1605084 - 2.59 - 2.65% raptor-tp6-slides-firefox-cold fcp (linux64-shippable-qr) regression on push d39132658a17709b5eb8da68fa811d95b6b62e93 (Wed December 18 2019)

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P2)

Description

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

Raptor has detected a Firefox performance regression from push:

https://hg.mozilla.org/integration/autoland/pushloghtml?changeset=d39132658a17709b5eb8da68fa811d95b6b62e93

As author of one of the patches included in that push, we need your help to address this regression.

Regressions:

3% raptor-tp6-slides-firefox-cold fcp linux64-shippable-qr opt 1,214.25 -> 1,246.42
3% raptor-tp6-slides-firefox-cold fcp linux64-shippable-qr opt 1,214.54 -> 1,246.00

You can find links to graphs and comparison views for each of the above tests at: https://treeherder.mozilla.org/perf.html#/alerts?id=24530

On the page above you can see an alert for each affected platform as well as a link to a graph showing the history of scores for this test. There is also a link to a Treeherder page showing the Raptor jobs in a pushlog format.

To learn more about the regressing test(s) or reproducing them, please see: https://wiki.mozilla.org/TestEngineering/Performance/Raptor

*** Please let us know your plans within 3 business days, or the offending patch(es) will be backed out! ***

Our wiki page outlines the common responses and expectations: https://wiki.mozilla.org/TestEngineering/Performance/Talos/RegressionBugsHandling

Comment 1

[Bert Peers [:bpeers]]

By itself it could be a reasonable trade-off of raw throughput for better latency, however 2 of the 3 tests previously flagged in Bug 1604410 show a 20% regression probably due to this, so I'm asking for back out :( Thanks.

Comment 2

[Florin Strugariu [:Bebe]]

Backout by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a1b9706abf85
Backed out changeset 3badff2b3724 as requested by Bert Peers for causing regressions.

== Change summary for alert #24568 (as of Sat, 21 Dec 2019 01:19:43 GMT) ==

Improvements:

3% raptor-tp6-slides-firefox-cold fcp linux64-shippable-qr opt 1,246.08 -> 1,214.67

For up to date results, see: https://treeherder.mozilla.org/perf.html#/alerts?id=24568