Evaluation of wormhole routed networks under hybrid traffic loads

The authors investigate the performance of wormhole-routed networks under hybrid traffic loads to examine the impact of long and short messages on each other. The short messages not only experience increased average latency but also experience a large increase in the variance of that latency. The negative performance impact of long messages increases proportionally with both the fraction and size of the long messages. The authors also explore two techniques, virtual lanes and adaptive routing, to improve network performance under the hybrid traffic loads. Performance losses due to long messages can be dramatically reduced with either technique. The two techniques are complementary, so employing them simultaneously yields the best performance, virtually eliminating performance losses experienced by short messages. This means that packetization may not be necessary in such networks.