What is observability? What are telemetry data?

About

Observability permits the observation of the state of an application via telemetry data.

There are 3 telemetry data type (known also as dimensions or pillars)

• metrics (in-memory metrics)
• log (event file logging)
• trace (stack trace registration)

Metrics

Metrics are:

• in-memory time series data
• that permits building a dashboard of your engine, to check the activity of your application
• and alerts in case of issues

Logs

Log are events stored in files. They are managed by an event logger.

There are 2 kinds:

• textual event with a state as INFO or ERROR
• event registration with data (Event Analytics)

They can be:

• processed to derive metrics
• read to see the activity or state of an application and debug any problem.

Trace

Traces logs the stack trace.

They are managed by a tracing system.

More

• Adrian Cole’s talk on Observability 3 Ways