1. A method comprising: for each memory power management mode of a plurality of memory power management modes supported by one or more memory modules in a memory system of a computer system, wherein each of the plurality of memory power management modes comprises at least a high power state and a low power state: programming the memory system to use the memory power management mode, monitoring a power state of the memory system in the programmed memory power management mode during execution of an application, generating data during the monitoring that describes the monitored power state, storing the data generated during the monitoring in the one or more registers, and reading the data from the one or more registers in response to completing the execution of the application; and processing the data corresponding to each of the plurality of memory power management modes to identify a selected memory power management mode to be used during subsequent executions of the application.