The metric is calculated using the following formula and value ranges from 0 to 1, where 0 indicates the controller thread is constantly processing without breaks, 1 signifies the controller spends most of its time waiting for work:

                      controller idle ratio = idle_time/(active_time+idle_time)

The components are defined as follows:

• active_time: This is the total time the controller thread actively spends processing events or performing computation work rather than waiting for callbacks or external operations
• idle_time: This is the total time the controller thread is not executing any instructions while waiting for either new events to appear in the queue or Raft callback.