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Publications of SPCL

T. Hoefler, T. Schneider, A. Lumsdaine:

 Optimized Routing for Large-Scale InfiniBand Networks

(. Vol , Nr. , In 17th Annual IEEE Symposium on High Performance Interconnects (HOTI 2009), presented in New York, NY, pages , , ISSN: , ISBN: , Aug. 2009)


Point-to-point metrics, such as latency and band- width, are often used to characterize network performance. However, these metrics do not fully account for effects, such as network congestion, which influence the overall network performance. Many high-performance networks use static routing and thus the choice of routing algorithm can have a significant impact on overall network performance. In this paper, we analyze and compare practical and theoretical aspects of different routing algorithms that are used in today's large-scale networks. We show that widely-used theoretical metrics, as the edge-forwarding index or bisection bandwidth, are not an accurate predictor for the average case. We propose a new, practical, algorithm that globally balances the routes and therefore improves the effective bisection bandwidth of the network. Compared to the best algorithm in use today, our new algorithm shows an improvement in effective bisection bandwidth of 40% on a 724-endpoint InfiniBand cluster.


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  author={Torsten Hoefler and Timo Schneider and Andrew Lumsdaine},
  title={{Optimized Routing for Large-Scale InfiniBand Networks}},
  booktitle={17th Annual IEEE Symposium on High Performance Interconnects (HOTI 2009)},
  location={New York, NY},