A multi-granularity locking-based concurrency control in object-oriented database systems

Abstract In this paper, a concurrency control scheme to increase concurrency among methods in object-oriented database systems (OODBs) is presented. The author is concerned with all types of access to an object: instance access and class definition access. For instance access, the proposed work has the following characteristics. First, construction of commutativity relation among methods can be automated. Second, it provides more concurrency by taking attributes as locking granularity. Third, deadlocks due to lock escalation can be reduced. Finally, concurrency is increased further with the use of run-time information. For class definition access, the proposed work allows class definition access methods to run concurrently by taking fine granularity. The proposed work also allows more parallelism between class definition access methods and instance access methods. For the performance evaluation of the proposed scheme, a simulation model is constructed. Using this model, the proposed technique is then compared with the two existing techniques. The performance studies show that the proposed scheme is superior to existing works.