A Heterogeneous Preemptive and Non-preemptive Scheduling Approach for Real-Time Systems on Multiprocessors

The correct functioning of real-time systems depends not only on the logically correct response, but also on its timing. This type of system is increasingly present today and the processing demand is such that complex multicore processors are needed. The development of multiprocessors is ahead of the analysis techniques of such systems and it is therefore necessary to promote reliability and to reduce over-specified systems. Depending on the processor architecture, the values obtained by computing WCET (Worst Case Execution Time) are incompatible with the scheduling model that creates a fundamental contradiction between the assumptions of WCET calculation and scheduling algorithms. This work proposes the use of a heterogeneous approach where part of the multiprocessor cores operate under preemptive and part under a non-preemptive scheduling. The analysis shows that there are advantages in using the heterogeneous approach.