SP-TCP: Scheduling Perceived TCP in Virtualized Datacenters

Virtualization technology has played an increasingly important role in modern datacenters and cloud computing. With the rapid development of hardware, the capability of single physical server has become more and more powerful. So it has been a trend that deploying multiple VMs (Virtual Machines) on a single physical host, which is so called virtual machine consolidation. High degree of VM consolidation will likely make VMs experience a long scheduling delay, which would in turn affect the standard TCP round-trip time(RTT) measurement and further more lead to TCP RTO(Retransmission Timeout), a symbol of network congestion. In this paper, we present the design, implementation, and evaluation of SP-TCP, a Scheduling Perceived TCP. SP-TCP will detect the schedule event and notify all those related VMs, including senders and receivers. Our evaluation of a SP-TCP prototype on Xen shows that SP-TCP has a better performance than standard TCP.