Evaluating the effectiveness of fault tolerance in replicated database management systems

Database management systems (DBMS) achieve high availability and fault tolerance usually by replication. However fault tolerance does not come for free. Therefore, DBMSs serving critical applications with real time requirements must find a trade of between fault tolerance cost and performance. The purpose of this study is two-fold. It evaluates the effectiveness of DBMS fault tolerance in the presence of corruption in database buffer cache, which poses serious threat to the integrity requirement of the DBMSs. The first experiment of this study evaluates the effectiveness of fault tolerance, and the fault impact on database integrity, performance, and availability on a replicated DBMS, ClustRa, in the presence of software faults that corrupt the volatile data buffer cache. The second experiment identifies the weak data structure components in the data buffer cache that give fatal consequences when corrupted, and suggest the need for some forms of guarding them individually or collectively.