In this paper, we describe a consistency control algorithm for managing replicated files in the face of network partitioning due to node or communication link failures. It adopts a pessimistic approach in that mutual ...
详细信息
In this paper, we describe a consistency control algorithm for managing replicated files in the face of network partitioning due to node or communication link failures. It adopts a pessimistic approach in that mutual consistency among copies of a file is maintained by permitting files to be accessed only in a single partition at any given time. Our algorithm simplifies the Davcev-Burkhard 'dynamic voting' algorithm and also improves its availability by adding the notion of 'linearly ordered copies.' We also give a proof that any pessimistic algorithm with fresh reads is one-copy serializable. [ABSTRACT FROM AUTHOR]
We consider the effect on system performance of the distribution of a data base in the form of multiple copies at distinct sites. The purpose of our analysis is to determine the gain in READ throughput that can be obt...
详细信息
We consider the effect on system performance of the distribution of a data base in the form of multiple copies at distinct sites. The purpose of our analysis is to determine the gain in READ throughput that can be obtained in the presence of consistency preserving algorithms that have to be implemented when UPDATE operations are carried out on each copy. We show that READ throughput diminishes if the number of copies exceeds an optimal value. The theoretical model we develop is applied to a system in which consistency is preserved through the use of Ellis' ring algorithm.
暂无评论