Date Added: Dec 2009
Feedback control techniques have recently been applied to a variety of real-time systems. However, a fundamental issue that was left out is guaranteeing system controllability and the feasibility of applying feedback control to such systems. No control algorithms can effectively control a system which itself is uncontrollable or infeasible. In this paper, the authors use the multi-processor utilization control problem as a representative example to study the controllability and feasibility of distributed real-time systems. They prove that controllability and feasibility of a system depend crucially on end-to-end task allocations.