Wait-free k-set agreement is impossible: the topology of public knowledge

Proceedings of the twenty-fifth annual ACM symposium on Theory of Computing Pub Date : 1993-06-01 DOI:10.1145/167088.167122

M. Saks, Fotios Zaharoglou

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引用次数: 389

Abstract

In the classical consensus problem,each of n processors receives a private input value and produces a decision value which is one of the original input values,with the requirement that all processors decide the same value. A central result in distributed computing is that,in several standard models including the asynchronous shared-memory model,this problem has no determinis- tic solution. The k-set agreement problem is a generalization of the classical consensus proposed by Chaudhuri (Inform. and Comput.,105 (1993),pp. 132-158),where the agreement condition is weak- ened so that the decision values produced may be different,as long as the number of distinct values is at most k .F or n>k ≥ 2 it was not known whether this problem is solvable deterministically in the asynchronous shared memory model. In this paper,we resolve this question by showing that for any k

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无等待的k集协议是不可能的:公共知识的拓扑结构

在经典的共识问题中，n个处理器中的每一个都接收到一个私有输入值，并产生一个决策值，该决策值是原始输入值之一，要求所有处理器决定相同的值。分布式计算的一个主要结果是，在包括异步共享内存模型在内的几个标准模型中，这个问题没有确定的解决方案。k集共识问题是Chaudhuri (Inform)提出的经典共识问题的推广。与第一版。105(1993),页。(132-158)，其中一致性条件弱，使得产生的决策值可能不同，只要不同值的个数不超过k . f或n>k≥2，则不知道该问题在异步共享内存模型中是否确定性可解。在本文中，我们通过证明对于任意k

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Proceedings of the twenty-fifth annual ACM symposium on Theory of Computing

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