Improving I/O performance of Xen hypervisors for solid state drives

Solid state drives (SSDs) are becoming increasingly popular in computing environment that employ virtualization. The Xen hypervisor is the most popular hypervisor for virtualization. In this paper, we discuss the performance of SSDs on the Xen hypervisor, show that the Xen I/O model causes performance degradation in SSDs, and analyze the reasons for the degradation. We then propose a new I/O processing method, clustering of fragmented I/O requests, which improves the I/O performance of SSDs. The evaluations indicate that our proposed method improves the I/O performance by as much as 7%.