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arXiv · 1905.06760

Persistent Buffer Management with Optimistic Consistency

Lucas Lersch·Wolfgang Lehner·Ismail Oukid
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Abstract

Finding the best way to leverage non-volatile memory (NVM) on modern database systems is still an open problem. The answer is far from trivial since the clear boundary between memory and storage present in most systems seems to be incompatible with the intrinsic memory-storage duality of NVM. Rather than treating NVM either solely as memory or solely as storage, in this work we propose how NVM can be simultaneously used as both in the context of modern database systems. We design a persistent buffer pool on NVM, enabling pages to be directly read/written by the CPU (like memory) while recovering corrupted pages after a failure (like storage). The main benefits of our approach are an easy integration in the existing database architectures, reduced costs (by replacing DRAM with NVM), and faster peak-performance recovery.

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Lucas Lersch, Wolfgang Lehner, Ismail Oukid. 2019-05-16. Persistent Buffer Management with Optimistic Consistency. https://doi.org/10.1145/3329785.3329931

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