Benefits of Weak Coherence for Distributed shared Memory Systems

This paper describes a new scheme for weakly coherent, distributed shared memory systems. It shows that for most applications the semantics of weak coherence are sufficient. After sketching the bmic implementation schemes for weak coherence protocols it presents their benefits, mainly an improved exploitation of parallelism. Not only latency masking for write operations is exploited but also techniques like accumulating u,pdate and invalidation messages are introduced. First results ofa prototype implementation are given.