Minimizing Consistency Traffic in a Versioned Object Transactional DSM

In this paper we describe an extension of the LOTEC (Lazy Object Transactional Entry Consistency) protocol designed to minimize the network traffic required to maintain consistency in a software-only DSM (Distributed Shared Memory). Unlike traditional DSM systems which are targetted for shared memory parallel computing, the protocols discussed in this paper are designed to support distributed persistent object systems. The object environment affords improved semantic analyses that can be exploited to improve the efficiency of consistency maintenance. This paper contributes by defining a mechanism for reducing consistency traffic by partitioning each object into a number of “chunks” based on method-attribute affinity so that the amount of data transferred in update messages is minimized. Some initial simulation results for the extended protocol are also presented that illustrate the effectiveness of our chunking technique.