A fully-distributed approach to concurrency control in replicated database systems

Existing algorithms for concurrency control in replicated database systems are semi-distributed because, in these algorithms, only one site completely executes an update and the other sites just commit its writes. The author presents a fully distributed algorithm for concurrency control where each site completely executes every update. This approach has improved resiliency to different kinds of failures, higher parallelism, fast response to user requests, and low communication overhead. The author also presents a performance model of a replicated database system and uses it to study the performance of the proposed algorithm and the algorithm of M. Singhal et al. (1986). The results of the performance study reveal that the proposed approach improves the performance at the cost of nominal I/O overhead