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Instant Recovery for Main Memory Databases

With the emergence of new hardware technologies, new opportunities arise and existing database architectures have to be rethought to fully exploit them. In particular, recovery mechanisms of current main-memory database systems are tuned to efficiently work on block-oriented, high-latency storage devices. These devices create a bottleneck during transaction processing. In this paper, we investigate the opportunities given by the upcoming Storage Class Memory (SCM) technology for database system recovery mechanisms. In contrast to traditional block-oriented devices, SCM is byte-addressable and offers a latency close to that of DRAM. We propose a novel main-memory database architecture that directly operates in SCM, eliminates the need for logging mechanisms, and provides a way to trade recovery time with the overall query performance. We implemented these concepts in our prototype SOFORT. Our evaluation shows that we are able to achieve instant recovery of the DBMS while removing the need for transaction rollbacks after failure.