1470901 - Add telemetry probes for WR-internal metrics

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, enhancement, P2)

Description

[Kartikaya Gupta (email:[e-mail])]

It would be good to add some telemetry probes to record how long scene building and rendering take. However the code is in rust, so either we have to ship the numbers to C++ code and record them from there, or add a rust API to telemetry. The former approach might have perf implications since this code is going to run a lot, we would need to be careful to not accidentally regress perf.

Comment 1

[Kartikaya Gupta (email:[e-mail])]

Attachment: Data collection request

Comment 2

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1470901 - WR patch

Review commit: https://reviewboard.mozilla.org/r/253142/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/253142/

Comment 3

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1470901 - Add telemetry probes for measuring WebRender paint phases.

Review commit: https://reviewboard.mozilla.org/r/253144/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/253144/

Comment 4

[Kartikaya Gupta (email:[e-mail])]

Attachment: Bug 1470901 - Record scene build, scene swap, and render times in telemetry.

Review commit: https://reviewboard.mozilla.org/r/253146/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/253146/

Comment 5

[Chris H-C :chutten]

Comment on attachment 8987866 [details]
Bug 1470901 - Add telemetry probes for measuring WebRender paint phases.

https://reviewboard.mozilla.org/r/253144/#review259782

Correct use of Histograms definitions. Will require Data Collection Review.

["main","gpu"] is a novel pair of processes to be recorded in. I'd expect a "content" in there, or "gpu" only. Neat.

Comment 6

[Kartikaya Gupta (email:[e-mail])]

(In reply to Chris H-C :chutten from comment #5)
> ["main","gpu"] is a novel pair of processes to be recorded in. I'd expect a
> "content" in there, or "gpu" only. Neat.

We only have the gpu process on Windows right now. On other platforms the compositor stuff runs in the main process. Hence I'd like to instrument this in both main (for non-Windows) and gpu (for Windows).

Comment 7

[Sotaro Ikeda [:sotaro]]

Comment on attachment 8987867 [details]
Bug 1470901 - Record scene build, scene swap, and render times in telemetry.

https://reviewboard.mozilla.org/r/253146/#review259892

Comment 8

[François Marier [:francois]]

Comment on attachment 8987861 [details]
Data collection request

1) Is there or will there be **documentation** that describes the schema for the ultimate data set available publicly, complete and accurate?

Yes, in Histograms.json.

2) Is there a control mechanism that allows the user to turn the data collection on and off?

Yes, telemetry setting.

3) If the request is for permanent data collection, is there someone who will monitor the data over time?**

Yes, :kats.

4) Using the **[category system of data types](https://wiki.mozilla.org/Firefox/Data_Collection)** on the Mozilla wiki, what collection type of data do the requested measurements fall under?  **

Category 1.

5) Is the data collection request for default-on or default-off?

Default ON, only in pre-release channels.

6) Does the instrumentation include the addition of **any *new* identifiers** (whether anonymous or otherwise; e.g., username, random IDs, etc.  See the appendix for more details)?

No.

7) Is the data collection covered by the existing Firefox privacy notice?

Yes.

8) Does there need to be a check-in in the future to determine whether to renew the data?

No, permanent.

Comment 9

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 8987866 [details]
Bug 1470901 - Add telemetry probes for measuring WebRender paint phases.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/253144/diff/1-2/

Comment 10

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 8987867 [details]
Bug 1470901 - Record scene build, scene swap, and render times in telemetry.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/253146/diff/1-2/

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/87d1695413a0
Add telemetry probes for measuring WebRender paint phases. r=chutten
https://hg.mozilla.org/integration/autoland/rev/346b316a0fe4
Record scene build, scene swap, and render times in telemetry. r=sotaro

Comment 12

[Raul Gurzau (:RaulG)]

https://hg.mozilla.org/mozilla-central/rev/87d1695413a0
https://hg.mozilla.org/mozilla-central/rev/346b316a0fe4

Comment 13

[Cristina Coroiu [:ccoroiu]]

https://hg.mozilla.org/mozilla-central/rev/87d1695413a0
https://hg.mozilla.org/mozilla-central/rev/346b316a0fe4