Obtaining the optimal configuration of high-radix Combined switches

• We describe an alternative (C-switches) for building high-radix switches.
• We define a methodology for determining the optimal configuration of C-switches.
• We apply three search techniques to every C-switch in the network.
• Application of our methodology to a case study and several traffic patterns.
• We run a performance evaluation to confirm the efficiency of the considered algorithms.

High-radix switches reduce network cost and improve network performance, especially in large switch-based interconnection networks. However, there are some problems related to the integration scale to implement such switches in a single chip. An interesting alternative for building high-radix switches consists of combining several current smaller single-chip switches to obtain switches with a greater number of ports. A key design issue of this kind of high-radix switches is the internal switch configuration, specifically, the correspondence between the ports of these high-radix switches and the ports of their smaller internal single-chip switches. In this paper we use artificial intelligence and data mining techniques in order to obtain the optimal internal configuration of all the switches in the network of large supercomputers running parallel applications. Simulation results show that using the resultant switch configurations, it is possible to achieve similar performance as with single-chip switches with the same radix, which would be unfeasible with the current integration scale.