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arXiv · 1512.08943

Reconfigurable State Machine Replication from Non-Reconfigurable Building Blocks

Vita Bortnikov·Gregory Chockler·Dmitri Perelman·Alexey Roytman·Shlomit Shachor·Ilya Shnayderman
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Abstract

Reconfigurable state machine replication is an important enabler of elasticity for replicated cloud services, which must be able to dynamically adjust their size as a function of changing load and resource availability. We introduce a new generic framework to allow the reconfigurable state machine implementation to be derived from a collection of arbitrary non-reconfigurable state machines. Our reduction framework follows the black box approach, and does not make any assumptions with respect to its execution environment apart from reliable channels. It allows higher-level services to leverage speculative command execution to ensure uninterrupted progress during the reconfiguration periods as well as in situations where failures prevent the reconfiguration agreement from being reached in a timely fashion. We apply our framework to obtain a reconfigurable speculative state machine from the non-reconfigurable Paxos implementation, and analyze its performance on a realistic distributed testbed. Our results show that our framework incurs negligible overheads in the absence of reconfiguration, and allows steady throughput to be maintained throughout the reconfiguration periods.

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Vita Bortnikov, Gregory Chockler, Dmitri Perelman, Alexey Roytman, Shlomit Shachor, Ilya Shnayderman. 2015-12-30. Reconfigurable State Machine Replication from Non-Reconfigurable Building Blocks. https://arxiv.org/abs/1512.08943

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