Wavelength-routing interconnect "Optical Hub" for parallel computing systems

To solve the inter-node bandwidth bottleneck in parallel computing systems, we propose a wavelength-routing inter-node interconnect "Optical Hub". The physical topology of Optical Hub is star network, which leads to advantages in term of its throughput, size, energy consumption and life-time cost. The logical topology is full-mesh network, which leads to advantages in term of its latency and reliability. We introduced multi-path routings, which expand the effective bandwidth with the full-mesh topology such as Optical Hub, by replacing conventional MPI functions with our wrapper functions. We simulated execution time of parallel benchmarks on the parallel computing system with Optical Hub using parallel computing simulator SimGrid. As a result, we have confirmed that the parallel computing system with Optical Hub can achieve higher performance and lower energy consumption than conventional ones. We also examined the scalability of Optical Hub and showed that recursive hierarchical configurations of Optical Hub can save cable count drastically in case of large number of nodes against Dragonfly networks.