Exploiting method semantics in client cache consistency protocols for object-oriented databases

Data-shipping systems are commonly used in client-server object-oriented databases (OODB). This is intended to utilise clients' resources and improve scalability by allowing clients to run transactions locally after fetching the required database items from the database server. A consequence of this is that a database item can be cached at more than one client. This therefore raises issues regarding client cache consistency and concurrency control. A number of client cache consistency protocols have been studied, and some approaches to concurrency control for OODB have been proposed. Existing client consistency protocols, however, do not consider method semantics in concurrency control. This study proposes a client cache consistency protocol where method semantics can be exploited in concurrency control. It identifies issues regarding the use of method semantics for the protocol and investigates the performance using simulation. The performance results show that this can result in performance gains when compared to existing protocols.