2571	 An Analytic Model of the Hasp Execution Task Monitor	 The HASP Execution Task Monitor periodically rearranges the OS dispatching chain to give tasks preemptive execution priority in inverse order to that of their cpu utilization history. The effect is to keep the I O bound tasks active and to prevent cpu bound tasks from locking out other tasks. This paper develops a simple model of the Execution Task Monitor and employs it to study the effectiveness of the monitor in improving system performance. A modified strategy monitor control is investigated for the case of task execution in a memory hierarchy of varying speeds. Hasp OS dispatching scheduling modeling performance evaluation
