Performance evaluation of dynamic network reconfiguration using Detour-UD routing

Abstract

Fault-tolerance is an emerging issue for massively parallel computers. This paper describes the performance impact of dynamic network reconfiguration protocols using a fault-tolerant, adaptive deadlock-recovery routing algorithm, Detour-UD, for k-ary n-cubes. We propose a scheme to specify unroutable packets by managing drain-flags in routing tables. We also propose two selective drainage protocols. One protocol drains the unroutable packets specified by the drain-flags after the reconfiguration process. The other protocol drains deadlocked packets to reduce the network load during the reconfiguration process. Our simulation results show that the first protocol helps reduce the number of drainage packets, and the second one keeps the network throughput during the reconfiguration process.