An Exact Schedulability Analysis for Global Fixed-Priority Scheduling of the AER Task Model

Commercial off-the-shelf (COTS) multi-core platforms offer high performance and large availability of processing resources. Increased contention when accessing shared resources is a result of the high parallelism and one of the main challenges when realtime applications are deployed to these platforms. As a result, several execution models have been proposed to avoid contention by separating access to shared resources from execution. In this work, we consider the Acquisition-Execution-Restitution (AER) model where contention to shared resources is avoided by design. We propose an exact schedulability test for the AER model under global fixed-priority scheduling using timed automata where we describe the schedulability problem as a reachability problem. To the best of our knowledge, this is the first exact schedulability test for the AER model under global fixed-priority scheduling on multiprocessor platforms. The performance of the proposed approach is evaluated using synthetic experiments and provides up to 65% more schedulable task sets than the state-of-the-art.