1711420 - Audit and fix profiler markers / thread registration for playback scenario

Status: NEW

(Core :: Audio/Video: Playback, enhancement)

Description

[Paul Adenot (:padenot)]

See https://share.firefox.dev/3ygC4hf and https://share.firefox.dev/3eS7dQn, which are two different profiles of someone trying to help us by sharing a performance profile of a 4k video that isn't playing smoothly or at all in Firefox, whereas it works on other browsers on the same machine.

I can't find any decode calls in the profile, so we don't know what's going on. We know there are frames that are discarded, and that decode is bursty, that's about it. Generally we can't understand what's going on.

Immediate things we need:

• Markers for video decode start/end, init/flush. Stack sampling is not enough, we want to gauge both the performance and the variation in performance
• RDD process in Media profile
• register the worker threads in ffvpx (this is apparently vp9 decoding)

Comment 1

[Paul Adenot (:padenot)]

It seems like the RDD process lane wasn't shown, and so it hasn't been uploaded, this is a problem. Maybe we want to force it enabled when using the Media profiler preset.