The Eighteenth International Conference on
Raleigh, North Carolina. September 12-16, 2009.
Oblivious Routing on On-Chip Bandwidth-Adaptive Networks
Myong Hyon Cho, Mieszko Lis, Keun Sup Shim, Michel Kinsy, Tina Wen and Srinivas Devadas
Oblivious routing can be implemented on simple router hardware, but network performance suffers when routes become congested. Adaptive routing attempts to avoid hot spots by re-routing flows, but requires more complex hardware to determine and configure new routing paths. We propose on-chip bandwidth-adaptive networks to mitigate the performance problems of oblivious routing and the complexity issues of adaptive routing.In a bandwidth-adaptive network, the bisection bandwidth of a network can adapt to changing network conditions. We describe one implementation of a bandwidth-adaptive network in the form of a two-dimensional mesh with adaptive bi-directional links, where the bandwidth of the link in one direction can be increased at the expense of the other direction. Efficient local intelligence is used to reconfigure each link, and this reconfiguration can be done very rapidly in response to changing traffic demands.We compare the hardware designs of a uni-directional and bidirectional link and evaluate the performance gains provided by a bandwidth-adaptive network in comparison to a conventional network under uniform and bursty traffic.