A struct used by the GenMetrics reporting process to periodically publish metrics data for a GenServer cluster.

The fields are:

• cluster - the associated GenMetrics.GenServer.Cluster

• start - the start time for the current metrics window interval

• duration - the length (ms) of the current metrics window interval

• summary - a list of GenMetrics.GenServer.Summary, item per process on the pipeline

• stats - (optional) a list of GenMetrics.GenServer.Server