Instrumentation

Logging Metrics in Gunicorn

• Gunicorn provides an optional instrumentation of:

  • The arbiter
  • The workers
• This is provided using the statsD protocol over UDP
• Specifically, Gunicorn uses the gunicorn.instrument.statsd module
• As a result, Gunicorn becomes a statsD client

• Using UDP ensures the following:

  • Gunicorn is isolated from the receiving end of statsD
  • Gunicorn is not held up by a slow statsD consumer

Usage of statsD in Gunicorn

• An example of the statsD server is the following:

$ gunicorn --statsd-host=localhost:8125 ...

Details about the statsD Logger

• The statsD logger overrides gunicorn.glogging.Logger
• This tracks all of the requests

• The following metrics are generated:

  • gunicorn.requests: Request rate per seconds
  • gunicorn.request.duration: Histogram of request duration (in milliseconds)
  • gunicorn.workers: Number of workers managed by the arbiter (gauge)
  • gunicorn.log.critical: Rate of critical log messages
  • gunicorn.log.error: Rate of error log messages
  • gunicorn.log.warning: Rate of warning log messages
  • gunicorn.log.exception: Rate of exceptional log messages

References

• Gunicorn Documentation