An Empirical Analysis of the Object-Oriented Database Concurrency Control Mechanism O2C2

In this paper, we present an empirical analysis of the object-oriented database concurrency control mechanism named OC as specified in Olsen (1995). OC is a lock-based mechanism that is designed specifically to take advantage of the object-oriented database model as specified in Kim (1990). The OC strategy is two-phased and uses eight different kinds of locks. The eight types of locks are Intention Read (IR), Intention Write (IW), Read (R), Write (W), Method Read (MR), Method Write (MW), Class Definition Read (CDR), and Class Definition Write (CDW). This study makes three distinct contributions. First, a model is presented for simulating concurrency control mechanisms in an object-oriented database environment. Much like the work done in Agrawal, Carey and Livny (1987) in which a simulation model appropriate for relational database concurrency control was presented, a model for simulating object-oriented database concurrency control is established. Reasonable assumptions and parameters concerning the database model, hardware, and contention levels are developed and presented. The second contribution is a theoretical development of an object-oriented database transaction processing environment as it relates to the concurrency control function. This is similar to the environment presented in Agrawal, Carey and Livny (1987) but is modified for the object-oriented An Empirical Analysis of the Object-Oriented Database Concurrency Control Mechanism OC