Mcredit2: Enhanced High-Performance Xen Scheduler via Dynamic Weight Allocation

Generally, operating only a single host on a single server results in hardware underutilization. Thus, hypervisors (e.g., Xen) have been developed to allow several hosts to operate on a single server. The Xen hypervisor provides processor schedulers (e.g., Credit and Credit2 schedulers) to assign processors to each host. The Credit2 scheduler provides work assurance to the domain relative to latency and it evenly assigns processors to each domain. In addition, the Credit2 scheduler can assign a weight value to each host. A greater host weight value allows processors to be assigned to a host for longer periods. However, the Credit2 scheduler shows poorer performance than the basic Credit scheduler, which utilizes idle processors. In this paper, we propose the Mcredit2 scheduler, which improves the Credit2 scheduler. The Credit2 scheduler takes no action when the load on a specific domain causes increased processor usage. The proposed Mcredit2 scheduler allows a domain to quickly process loads by temporarily assigning a greater weight value to a host with high processor usage. In addition, we introduce a processor monitoring tool that visualizes the processor usage