Simulation analysis of a real-time database buffer manager

Real-time database management systems research has not focused efforts on the specific low level systems support requirements for availability, timeliness and predictability of data access. An important aspect of such database system´s support is the secondary access schemes and in particular database disk buffer allocation schemes. Timing constraints on critical and non-critical transactions in real-time database systems require that resource management strategies and algorithms give preferential treatment to critical transactions. The paper examines buffer management policies in a database system characterized by transactions which have execution deadlines and criticalities. A buffer allocation scheme and two buffer page replacement algorithms are described. A simulation model is used to examine real-time buffer allocation and page replacement algorithms versus a conventional baseline algorithm. The results of the simulation are presented and discussed