DC-Vegas: A Delay-Based TCP Congestion Control Algorithm for Datacenter Applications

TCP congestion control in datacenter networks is very different from in traditional network environments. Datacenter applications require TCP to provide soft real-time latency and have the ability to avoid incast throughput collapses. To meet the special requirements of datacenter congestion control, numerous solutions have been proposed, such as DCTCP, D2TCP, and D3. However, several deployment drawbacks, including significant modifications to switch hardware, the Operating System protocol stack, and/or upper-layer applications, as well as switch ECN requirements, which are not always available in already existing datacenters, limit deployment of these solutions. To address these deployment problems, in this paper, we proposed a delay-based TCP algorithm for datacenter congestion control, namely DC-Vegas. DC-Vegas combines the performance advantages of DCTCP with the deployment advantages of delay-based TCP Vegas. DC-Vegas can meet both soft real-time and incast avoidance requirements of datacenters, requiring minimal deployment modification to existing datacenter hardware/software (with only sender-side update and without ECN requirements). Experimental results obtained using the real datacenter test bed and an ns-2 simulator demonstrate that DC-Vegas has similar performance with the state-of-the-art Data Center TCP algorithm.