Closed Bug 1529352 Opened 6 years ago Closed 5 years ago

Collect WebRender performance metrics in release


(Core :: Graphics: WebRender, enhancement)

66 Branch
Not set



Tracking Status
firefox66 --- fixed
firefox67 --- fixed


(Reporter: tdsmith, Assigned: tdsmith)




(2 files)

Some of the probes we're hoping to use to monitor WebRender performance in release are not currently collected in release.

These probes are:

  • canvas_webgl_success
  • composite_time
  • device_reset_reason

FX_TAB_SWITCH_COMPOSITE_E10S_MS is also set to stop recording in 70; we may as well extend that to 73 while we're here in order to be compatible with the Jan 2020 horizon that the Webrender study currently has.

A handful of probes that are useful for measuring the performance of WebRender are not currently collected in the release channel.

Since we're planning to begin deploying WebRender in release on an experimental basis in 66, we should make sure that these probes are available there, so that we can assess its performance.

Attached file Data collection review
Attachment #9045500 - Flags: review?(chutten)
Comment on attachment 9045500 [details]
Data collection review


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

Yes. This collection is Telemetry so is documented in its definitions file ([Histograms.json](, the [Probe Dictionary](, and on's [Measurement Dashboards](

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

Yes. This collection is Telemetry so can be controlled through Firefox's Preferences.

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

Some of the collection is permanent and will continue to be monitored by rhunt.

    Using the category system of data types on the Mozilla wiki, what collection type of data do the requested measurements fall under?

Category 1, Technical.

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

Default on for all channels.

    Does the instrumentation include the addition of any new identifiers?


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


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

Only for FX_TAB_SWITCH_COMPOSITE_E10S_MS which should be renewed or removed before it expires in Firefox 73.

Result: datareview+
Attachment #9045500 - Flags: review?(chutten) → data-review+
Pushed by
Collect WebRender probes in release r=jrmuizel

Comment on attachment 9045493 [details]
Bug 1529352 - Collect WebRender probes in release r?jrmuizel

Beta/Release Uplift Approval Request

  • Feature/Bug causing the regression: n/a
  • User impact if declined: If declined we won't be able to use these measurements to assess WebRender in the experiment we're planning for the 66 release cycle, which could result in us missing a perf impact or delaying the WR deployment.
  • Is this code covered by automated tests?: Unknown
  • Has the fix been verified in Nightly?: Yes
  • Needs manual test from QE?: No
  • If yes, steps to reproduce:
  • List of other uplifts needed: None
  • Risk to taking this patch: Low
  • Why is the change risky/not risky? (and alternatives if risky): Only changes histogram definitions
  • String changes made/needed: none
Attachment #9045493 - Flags: approval-mozilla-beta?

Comment on attachment 9045493 [details]
Bug 1529352 - Collect WebRender probes in release r?jrmuizel

Turn on some already existing telemetry on release.
Has data review. OK for beta 12 uplift.

Attachment #9045493 - Flags: approval-mozilla-beta? → approval-mozilla-beta+
Closed: 5 years ago
Resolution: --- → FIXED
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