Towards a unified model for performance evaluation of concurrency control

Research in the area of concurrency-control performance evaluation has been extensive in the past few years. Unfortunately, conclusions arrived at by many of the researchers were incomparable and at times contradictory, because of the different assumptions and performance models used. Therefore, a unified and complete performance model is needed. We propose a framework for concurrency-control performance evaluation in single-site databases. Areas of performance studies are classified, and a performance model is suggested. Finally, we give a complete example of a performance study for the dynamic two-phase locking algorithm using this framework. Two effects were studied: those of granularity and the read-write mix.