The power state (host power on or off) recommendations generated by the vSphere DPM feature are assigned priorities that range from priority-one recommendations to priority-five recommendations.
These priority ratings are based on the amount of over- or under-utilization found in the DRS cluster and the improvement that is expected from the intended host power state change. A priority-one recommendation is mandatory, while a priority-five recommendation brings only slight improvement.
The threshold is configured under Power Management in the cluster’s Settings dialog box. Each level you move the vSphere DPM Threshold slider to the right allows the inclusion of one more lower level of priority in the set of recommendations that are executed automatically or appear as recommendations to be manually executed. At the Conservative setting, vSphere DPM only generates priority-one recommendations, the next level to the right only priority-two and higher, and so on, down to the Aggressive level which generates priority-five recommendations and higher (that is, all recommendations.)
The DRS threshold and the vSphere DPM threshold are essentially independent. You can differentiate the aggressiveness of the migration and host-power-state recommendations they respectively provide.