|Authors||S. Reinemo, W. L. Guay, B. Bogdanski, O. Lysne and T. Skeie|
|Title||VFtree - a Fat-Tree Routing Algorithm Using Virtual Lanes to Alleviate Congestion|
|Afilliation||Communication Systems, Communication Systems|
|Publication Type||Talks, contributed|
|Year of Publication||2011|
|Location of Talk||Invited talk at the HPC Advisory Council Switzerland Workshop 2011, Lugano, Switzerland.|
A large number of clusters using InfiniBand is based on fat-tree topologies that can be routed deadlock-free using only one virtual lane. Consequently, all the remaining virtual lanes are left unused. In this talk we present an enhancement to the fat-tree algorithm that utilizes virtual lanes to improve performance when hot-spots are present. In a congested environment, results show that we are able to achieve throughput increases up to 38% on a small cluster and from 221% to 757% depending on the hot-spot scenario for a 648-port simulated cluster.