HNCC: Host-Network Collaborative Congestion Control for RDMA

Le résumé fourni par la source

Driven by the rapidly growing demands of modern applications, RDMA technology has been widely adopted in cluster networks, including high-performance computing (HPC) systems and datacenters. However, the high-speed, kernel-bypass nature of RDMA presents significant challenges for congestion control (CC). On one hand, since most RDMA operations are offloaded to the RDMA network interface card (RNIC), software-based CC struggles to regulate packet transmission effectively. On the other hand, RDMA workloads are dominated by short messages, making it difficult for both reactive and proactive CC protocols to manage congestion in a timely and effective manner, posing risks to network application QoS. Despite these challenges, proactive and reactive CC protocols each have distinct strengths, and combining them offers a promising research direction. This paper proposes an endpoint-network collaborative congestion control protocol (HNCC) that integrates proactive endpoint congestion control with reactive network monitoring and adjustment to achieve precise and rapid congestion management. HNCC introduces a novel reservation mechanism embedded within the RDMA protocol to prevent endpoint congestion while efficiently mitigating in-network congestion by dynamically adjusting the data injection rate based on network trend analysis. HNCC is offloaded to the RNIC, ensuring that its traffic scheduling is timely and effective. Extensive load testing across various scales shows that HNCC achieves performance comparable to state-of-the-art CC protocols in datacenter workloads and reduces the average flow completion time (FCT) by 5 − 56% under HPC workloads.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.