A Network-Friendly Disk I/O Optimization Framework in a Virtualized Cloud System

In a typical virtualized cloud system, network-attached storage (NAS) is the common technology for storing the disk image files of virtual machine (VM). Although the client/server model on NAS is more reliable and manageable, a concurrent accessing behavior from multiple VMs on the shared NAS server may exhaust the underlying network bandwidth, thus hurting the disk I/O performance of VMs. In this paper, we improve this problem by a set of optimizations, which are designed around bridging the semantic gap between the file system of VM and NAS server. The experimental result shows that our work can effectively reduce the network traffic between the NAS server and client. Meanwhile, the disk I/O performance of VMs can be also improved.