Analytical considerations for transactional cache protocols

Since the early nineties transactional cache protocols have been intensively studied in the context of client-server database systems. Research has developed a variety of protocols and compared different aspects of their quality using simulation systems and applying semi-standardized benchmarks. Unfortunately none of the related publications substantiated their experimental findings by thorough analytical considerations. We try to close this gap at least partially by presenting comprensive and highly accurate analytical formulas for quality aspects of two important transactional cache protocols. We consider the non-adaptive variants of the "Callback Read Protocol" (CBR) and the "Optimistic Concurrency Control Protocol" (OCC). The paper studies their cache filling size and the number of messages they produce for the so-called UNIFORM workload. In many cases the cache filling size may considerably differ from a given maximum cache size - a phenomenon which has been overlooked by former publications. Moreover for OCC, we also give a highly accurate formula which forecasts the transaction abortion rate. All formulas are compared against corresponding simulation results in order to validate their correctness