Atiqul Mollah

Traffic Pattern-Based Adaptive Routing for Intra-Group Communication in Dragonfly Networks

The Cray Cascade architecture uses Dragonfly as its interconnect topology and employs a globally adaptive routing scheme called UGAL. UGAL directs traffic based on link loads but may make inappropriate adaptive routing decisions in various situations, which degrades its performance. In this work, we propose to improve UGAL by incorporating a traffic patternbased adaptation mechanism for intra-group communication in Dragonfly. The idea is to explicitly use the link usage statistics that are collected in performance counters to infer the traffic pattern, and to take the inferred traffic pattern plus link loads into consideration when making adaptive routing decisions. Our performance evaluation results on a diverse set of traffic conditions indicate that by incorporating the traffic pattern-based adaptation mechanism, our scheme is more effective in making adaptive routing decisions and achieves lower latency under low load and higher throughput under high load than the existing UGAL in many situations.

Random Regular Graph and Generalized De Bruijn Graph with

The Random regular graph (RRG) has recently been proposed as an interconnect topology for future large scale data centers and HPC clusters. An RRG is a special case of directed regular graph (DRG) where each link is unidirectional and all nodes have the same number of incoming and outgoing links. In this work, we establish bounds for DRGs on diameter, average

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-Shortest Path Routing

-shortest path length, and a load balancing property with

Fast Calculation of Max-Min Fair Rates for Multi-commodity Flows in Fat-Tree Networks

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Load-Balanced Slim Fly Networks

-shortest path routing, and use these bounds to evaluate RRGs. The results indicate that an RRG with

Rapid Calculation of Max-Min Fair Rates for Multi-Commodity Flows in Fat-Tree Networks

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A comparative study of SDN and adaptive routing on dragonfly networks

-shortest path routing is not ideal in terms of diameter and load balancing. We further consider the Generalized De Bruijn Graph (GDBG), a deterministic DRG, and prove that for most network configurations, a GDBG is near optimal in terms of diameter, average

Throughput Models of Interconnection Networks: The Good, the Bad, and the Ugly

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Modeling UGAL on the Dragonfly Topology

-shortest path length, and load balancing with a