Research and simulation of adaptive routing mechanism in InfiniBand network

InfiniBand interconnect network is widely used in parallel computing. Network adapter (HCA) is one of the necessary hardware components for architecture deployment. With the expansion of nodes in parallel computing system, InfiniBand network may have higher performance requirements. However, the current InfiniBand network uses deterministic routing, and adaptive routing can be introduced to meet higher requirements. Because the original InfiniBand protocol is strictly sequence-preserving, adding adaptive routes to the network improves performance but requires out-of-order rearrangement of network cards, which requires a certain cache capability. In this paper, the function extension of InfiniBand protocol is designed to realize the adaptive function and complete the modeling and simulation. Two indexes related to out-of-order are also designed in this paper, and the direct influence of adaptive routing on packet out-of-order and network adapter buffer depth is studied from many aspects. Through the simulation of the above system, the experimental result of All-to-All communication between model nodes shows that under the Greedy and RoundRobin adaptive port selection algorithms, the buffer depth required by the network card is 61 and 62 2KB of packet space, respectively. This provides an estimate of the buffer that the network card needs to handle out-of-order packets.