Abstract
As supercomputers have reached nearly 300,000 cores with 2 petaflops in Linpack performance in June 2010, energy consumption and temperature control are posing a developmental bottleneck. We retrospectively and comparatively examine all of the available data contained in the Green500 list that launched in November 2007, and the Top500 list, and propose a novel representation and analysis of the data, highlighting major evolutionary trends.With these new insights, we introduce a new technique for generating more efficient networks by systematically interlacing bypass rings to torus networks (iBT networks). The resulting network can improve the original torus network by reducing the network diameter, node-to-node distances, and by increasing the bisection width without increasing wiring and other engineering complexity. We present and analyze the statement that a 3D iBT network proposed by our technique outperforms 4D torus networks of the same node degree. We found that interlacing rings of sizes 6 and 12 to all three dimensions of a torus network with meshes 30 30 36 generates the best network of all possible networks, including 4D torus and hypercube of approximately 32,000 nodes. This demonstrates that strategically interlacing bypass rings into a 3D torus network enhances the torus network more effectively than adding a fourth dimension, although we may generalize the claim. We also present a node-to-node distance formula for the iBT networks.
