Augustus: scalable and robust storage for cloud applications

Cloud-scale storage applications have strict requirements. On the one hand, they require scalable throughput; on the other hand, many applications would largely benefit from strong consistency. Since these requirements are sometimes considered contradictory, the subject has split the community with one side defending scalability at any cost (the "NoSQL" side), and the other side holding on time-proven transactional storage systems (the "SQL" side). In this paper, we present Augustus, a system that aims to bridge the sides by offering low-cost transactions with strong consistency and scalable throughput. Furthermore, Augustus assumes Byzantine failures to ensure data consistency even in the most hostile environments. We evaluated Augustus with a suite of micro-benchmarks, Buzzer (a Twitter-like service), and BFT Derby (an SQL engine based on Apache Derby).