An Enhanced CPU Scheduler for XEN Hypervisor to Improve Performance in Virtualized Environment

In Virtualization technology the CPU scheduling is crucial. How to adjust the virtual machine corresponding to the physical machine will affect the overall system performance. According to the Xen Credit Scheduler, each virtual CPU is asynchronously assigned to a physical CPU, but in the concurrent program it will result in considerable waste of CPU time. In this paper, a solution is proposed for the synchronization problem of a concurrent program. By modifying the Xen Credit Scheduler, threads in the concurrent program can be synchronized and the performance in concurrent workload is greatly enhanced. The waste of CPU time can be reduced and achieve higher throughput while keeping the design of the scheduler to be light weight, fair and efficient. With the proposed scheduler, more VMs can be deployed while achieving the same throughput, thus gain greater utilization of resources and better energy efficiency.