The Metrics Facility provides the following functionality:
Collection of gmond provided metrics using the Orchestration Agent.
Retrieval of instantaneous metric values via resource.metrics.<METRIC_NAME> fact space, where <METRIC_NAME> is the name of the metric.
Deployable Round Robin Database (RRD) (data aggregation) definition using XML .metric files, which allows flexible definition of aggregation periods. For example, using resource.metrics.<METRIC_NAME>.10_minute.average as a 10-minute aggregation period separate from resource.metrics.<METRIC_NAME>.1_hour.average.
Retrieval of an array of aggregated metric values using resource.metrics.<METRIC_NAME>.xxx.values.
Zero-configuration for core Ganglia metrics. The Orchestration Agent automatically discovers if gmond is running on a resource, and the Orchestration Server collects and, if a .metric file is configured, aggregates those metrics.
Persistence of collected RRD data across server restart and high availability fail-over conditions.