CHOOSING TASK PERIODS TO MINIMIZE SYSTEM UTILIZATION IN TIME TRIGGERED SYSTEMS

The analysis associated with priority based scheduling usually assumes that task periods are fixed by operational requirements. In this pape r we consider systems in which the overriding requirement is to recogn ise and respond to events originating in the system's environment. An algorithm is presented which can deterministically choose task periods so that event deadlines are satisfied, whilst attempting to maximise the number of such events which can be dealt with. Although it is show n that a simple optimal priority ordering scheme is not possible, an e ffective heuristic for choosing priorities is presented.