Requirements for deadlock-free, adaptive packet routing

Robert Cypher, Luis Gravano
1992 Proceedings of the eleventh annual ACM symposium on Principles of distributed computing - PODC '92  
This paper studies the problem of deadlock-free packet routing in parallel and distributed architectures. We present three main results. First, we show that the standard technique of ordering the queues so that every packet always has the possibility of moving to a higher ordered queue is not necessary for deadlockfreedom. Second, we show that every deadlock-free, adaptive packet routing algorithm can be restricted, by limiting the adaptivity available, to obtain an oblivious algorithm which is
more » ... algorithm which is also deadlock-free. Third, we show that any packet routing algorithm for a cycle or torus network which is free of deadlock and which uses only minimal length paths must require at least three queues in some node. This matches the known upper bound of three queues per node for deadlock-free, minimal packet routing on cycle and torus networks.
doi:10.1145/135419.135425 dblp:conf/podc/CypherG92 fatcat:jra6agoctrcypjsxbgzmmtguqi