Speci cation-Based Parameter-Model Interaction: Towards a Correct Re ection of Memory Characteristics in a DSM Cluster Simulation

A DSM (Distributed-Shared Memory) cluster is an attractive parallel computing platform for scienti c research as it provides programming advantages within a scalable and cost-e ective hardware solution. This bene t derives from the fact that a DSM system provides a shared-memory abstraction on top of a distributed-memory machine by caching data replicas locally. In this respect, a coherence protocol is a vital component responsible for assuring data consistency across all replicas. The design of coherence protocols impacts a DSM system in terms of both performance and accuracy. Performance is often measured via simulation and various veri cation techniques have been proposed to deal with protocol accuracy. Nevertheless, integrating accuracy veri cation into a DSM cluster simulation to ensure correct simulation results is still an open issue. In this paper, we address three properties of a coherence protocol (safety, liveness, and inclusion) without which errors may occur in the simulation results. We propose a Speci cation-based ParameterModel Interaction (SPMI) technique to detect these cases in a particular DSM cluster simulation called DSiMCluster. Our experimental results demonstrate that with SPMI, DSiMCluster can ensure the coherence protocol properties and provides a correct re ection in the simulation model of the memory characteristics of real shared-memory and distributed-shared memory multiprocessors.