comment 8

[Andra Esanu (needinfo me)]

== Change summary for alert #27852 (as of Tue, 24 Nov 2020 14:16:42 GMT) ==

Improvements:

Ratio	Suite	Test	Platform	Options	Absolute values (old vs new)
14%	Heap Unclassified		linux1804-64-shippable-qr		297,486,328.91 -> 254,553,702.44
12%	Resident Memory		macosx1014-64-shippable-qr		806,530,281.75 -> 708,353,712.96
10%	Explicit Memory		linux1804-64-shippable-qr		570,135,731.39 -> 512,560,465.39
10%	Resident Memory		macosx1014-64-shippable-qr		795,757,452.96 -> 716,913,380.54
6%	Resident Memory		linux1804-64-shippable-qr		1,031,910,890.14 -> 972,001,736.74
2%	JS		linux1804-64-shippable		79,527,719.62 -> 77,618,713.52

For up to date results, see: https://treeherder.mozilla.org/perfherder/alerts?id=27852