A distributed algorithm for detecting communication deadlocks

Abstract

A distributed system is an interconnected network of computing elements or nodes, each of which has its own storage. A distributed program is a collection of processes. Processes execute asynchronously, possibly in different nodes of a distributed system, and they communicate with each other in order to realize a common goal. In such an environment, a group of processes may sometimes get involved in a communication deadlock. This is a situation in which each member process of the group is waiting for some member process to communicate with it, but no member is attempting communication with it. In this paper, we present an algorithm for detecting such communication deadlocks. The algorithm is distributed, i.e., processes detect deadlocks during the course of their communication transactions, without the aid of a central controller. The detection scheme does not assume any a priori structure among processes, and detection is made "on the fly" without freezing normal activities. The proposed scheme is appropriate to be implemented within runtime support or kernel of distributed programming languages.