Data Replication in a Distributed System : APerformance

In this paper we investigate the performance issues of data replication in a loosely coupled distributed database system, where a set of database servers are connected via a network. A database repli-cation scheme, Replication with Divergence, which allows some degree of divergence between the primary and the secondary copies of the same data object, is compared to other two schemes that, respectively, disallows replication and maintains all replicated copies consistent at all times. The impact of some tunable factors, such as cache size and the update propagation probability, on the performance of Replication with Divergence is also investigated. These results shed light on the performance issues that were not addressed in previous studies on replication of distributed database systems.