Virtual Machines with Sharable Operating System
Virtualization technologies commonly known as Cloud model enable the execution of multiple virtual machine instances (VMs) with different operating systems (OSs) on the same physical host. Each VM instance functions independently as an isolated system with its own physical resources, OS copy and applications. There is only a limited number of currently available and widely used OSs used by most of the running VM instances; it is wasteful to store all the VM images with virtually the same common OS code. It is also inefficient in terms of performance and system resources utilization to virtually clone the entire image each time a new VM instance is provisioned. In addition, performing OS updates and patches are complicated, tedious and error prone since not only the stored images need to be updated, all the running VM instances must be properly refreshed. More importantly, faster provisioning of VM instances in respond to workload changes is critical to the successful operation of Cloud service providers. In this paper, we show our exploration work to address these performance issues by using a common, sharable operating system approach which provides run-time on-demand operating system components to individual VM instances in Cloud environment. This new approach allows optimized VM image storage, faster VM provisioning and efficient OS updates with minimum interruption.