An Interrupt Scheduling Mechanism of Virtual Network Interface Card for Xen-Based System

As one of typical paravirtualization hypervisors, Xen has received widespread attentions especially its scaling capability under some kinds of workload. In this paper, we focus on the problem that the most CPU resources are occupied by frequent interrupt from the NIC(Network Interface Card) and it will cause bottleneck of the system for Xen. To alleviate this problem, this paper proposes an adaptive interrupt latency scheduling mechanism based on XEN, which use the polling or interrupt method in accordance with the queue length of virtual buffer without supplementing any additional processing unit. Also, the method can guarantee different quality of service to some extent by means of the definition of the two types of priority virtual buffers. Simulation results show that the mechanism can reduce CPU overhead significantly and improve system performance effectively.