1275028 - Fix VIDEO_DETAILED_DROPPED_FRAMES_PROPORTION histogram

Status: RESOLVED WONTFIX

(Core :: Audio/Video: Playback, defect, P1)

Description

[Georg Fritzsche [:gfritzsche]]

VIDEO_DETAILED_DROPPED_FRAMES_PROPORTION uses the key of the histogram in an odd way:
https://dxr.mozilla.org/mozilla-central/rev/16663eb3dcfa759f25b5e27b101bc79270c156f2/dom/media/MediaFormatReader.cpp#1897

It is build it from "mimetype", "screen resolution", "hardware acceleration enabled", which ends up submitting at least 20k different values (which doesn't seem good or useful, see bug 1275019).
This should have bounding, bucketing and put those into separate measurements.
It also needs proper data collection review, which i don't see on bug 1249706:
https://wiki.mozilla.org/Firefox/Data_Collection

Comment 1

[Chris Pearce [:cpearce (Not reading bugmail)]]

Georg: Sorry this landed without data peer review. I'd neglected to mention that was required before passing off the review in bug 1249706.

We'd better turn VIDEO_DETAILED_DROPPED_FRAMES_PROPORTION off and re-do it. How do we disable it? Can we just remove the telemetry definition from Histograms.js? Can you do something to throw away collected data on the server side to reduce your load?

Comment 2

[Georg Fritzsche [:gfritzsche]]

Roberto is handling the server-side over in bug 1275019 (ignoring this histogram), so that is covered.
Removing the probe from Histograms.json is fine.

Note that we don't really support changing histogram definitions, so when updating or replacing it a different name should be used.

Comment 3

[Chris Pearce [:cpearce (Not reading bugmail)]]

rvtillo: Can we get a list of 20K the submitted values for VIDEO_DETAILED_DROPPED_FRAMES_PROPORTION so that we can figure out a sensible way to bucket them? To be honest, I'd expected maybe a hundred different combinations, not thousands!

Comment 4

[Chris Pearce [:cpearce (Not reading bugmail)]]

georg: bug 1249706 is in Firefox 47. Do we need to back it out of 47 before 47 ships?

Comment 5

[Roberto Agostino Vitillo (:rvitillo)]

Attachment: labels

Here is a dump of nearly 10K labels.

Comment 6

[Georg Fritzsche [:gfritzsche]]

(In reply to Chris Pearce (:cpearce) from comment #4)
> georg: bug 1249706 is in Firefox 47. Do we need to back it out of 47 before
> 47 ships?

This is opt-in and the aggregator is ignoring it now, so it should be fine to leave it given that 47 is in its last two weeks on beta.
But if you don't urgently need the info it would be great to have this disabled on 48+.

Comment 7

[Anthony Jones (:ajones, :kentuckyfriedtakahe, :k17e)]

Change is already backed out.