Hemlock : Compact and Scalable Mutual Exclusion

Dave Dice; Alex Kogan

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arXiv · 2102.03863

Hemlock : Compact and Scalable Mutual Exclusion

Dave Dice·Alex Kogan

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Abstract

We present Hemlock, a novel mutual exclusion locking algorithm that is extremely compact, requiring just one word per thread plus one word per lock, but which still provides local spinning in most circumstances, high throughput under contention, and low latency in the uncontended case. Hemlock is context-free -- not requiring any information to be passed from a lock operation to the corresponding unlock -- and FIFO. The performance of Hemlock is competitive with and often better than the best scalable spin locks.

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Dave Dice, Alex Kogan. 2021-02-07. Hemlock : Compact and Scalable Mutual Exclusion. https://arxiv.org/abs/2102.03863

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