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arXiv · 1210.3368

An optimized conflict-free replicated set

Annette Bieniusa·Marek Zawirski·Nuno Preguiça·Marc Shapiro·Carlos Baquero·Valter Balegas·Sérgio Duarte
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Abstract

Eventual consistency of replicated data supports concurrent updates, reduces latency and improves fault tolerance, but forgoes strong consistency. Accordingly, several cloud computing platforms implement eventually-consistent data types. The set is a widespread and useful abstraction, and many replicated set designs have been proposed. We present a reasoning abstraction, permutation equivalence, that systematizes the characterization of the expected concurrency semantics of concurrent types. Under this framework we present one of the existing conflict-free replicated data types, Observed-Remove Set. Furthermore, in order to decrease the size of meta-data, we propose a new optimization to avoid tombstones. This approach that can be transposed to other data types, such as maps, graphs or sequences.

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Annette Bieniusa, Marek Zawirski, Nuno Preguiça, Marc Shapiro, Carlos Baquero, Valter Balegas, Sérgio Duarte. 2012-10-11. An optimized conflict-free replicated set. https://arxiv.org/abs/1210.3368

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