Multiprocessor design options and the Silicon Graphics S2MP architecture Original Research Article

Most multiprocessors can be classified as one of four types: message-passing or MPP systems, clusters, shared-memory multiprocessors, and parallel vector processors. This paper discusses a new model, the scalable shared memory multiprocessor (SSMP), which removes the drawbacks of the traditional SMP systems. The first part of this paper reviews current multiprocessor alternatives, and introduces the scalable SMP architecture. The second part of the paper focuses on a particular instance of a scalable SMP, the Silicon Graphics Origin multiprocessor and its S2MP memory architecture. We give an overview of the Origin system and then discuss some of the important design trade-offs in the architecture and implementation of the system. In the final section we examine technology trends and predict that clusters of scalable shared-memory multiprocessors will become the dominate multiprocessor architecture.