Schedulability Analysis of Global Memory-predictable Scheduling

The use of multicore CPUs in real-time systems poses significant challenges in estimating their temporal behavior. A factor that has a large impact on this issue is the contention for access to main memory among multiple cores. To overcome this problem, an execution model called PREM has been previously introduced to co-schedule CPU execution and accesses to main memory without relying on hardware arbiters. In this paper, we provide a global schedulability analysis for this predictable execution model, and we prove its correctness. We also evaluate the effectiveness of the proposed solution with extensive simulations. The results show a significant advantage of the proposed solution when compared to contention execution in which tasks access main memory unpredictably.