Improving TCP responsiveness with connection history in data center networks

摘要

Data center networks are high-bandwidth, low-latency networks with clear-defined topology and busy internal data exchange traffic. TCP is widely used in data centers to transport data, however its default behavior during the flow initialization phase may be unsuitable for data center networks and affect the responsiveness of data transmission, especially when the flow is short. Considering that data center flows happen frequently but only between limited number of data center servers connected by a rather stable physical topology, in this paper we propose to use the RTT records from previous transmissions to help TCP calculate more suitable initialization parameters when a new flow starts, so as to avoid unnecessary lengthy timeouts that has heavy consequences on the overall performance, especially on short flows. Experiments show that our algorithms can indeed eliminate the long timeouts caused by early packet losses, and improve the responsiveness and stability of data transmission in a data center networking environment.