Improving Network I/O Virtualization for Cloud Computing

Virtualization is a key technology to enable cloud computing. It enhances resource availability and offers high flexibility and cost effectiveness. However, the driver domain-based model for network I/O virtualization exhibit poor networking performance. In this paper, we evaluate the networking performance of VMs based on Xen. The I/O channel transferring packets between the driver domain and the VMs is shown to be the bottleneck. To overcome this limitation, we proposed a packet aggregation-based mechanism to transfer packets from the driver domain to the VM. Experimental performance evaluation showed that our proposal allows the VMs throughput to scale up at line rates. Furthermore, we studied the impact of the aggregation on the packets delay. For this purpose, we proposed a system modeling based on queuing theory. The proposed model allowed us to dynamically tune the aggregation mechanism to achieve the best tradeoff between the packets delay and throughput. The proposed I/O virtualization model henceforth satisfies the infrastructure providers to offer cloud computing services.