Metrics are system attributes which influence scaling decisions - e.g., CPU usage, RAM usage, etc. In context of Red5 and Red5 Pro, important metrics would be: CPU usage, JVM memory, connections and streams.

Metrics are used to set Alarms internally by defining Thresholds. When a Metric value violates the defined threshold value it is termed as a "Threshold violation".

The current of Autoscaler concerns itself with only CONNECTION LOAD PERCENTAGE and hence the only Metric it deals with is CONNECTIONS.