“…For example, some work has focused on I/O performance improvement by tuning I/O related parameter [11], [13], [17], [25], [26], [32], [39], such as TCP Segmentation Offload (TSO), network bridging. Recently, some study showed that performance interference exists among multiple virtual machines running on the same physical host due to the shared use of computing resources [5], [23], [36], [37] and the implicit resource scheduling of different virtual machines done by VMM in the privileged driver domain [19]. For example, in current Xen implementation, all the I/O requests have to be processed by the driver domain, and Xen does not explicitly differentiate the Dom 0 CPU usage caused by I/O operations for each guest domain.…”