Using importance of transactions and optimistic concurrency control in firm real-time databases

In a real-time database system, it is difficult to meet all timing constraints due to the consistency requirements of the underlying database. However, when the transactions in the system are heterogeneous, they are not of the same importance some are of greater importance than others. In this paper, we propose a new optimistic concurrency control protocol called OCC-PDATI which uses information about the importance of the transactions in the conflict resolution. Performance studies of our protocol have been carried out in the prototype real-time database system. The results clearly indicate that OCC-PDATI meets the goal of favoring transactions of high importance.