Strongly consistent replication for a bargain

Strong consistency is an important correctness property for replicated databases. It ensures that each transaction accesses the latest committed database state as provided in centralized databases. Achieving strong consistency in replicated databases is a major performance challenge and is typically not provided, exposing inconsistent data to client applications. We propose two scalable techniques that exploit lazy update propagation and workload information to guarantee strong consistency by delaying transaction start. We implement a prototype replicated database system and incorporate the proposed techniques for providing strong consistency. Extensive experiments using both a micro-benchmark and the TPC-W benchmark demonstrate that our proposals are viable and achieve considerable scalability while maintaining strong consistency.