Quality-of-Service Provision for BXI3-Based Interconnection Networks

The ever-increasing demand for computational power and storage capacity has led to massive Supercomputers and Data Centers running highly parallel applications and services commonly utilized in fields such as Physics, Biology, Robotics, Medicine, or generative AI. The interconnection network is the backbone of these systems since it allows processing and storage nodes to communicate with high bandwidth and low latency, otherwise becoming the entire system bottleneck. These systems commonly run several applications simultaneously, which may have specific network requirements due to technical or contractual reasons. Indeed, the traffic flows from different applications are expected to need different bandwidth and latency levels predetermined before execution. Therefore, Quality of Service (QoS) has been a recurrent design aspect for high-performance interconnection networks, as it happens for different technologies, such as Slingshot (Cray) or InfiniBand (NVIDIA). In this regard, as far as we know, no proposals have been made yet to provide applications with QoS for the upcoming generation of BXI (BXI3). We propose using arbitration tables to assign different priorities to packets when they are injected by NICs or forwarded by switches. We have conducted simulation experiments to evaluate our proposal, comparing several QoS configurations using synthetic workloads. The obtained results show that the proposed QoS approach is efficient and feasible so that it can be applied to the upcoming BXI3.