Scalable cache coherence for shared memory multiprocessors

Abstract

This paper presents a performance analysis of a new directory based cache coherence protocol. We compare the fully mapped centralized directory protocol with a distributed directory protocol developed by us. The distributed directory protocol is based on a linked list of caches and is more scalable in terms of cost and performance. It does not require the network to preserve the order of messages and allows adaptive routing so that network performance may be more robust. Simulation results show that the distributed directory protocol has better performance than the centralized directory protocol for the benchmarks we have analyzed.