Adaptability experiments in the RAID distributed database system

A series of experiments is being conducted on the RAID distributed database system to study the performance and reliability implications of providing static and dynamic adaptability. The authors´ studies of the cost of their adaptable implementation were conducted in the context of the concurrency controller and the replication controller. It is shown that adaptable implementations can be provided at costs comparable to those of special-purpose implementations. The experimentation with dynamic adaptability focuses on concurrency control. It is shown that dynamic adaptability can result in performance benefits and that system reconfiguration can be accomplished dynamically with less cost than stopping the system, performing reconfiguration, and then restarting the system. The authors´ examination of the costs of providing greater data availability includes studying the replication control and atomicity control subsystems of RAID. The cost associated with increasing availability in an adaptable scheme of replication control and commit protocols is demonstrated