The drinking philosophers problem

Abstract

The problem of resolving conflicts between processes in distributed systems is of practical importance. A conflict between a set of processes must be resolved in favor of some (usually one) process and against the others: a favored process must have some property that distinguishes it from others. To guarantee fairness, the distinguishing property must be such that the process selected for favorable treatment is not always the same. A distributed implementation of an acyclic precedence graph, in which the depth of a process (the longest chain of predecessors) is a distinguishing property, is presented. A simple conflict resolution rule coupled with the acyclic graph ensures fair resolution of all conflicts. To make the problem concrete, two paradigms are presented: the well-known distributed dining philosophers problem and a generalization of it, the distributed drinking philosophers problem.