A View-based Consistency Model based on Transparent Data Selection in Distributed Shared Memory

Abstract

This paper proposes a novel View-based Consistency model for Distributed Shared Memory, in which a new concept, view, is coined. A view is a set of data objects that a processor has the right to access in the shared memory. The View-based Consistency model only requires that the data objects of a processor's view are updated before a processor accesses them. In this way, it can achieve the maximum relaxation of constraints on modification propagation and execution in data-race-free programs. This paper first briefly reviews a number of related consistency models in terms of their use of three techniques -- time, processor and data selection -- which each eliminate some unnecessary propagation of memory modifications while guaranteeing sequential consistency for data-race-free programs. Then, we present the View-based Consistency model and its implementation. In contrast with other models, the View-based Consistency model can achieve transparent data selection without programmer annotation and can offer the maximum performance advantage. Differences among related work are discussed through illustrative examples