[shadowgovt]

What would the alternative be?

(Worth noting: Google Hangouts predates WebRTC. I think a case can be made that big data collection of real users machine performance in the real world was instrumental for hammering out the last mile issues in Hangouts, which informed WebRTC's design. I'm sure we would have gotten there eventually, my contention is it would have taken longer without concrete metrics about performance).

[refulgentis]

I made this.

  +------------------+
  |   Web Browser    |
  | +--------------+ |
  | |  WebRTC      | |
  | |  Components  | |
  | +------+-------+ |
  |        |         |
  | +------v-------+ |    +---------------+
  | | Browser's    | |    |   Website     |
  | | Internal     | |    | (e.g. Google  |
  | | Telemetry    | |    |  Meet)        |
  | +------+-------+ |    |               |
  |        |         |    |  (No direct   |
  | +------v-------+ |    |   access to   |
  | |  CPU Stats   | |    |   CPU stats)  |
  | |  (Internal)  | |    |               |
  +------------------+    +---------------+
           |
           | WebRTC metrics
           | (including CPU stats as needed)
           v
  +------------------+
  |  Google Servers  |
  | (Collect WebRTC  |
  |    metrics)      |
  +------------------+

Another attempt, in prose:

I am referring to two alternatives to consider:

A) Chrome sends CPU usage metrics, for any WebRTC domain, in C++

B) as described in TFA: JavaScript, running on allow-listed Google sites only, collect CPU usage via a JavaScript web API

There's no need to do B) to launch/improve/instrument WebRTC, in fact, it would be bad to only do B), given WebRTC implementers is a much less biased sample for WebRTC metrics than Google implementers of WebRTC.

I've tried to avoid guessing at what you're missing, but since this has dragged out for a day, I hope you can forgive me for guessing here:

I think you think there's a _C++ metrics API for WebRTC in Chrome-only, no web app access_ that _only collects WebRTC on Google domains_, and from there we can quibble about whether its better to have an unbiased sample or if its Google attempting to be a good citizen via collecting data from Google domains.

That's not the case.

We are discussing a _JavaScript API_ available only to _JavaScript running on Google domains_ to access CPU metrics.

Additional color commentary to further shore up there isn't some WebRTC improvement loop this helps with:

- I worked at Google, and it would be incredibly bizarre to collect metrics for improvements via B) instead of A).

- We can see via the rest of the thread this is utilized _not for metrics_, but for features such as gSuite admins seeing CPU usage metrics on VC, and CPU usage displayed in Meet in a "Having a problem?" section that provides debug info.

[shadowgovt]

I also worked at Google, and this kind of telemetry collection doesn't seem surprising to me at all. I don't know if you are / were familiar with the huge pile of metrics the UIs collect in general (via Analytics). I never worked on anything that was cpu-intense enough to justify this kind of back-channel, but I don't doubt we'd have asked for it if we thought we needed it... And you'd rather have this as an internal Google-to-Google monitor than punch a big security hole open for any arbitrary domain to query.

JS is easier to debug (even with Google's infrastructure), and they have no need of everyone else's videoconference telemetry (which when this was added, would have been, iirc, Flash-based).

I believe the things they learned via this closed loop let Google learn things that informed the WebRTC standard, hence my contention it got us there faster. Unless I've missed something, this API was collecting data since 2008. WebRTC was 3 years later.

I think you've misunderstood my question regarding "What would the alternative be?" I meant what would the alternative be to collecting stats data via a private API only on Google domains when we didn't have a standard for performance collection in browsers? We certainly don't want Google railroading one into the public (with all the security concerns that would entail). And I guess I'm just flat out not surprised that they would have dropped one into their browser to simplify debugging a very performance intensive service that hadn't been supported in the browser outside plugins before. Is your contention that they should have gone the flash route and done a binary as a plug-in, then put telemetry in the binary? Google had (And mostly still has) a very web-centric approach; doing it as a binary wouldn't be in their DNA.