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arXiv · 1805.04840

An Almost Tight RMR Lower Bound for Abortable Test-And-Set

Aryaz Eghbali·Philipp Woelfel
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Abstract

We prove a lower bound of Omega(log n/loglog n) for the remote memory reference (RMR) complexity of abortable test-and-set (leader election) in the cache-coherent (CC) and the distributed shared memory (DSM) model. This separates the complexities of abortable and non-abortable test-and-set, as the latter has constant RMR complexity (Golab, Hendler, Woelfel, SIAM Journal of Computing Vol. 39, 2010). Golab, Hendler, Hadzilacos and Woelfel (Distributed Computing Vol. 25, 2012) showed that compare-and-swap can be implemented from registers and TAS objects with constant RMR complexity. We observe that a small modification to that implementation is abortable, provided that the used TAS objects are abortable.

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Aryaz Eghbali, Philipp Woelfel. 2018-05-13. An Almost Tight RMR Lower Bound for Abortable Test-And-Set. https://arxiv.org/abs/1805.04840

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