Based Network Of Workstations, Distributed Shared Memory System Design

Distributed shared memory(DSM) systems implement the shared memory abstraction on physically distributed memory systems. The DSM system hides the underlying message passing mechanism from application programmers and allows a shared memory programming paradigm. DSM systems keep the programmability and portability of shared memory systems, and yet inherit the scalability and cost-effectiveness of underlying distributed memory systems. Consequently, DSM systems offer a viable solution for building large-scale, high-performance computer systems, and DSM has become a very active research area.This thesis describes the key issues of distributed shared memory systems. One of the most important issues of DSM is the memory consistency model. As the contract between the software and the memory, memory consistency model specifies the behavior of memory with respect to read and write operations in a shared memory system. We review several proposed models and analyze their constraints on access event ordering. We indicate the sequential consistency model's constraints on the program order and access atomicity, and the relaxation of other models on these constraints. We also demonstrate the benefits of the relaxed model, such as lazy release consistency model, in DSM systems.In this thesis, we introduce the implementation approaches of DSM systems, and give an integrated overview of the design choices of building a software DSM system, we also indicate that the primary challenge in building a software DSM system is to reduce the amount of communication that is required to maintain consistency.The improved microprocessor performance and network technology are...