In this paper, we shall use the same analytical model to investigate the behaviour of the paging drum when the degree of multiprogramming is set to its optimal value. The main conclusion, which corroborates the general feeling on performance of virtual memory systems [3, 4, 5], is that drum utilization remains in the 50% range whenever CPU utilization is maximized, if no resource is saturated. The results are validated through simulation experiments in order to relax some theoretical assumptions used in the analytical model and to take into account some detailed mechanisms such as CPU overheads. As an application, an adaptive control algorithm based on the activity of the paging device is proposed. The algorithm has been simulated and comparisons with results reported in [2] are presented.Moreover, after investigations we show also that optimal performance can only be achieved through a balanced use of the different resources of the system. This conclusion cross-checks and extends Buzen's theoretical results [6] and Wulf's practical ones [7].