Fixed priority scheduling periodic tasks with varying execution priority
نویسندگان
چکیده
This paper considers the problem of fixed priority scheduling of periodic tasks where each task’s execution priority may vary. Periodic tasks are decomposed into serially executed subtasks. where each subtask is characterized by an execution time and a fixed priority, and is permitted to have a deadline. A method for determining the schedulability of each task is presented along with its theoretical underpinnings. This method can be used to analyze the schedulability of complex task sets which involve interrupts, certain synchronization protocols, nonpreemptible sections and, in general, any mechanism that contributes to a complex priority structure. The method is illustrated with a realistic example.
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