Using trend analysis and forecasting, the Capacity Service helps you understand how a cluster is performing within its current environment and workload, and gain a better sense of how time affects those trends, both past and future. Several types of metrics are collected by the Capacity Service, including Cassandra-specific and platform-specific metrics (for example, disk and network metrics), at both the node and table level (where applicable). These metrics are stored in Cassandra on the cluster being managed by default. That metrics data can be stored on a separate dedicated cluster as well.
The Trend Analysis component of the Capacity Service allows viewing historical metrics for any node or table, as well as aggregates across an entire cluster.
The Forecast feature allows viewing a predicted trend for any metric, based on collected historical data. A predicted trend uses polynomial curve fitting against historical data. By default, the polynomial equation is degree 3. If the predicted results need adjustment or improvement, send the results to DSE OpsCenter using the Help us improve these results from the Forecasting dialog, and contact DataStax Support for assistance.