1305552 - [EME] Add telemetry to track uses of MediaKeySession.generateRequest

Status: RESOLVED FIXED

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

Description

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

In bug 1304207 I added telemetry to track instantiations of EME CDMs. However, some sites (notably the Shaka Player Demo) instantiate CDMs but don't actually use the CDMs. So in order to determine via telemetry whether CDMs are being used, we actually need a new probe which tracks how often the CDMs are used to generate licenses.

Comment 1

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

Attachment: Bug 1305552 - Add telemetry to track uses of MediaKeySession.generateRequest.

This allows us to track how often EME CDMs are used, rather than just created.
The telemetry I added in bug 1304207 is reports whenever a CDM is created, but
some sites, such as the Shaka Player demo site, create CDMs without using them,
so that telemetry isn't a great measure in helping us detect when CDMs aren't
being used. Whereas the telemetry added here will report when the CDMs are used
to negotiate a license, i.e. when the CDMs are actually being used.

Review commit: https://reviewboard.mozilla.org/r/81264/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/81264/

Comment 2

[Gerald Squelart (he/him) (not at Mozilla since 2022-09-15)]

Comment on attachment 8795095 [details]
Bug 1305552 - Add telemetry to track uses of MediaKeySession.generateRequest.

https://reviewboard.mozilla.org/r/81264/#review79872

Comment 3

[François Marier [:francois]]

Comment on attachment 8795095 [details]
Bug 1305552 - Add telemetry to track uses of MediaKeySession.generateRequest.

https://reviewboard.mozilla.org/r/81264/#review80064

datareview+

Comment 4

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

Will need to uplift this too.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/3bbbac2f6775
Add telemetry to track uses of MediaKeySession.generateRequest. r=francois,gerald

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

I had to back this out for android build failures like https://treeherder.mozilla.org/logviewer.html#?job_id=4081551&repo=autoland

https://hg.mozilla.org/integration/autoland/rev/680d0872696f

Comment 7

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

https://treeherder.mozilla.org/#/jobs?repo=try&revision=5aebdd0e41d4

Comment 8

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

Not just android, for the record, looks like all platforms.

Comment 9

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

https://treeherder.mozilla.org/#/jobs?repo=try&revision=f546d3577691

Comment 10

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

https://hg.mozilla.org/integration/mozilla-inbound/rev/0ef0d8d926014e14bde37d3a65e53e57085c0b44
Bug 1305552 - Add telemetry to track uses of MediaKeySession.generateRequest. r=francois,gerald

Comment 11

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/0ef0d8d92601

Comment 12

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

Comment on attachment 8795095 [details]
Bug 1305552 - Add telemetry to track uses of MediaKeySession.generateRequest.

Approval Request Comment
[Feature/regressing bug #]: EME
[User impact if declined]: To help facilitate making a decision as to when we can remove Adobe EME from Firefox, we'd like to know how often the Adobe CDM is used for EME. The previous telemetry I added in bug 1304207 wasn't precise enough to help with that. This telemetry is more accurate.
[Describe test coverage new/current, TreeHerder]: We have lots of EME tests.
[Risks and why]: Low; we're just adding telemetry.
[String/UUID change made/needed]: None.

Comment 13

[Ritu Kothari (:ritu) (Inactive, please n-i to RyanVM, jcristau, or pascal)]

Hi Chris, does the data from this new probe looking good on Nightly52?

Comment 14

[Ritu Kothari (:ritu) (Inactive, please n-i to RyanVM, jcristau, or pascal)]

Comment on attachment 8795095 [details]
Bug 1305552 - Add telemetry to track uses of MediaKeySession.generateRequest.

New CDM usage telemetry probe, Aurora51+, Beta50+

Comment 15

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

This doesn't apply cleanly to beta, can we get a rebased patch?

Comment 16

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/releases/mozilla-aurora/rev/287ec2c7587c

Comment 17

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

(In reply to Ritu Kothari (:ritu) from comment #13)
> Hi Chris, does the data from this new probe looking good on Nightly52?

Yes, the data reported by the probe is matching my expectations.

Comment 18

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

https://hg.mozilla.org/releases/mozilla-beta/rev/f3362d645d5e