Increasing Concurrency of Transactions Using Delayed Certification in Mobile DBMSs

Abstract

As the server in mobile environments may not have any information about the state of its clients’ cache(stateless server), using broadcasting approach to transmit the list of updated data to numerous concurrent mobile clients is an attractive approach. In this paper, a new concurrency control protocol is proposed to reduce aborts of concurrent transactions. The proposed protocol can improve the throughput of transactions by increasing the number of transactions which can be committed by the server during the same broadcasting interval. For this, with the proposed protocol, the server delays the certification of transactions until the next broadcasting point. The protocol adopts adaptive broadcasting as the way of sending invalidation reports, which shows stable performance by choosing appropriate broadcasting strategy between synchronous and asynchronous broadcastings.