1864789 - 20% regression on AWFY-Downmix without resampling (Stereo -> Mono) around 9Nov2023

Status: RESOLVED FIXED

(Core :: Audio/Video: MediaStreamGraph, defect)

Description

[Mayank Bansal]

Look at https://treeherder.mozilla.org/perfherder/graphs?highlightAlerts=1&highlightChangelogData=1&highlightCommonAlerts=0&selected=4184185,1791369081&series=mozilla-central,4184353,1,13&series=autoland,4184185,1,13&timerange=5184000&zoom=1699468062099,1699650245450,24.980511756504278,59.65285520775645

Regression range:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=938e6fc607623834483a5ab95019520814f10ee8&tochange=d3aff5d6c69730c6f26eb54b7e24fdd203480069

Potential regressors: bug 1863799

Comment 1

[Karl Tomlinson (:karlt)]

Thanks. I might be able to narrow down exactly what caused the change.
Sometimes it might just be inlining decisions, but perhaps there's something i've overlooked.

Today's change in https://hg.mozilla.org/integration/autoland/rev/3d878e45d5c5 might be what more than won back the regression.

https://treeherder.mozilla.org/perfherder/graphs?highlightAlerts=1&highlightChangelogData=1&highlightCommonAlerts=0&series=mozilla-central,4184353,1,13&series=autoland,4184185,1,13&timerange=5184000&zoom=1699468062099,1700056878141,23.199424894356426,59.652855207756474

Comment 2

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

Set release status flags based on info from the regressing bug 1863799

Comment 3

[Karl Tomlinson (:karlt)]

The release-mode bounds assertions in Spans indexed element access might have been involved here, in which case turning the loops inside out may have been what resolved this.

S4 because this has apparently already been fixed. Some investigation could confirm suspicions from which we might learn lessons about future use of Spans.

Comment 4

[Ryan VanderMeulen [:RyanVM]]

Closing this out since AFAICT there's no active regression to track here at this point. Don't let that stop whatever follow-up investigation you were planning to do in comment 3, though :-)