Promotion and demotion of extents for each storage pool is determined based on a storage pool state defined by demanded activity and demanded capacity. Promotion and demotion of extents for each storage group is determined based on whether the storage group is performing at SLO, above SLO or below SLO. Events are identified and stored in local records using hash tables. The locally stored events are used to update a database of historical extent activity. A moving average of extent activity is used to calculate the demanded activity.