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arXiv · 1510.06967

Opacity Proof for CaPR+ Algorithm

Anshu S Anand·R K Shyamasundar·Sathya Peri
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Abstract

In this paper, we describe an enhanced Automatic Check- pointing and Partial Rollback algorithm(CaP R + ) to realize Software Transactional Memory(STM) that is based on con- tinuous conflict detection, lazy versioning with automatic checkpointing, and partial rollback. Further, we provide a proof of correctness of CaP R+ algorithm, in particular, Opacity, a STM correctness criterion, that precisely captures the intuitive correctness guarantees required of transactional memories. The algorithm provides a natural way to realize a hybrid system of pure aborts and partial rollbacks. We have also implemented the algorithm, and shown its effectiveness with reference to the Red-black tree micro-benchmark and STAMP benchmarks. The results obtained demonstrate the effectiveness of the Partial Rollback mechanism over pure abort mechanisms, particularly in applications consisting of large transaction lengths.

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Anshu S Anand, R K Shyamasundar, Sathya Peri. 2015-10-23. Opacity Proof for CaPR+ Algorithm. https://arxiv.org/abs/1510.06967

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