Distributed real-time optimistic concurrency control protocol

Although many recent studies have suggested that optimistic concurrency control (OCC) with dynamic adjustment of serialization order (DASO) is more suitable than two phase locking (2PL) for real-time database systems (RTDBS), most of the protocols proposed for DRTDBS are based on 2PL. When OCC with DASO is extended to DRTDBS, a number of issues have to be resolved. These include the heavy overhead for maintaining the dynamic serialization order of transactions in a distributed environment and the resolution of deadlock due to distributed validation. A new distributed real-time OCC algorithm with DASO, called DOCC-DA, is proposed with the above issues taking into consideration. Its performance has been compared with the distributed OCC protocol without dynamic serialization order adjustment. The results indicate that the performance of the proposed protocol is better.