A Delay Estimation in HPC Wormhole Switching Based on Network Calculus

Abstract

Wormhole switching technology is widely used in High Performance Computer (HPC) systems. The delay estimation of wormhole switching is mainly focused on average packet delay. But in order to provide Quality of Service (QoS) guarantees, we should analyze the end-to-end delay bound of wormhole switching. Based on models of Credit Stall and Switch Allocation Stall, we use arrival curve to constrain the arrival flow, and service curve to describe the service ability which system can guarantee to the arrival flow. Together with some fundamental theorems in Deterministic Network Calculus, we give the delay upper bound of flows in 3D-Torus network.