Build Telemetry

The build system (specifically, all the build tooling hooked up to ./mach) has been configured to collect metrics data points and errors for various build system actions. This data helps drive team planning for the build team and ensure that resources are applied to build processes that need them most. You can opt-in to send telemetry to Mozilla during ./mach bootstrap or by editing your .mozbuild/machrc file.

Glean Telemetry

Mozbuild reports data using Glean via Mach Telemetry. The metrics collected are documented here.

Error Reporting

./mach uses Sentry to automatically report errors to our issue-tracking dashboard.

Information captured

Sentry automatically collects useful information surrounding the error to help the build team discover what caused the issue and how to reproduce it. This information includes:

  • Environmental information, such as the computer name, timestamp, Python runtime and Python module versions

  • Process arguments

  • The stack trace of the error, including contextual information:

    • The data contained in the exception

    • Functions and their respective source file names, line numbers

    • Variables in each frame

  • Sentry “Breadcrumbs”, which are important events that have happened which help contextualize the error, such as:

    • An HTTP request has occurred

    • A subprocess has been spawned

    • Logging has occurred

Note that file paths may be captured, which include absolute paths (potentially including usernames).