Closed Bug 1187760 Opened 6 years ago Closed 6 years ago

[EME] Add telemetry to report requestMediaKeySystemAccess latency

Categories

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

defect

Tracking

()

RESOLVED FIXED
mozilla44
Tracking Status
firefox44 --- fixed

People

(Reporter: cpearce, Assigned: cpearce)

References

(Blocks 1 open bug)

Details

Attachments

(1 file)

If we had telemetry to report how long navigator.requestMediaKeySystemAccess() takes, we'd know whether our Adobe CDM downloads are timing out or not.
Component: Video/Audio: Recording → Video/Audio: Playback
Netflix have started setting a timeout of about 2 seconds when they call navigator.requestMediaKeySystemAccess(), and if we don't resolve before the timeout expires, they navigate (which causes our navigator.requestMediaKeySystemAccess() promise to reject) and throw up a "Install SilverLight" page.

So it doesn't make sense to report telemetry for the elapsed time taken to fulfil the promise as a means to determine whether the CDM download is working, since Netflix is canceling our promise.
Status: NEW → RESOLVED
Closed: 6 years ago
Resolution: --- → WONTFIX
Actually, this is useful, as if it takes us longer than one second to resolve the navigator.requestMediaKeySystemAccess() promise, Netflix will fallback to Silverlight, and we don't want that.

So this telemetry is a way to track our fallback-to-Silverlight rate.
Status: RESOLVED → REOPENED
Resolution: WONTFIX → ---
Add telemetry to report how long it takes us to resolve or reject the promise returned by navigator.requestMediaKeySystemAccess().

This enables us to track how often Netflix falls back to Silverlight, since they do so if either the navigator.requestMediaKeySystemAccess() rejects, or takes more than 1 second to resolve.

opt-out telemetry, so r? vladan.
Assignee: nobody → cpearce
Status: REOPENED → ASSIGNED
Attachment #8664020 - Flags: review?(vladan.bugzilla)
Attachment #8664020 - Flags: review?(edwin)
Comment on attachment 8664020 [details] [diff] [review]
Patch: Add telemetry to record navigator.requestMediaKeySystemAccess latency.

Review of attachment 8664020 [details] [diff] [review]:
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::: toolkit/components/telemetry/Histograms.json
@@ +9376,5 @@
> +    "kind": "exponential",
> +    "high": "60000",
> +    "n_buckets": 60,
> +    "releaseChannelCollection": "opt-out",
> +    "description": "Time spent waiting for a navigator.requestMediaKeySystemAccess call to succeed."

indicate time units in the description or the histogram name (e.g. .._LATENCY_MS)
Attachment #8664020 - Flags: review?(vladan.bugzilla) → review+
Uplift needed.
Flags: needinfo?(cpearce)
https://hg.mozilla.org/mozilla-central/rev/71b0991c0f1d
Status: ASSIGNED → RESOLVED
Closed: 6 years ago6 years ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla44
We can get by without uplift I think.
Flags: needinfo?(cpearce)
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