Controller
Before installation, it is good to estimate your deployment size based on the number of nodes. For Java, for example, a node corresponds to a JVM. However, the best indicator of the actual workload on your Controller is provided by the metric ingestion rate.
After initial installation, verify your Controller sizing using the metric upload rate. You then need to continue to monitor the Controller for changing workload brought about by changes in the monitored application, its usage patterns, or in the Splunk AppDynamics configuration.