Research On Lossless Congestion Control Of Data Center Networks

In data centers,packet losses cause high retransmission delays,which is harmful to many real-time workloads.To prevent packet losses,the lossless fabrics have been deployed in many production data centers.However,when network congestion happens,the lossless fabric may cause tree saturation and then lead to a series of problems,which seriously degrade the performance of data center applications.Therefore,how to control the congestion in high-speed lossless data center networks is a challenging and significant problem.This paper introduces some typical congestion control schemes in high-speed lossless data center networks and classifies them into two categories: reactive and proactive.Based on the analysis of these surveyed schemes and the multi-path characteristic of data center networks,this paper designs and implements a multi-path credit-based proactive congestion control scheme named Multi-Path Credits(MPC).MPC proposes a multi-path credit reservation mechanism and an ECN-based credit rate control mechanism.The experimental results show that by means of the end-to-end proactive congestion control algorithm,MPC can keep near-zero queue of the switch and realize low queuing delay,further achieve packet lossless.Depending on the multi-path credit reservation mechanism,MPC can make full use of idle links in the network,maximize network bandwidth in the data center multi-path topology,and achieve rapid convergence and continuously high throughput.Based on the ECN-based dynamic credit rate control mechanism,MPC can solve the problems of low link utilization and unfair link sharing in parking lot topology and multi-bottleneck topology.