A diagonal cabling approach to data center and HPC systems

Low cable delay becomes a critical concern in High Performance Computing systems and high-density Data Centers since the switch delay becomes very low, e.g., 40 ns per switch, as the technology advances. The cable delay almost corresponds to the cable length. It significantly requires a short total end-to-end cable length when deploying a logical topology into a physical cabinet layout in a server room. Recent works illustrate that the problem of mapping any topology onto the floor plan with an efficient cable length can be modeled and solved as an optimization problem. This approach based on the Manhattan cabling method, with which the cables are organized into several horizontal and vertical pathways and the length of each cable becomes Manhattan distance. To reduce the aggregate cable length, we aggressively take the diagonal cabling method by increasing the number of directions on a surface. The analysis results with different topologies show that our approach can reduce the total cable length by up to 11%, which leads to 7% reduction of network latency.