Allocating and scheduling tasks in multiple fieldbus real-time systems

We consider real-time systems connected via several fieldbuses. Validating such systems consists of proving that tasks meet their end-to-end deadlines. Tasks are scheduled on processors by fixed-priority schedulers. We propose an automatic method for allocating tasks on processors and assigning priorities to tasks so that every deadline is met. Allocation and scheduling are simultaneously achieved. We do not limit the search space to a specific priority rule (such as rate monotonic or deadline monotonic). Feasible schedules are validated by a holistic analysis. Numerical results of the method are lastly presented on a real-size application. Our tool will be a beneficial help to design real-time distributed systems.

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