Tuning high flow concurrency for MPTCP in data center networks

Abstract

In the data center networks, multipath transmission control protocol(MPTCP) uses multiple subflows to balance traffic over parallel paths and achieve high throughput. Despite much recent progress in improving MPTCP performance in data center, how to adjust the number of subflows according to network status has remained elusive. In this paper, we reveal theoretically and empirically that controlling the number of concurrent subflows is very important in reducing flow completion time (FCT) under network dynamic. We further propose a novel design called MPTCP_OPN, which adaptively adjusts the number of concurrent subflows according to the real-time network state and flexibly shifts traffic from congested paths to mitigate the high tail latency. Experimental results show that MPTCP_OPN effectively reduces the timeout probability caused by full window loss and flow completion time by up to 50% compared with MPTCP protocol.