Performance optimization of real time control systems using variable time period

This paper presents a strategy for optimization of scheduling for a set of real time control tasks using variable time periods. We assume non-preemptive scheduling of the tasks. The time period for each task is selected in such a way so that the performance of the system is optimized. An offline assignment of periods using branch and bound based methodology is proposed to find an optimal schedule for the tasks. An interval scheduling scheme is presented to overcome the computational overhead of variable time period approach. We propose a greedy approach to solve this problem quickly. We present a comparative analysis of our approaches with traditional non-preemptive EDF scheduling. We observed that 30%-50% gain in overall performance for optimal solution and 10%-30% gain using greedy approach. The computation time for greedy approach is significantly small compared to branch and bound based method.