An Efficient Implementation of Sequentially Consistent Distributed Shared Memories

Recently, distributed shared memory systems have received much attention because such an abstraction simplifies programming. In this paper, we present a data consistency protocol for a distributed system which implements sequentially consistent memories. The protocol is aimed at an environment where no special support for atomic broadcast exists. As compared to previously proposed protocols, our protocol eliminates the need of atomic broadcast and significantly reduces the amount of information flow among the processors. This is realized by maintaining state information and capturing causal relations among read and write operations. Because of this feature, the protocol is well suited to a distributed memory parallel machine, and an experimental implementation is currently in progress on such an architecture.