Telemetry pings

A Telemetry ping is the data that we send to Mozillas Telemetry servers.

That data is stored as a JSON object client-side and contains common information to all pings and a payload specific to a certain ping types.

The top-level structure is defined by the common ping format format. It contains:

  • some basic information shared between different ping types
  • the environment data (optional)
  • the data specific to the ping type, the payload.

Ping types

We send Telemetry with different ping types. The main ping is the ping that contains the bulk of the Telemetry measurements for Firefox. For more specific use-cases, we send other ping types.

Pings sent from code that ships with Firefox are listed in the data documentation.

Important examples are:

  • main - contains the information collected by Telemetry (Histograms, hang stacks, ...)
  • saved-session - has the same format as a main ping, but it contains the “classic” Telemetry payload with measurements covering the whole browser session. This is only a separate type to make storage of saved-session easier server-side. This is temporary and will be removed soon.
  • crash - a ping that is captured and sent after Firefox crashed.
  • activation - planned - sent right after installation or profile creation
  • upgrade - planned - sent right after an upgrade
  • deletion - sent when FHR upload is disabled, requesting deletion of the data associated with this user