Proportional Disk I/O Bandwidth Management for Server Virtualization Environment

Many virtual machines are operated concurrently on a same physical machine. And service running on each virtual machine has different I/O requirement and priority. But, we can´t guarantee that it has proper I/O bandwidth, because the I/O of virtual machine is treated as that of a process in normal system and there is no means to manage the I/O bandwidth for virtual machine. Therefore, we are hard to allocate I/O bandwidth to several virtual machines equally or discriminately. To solve the upper described problems, we propose a virtual machine-aware proportional share queuing scheduler, VM-PSQ, in server virtualization environment. To do that, we designed virtual machine unit scheduler and adopted the concept of time slice and schedule token to support the proportional share of I/O bandwidth. It recognizes each virtual machine I/O as independent system I/O. It enables us to allocate I/O bandwidth among many virtual machines equally or discriminately according to service priority or I/O requirement. This can make a good use of limited I/O bandwidth and guarantee the performance of specific virtual machine.