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arXiv · 1510.00116

A Wait-Free Stack

Seep Goel·Pooja Aggarwal·Smruti R. Sarangi
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Abstract

In this paper, we describe a novel algorithm to create a con- current wait-free stack. To the best of our knowledge, this is the first wait-free algorithm for a general purpose stack. In the past, researchers have proposed restricted wait-free implementations of stacks, lock-free implementations, and efficient universal constructions that can support wait-free stacks. The crux of our wait-free implementation is a fast pop operation that does not modify the stack top; instead, it walks down the stack till it finds a node that is unmarked. It marks it but does not delete it. Subsequently, it is lazily deleted by a cleanup operation. This operation keeps the size of the stack in check by not allowing the size of the stack to increase beyond a factor of W as compared to the actual size. All our operations are wait-free and linearizable.

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BibTeXRIS

Seep Goel, Pooja Aggarwal, Smruti R. Sarangi. 2015-10-01. A Wait-Free Stack. https://arxiv.org/abs/1510.00116

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