Issue No. 02 - July-December (2008 vol. 7)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/L-CA.2008.8
Crispin Gomez Requena , Universidad Politecnica de Valencia , Valencia
Francisco Gilabert Villamon , U.P.V., Valencia
Maria Gomez , U.P.V., Valencia
Pedro Lopez , U.P.V., Valencia
Jose Duato , Universidad Politecnica de Valencia, Valencia
The fat-tree is one of the most widely-used topologies by interconnection network manufacturers. Recently, it has been demonstrated that a deterministic routing algorithm that optimally balances the network traffic can not only achieve almost the same performance than an adaptive routing algorithm but also outperforms it. On the other hand, fat-trees require a high number of switches with a non-negligible wiring complexity. In this paper, we propose replacing the fat--tree by a unidirectional multistage interconnection network (UMIN) that uses a traffic balancing deterministic routing algorithm. As a consequence, switch hardware is almost reduced to the half, decreasing, in this way, the power consumption, the arbitration complexity, the switch size itself, and the network cost. Preliminary evaluation results show that the UMIN with the load balancing scheme obtains lower latency than fat--tree for low and medium traffic loads. Furthermore, in networks with a high number of stages or with high radix switches, it obtains the same, or even higher, throughput than fat-tree.
Network topology, Network Architecture and Design, Fat-trees, Deterministic Routing, Multistage Interconnection Networks, Traffic Balancing, Butterfly Network, Cost-efficiency
P. Lopez, J. Duato, F. Gilabert Villamon, M. Gomez and C. Gomez Requena, "Beyond Fat--tree: Unidirectional Load--Balanced Multistage Interconnection Network," in IEEE Computer Architecture Letters, vol. 7, no. , pp. 49-52, 2008.