Extensions provide capabilities on top of the primary functionality of the collector. Generally, extensions are used for implementing components that can be added to the Collector, but which do not require direct access to telemetry data and are not part of the pipelines (like receivers, processors or exporters). Example extensions are: Health Check extension that responds to health check requests or PProf extension that allows fetching Collector's performance profile.
Supported service extensions (sorted alphabetically):
The contributors repository may have more extensions that can be added to custom builds of the Collector.
The order extensions are specified for the service is important as this is the
order in which each extension will be started and the reverse order in which they
will be shutdown. The ordering is determined in the extensions tag under the
service tag in the configuration file, example:
service:
# Extensions specified below are going to be loaded by the service in the
# order given below, and shutdown on reverse order.
extensions: [health_check, pprof, zpages]Health Check extension enables an HTTP url that can be probed to check the status of the the OpenTelemetry Collector. This extension can be used as a liveness and/or readiness probe on Kubernetes.
The following settings are required:
port(default = 13133): What port to expose HTTP health information.
Example:
extensions:
health_check:The full list of settings exposed for this exporter is documented here with detailed sample configurations here.
Performance Profiler extension enables the golang net/http/pprof endpoint.
This is typically used by developers to collect performance profiles and
investigate issues with the service.
The following settings are required:
endpoint(default = localhost:1777): The endpoint in which the pprof will be listening to. Use localhost: to make it available only locally, or ":" to make it available on all network interfaces.block_profile_fraction(default = 0): Fraction of blocking events that are profiled. A value <= 0 disables profiling. See https://golang.org/pkg/runtime/#SetBlockProfileRate for details.mutex_profile_fraction(default = 0): Fraction of mutex contention events that are profiled. A value <= 0 disables profiling. See https://golang.org/pkg/runtime/#SetMutexProfileFraction for details.
The following settings can be optionally configured:
save_to_file: File name to save the CPU profile to. The profiling starts when the Collector starts and is saved to the file when the Collector is terminated.
Example:
extensions:
pprof:The full list of settings exposed for this exporter are documented here with detailed sample configurations here.
Enables an extension that serves zPages, an HTTP endpoint that provides live data for debugging different components that were properly instrumented for such. All core exporters and receivers provide some zPage instrumentation.
The following settings are required:
endpoint(default = localhost:55679): Specifies the HTTP endpoint that serves zPages. Use localhost: to make it available only locally, or ":" to make it available on all network interfaces.
Example:
extensions:
zpages:The full list of settings exposed for this exporter are documented here with detailed sample configurations here.