Cache isolation and thin provisioning of hypervisor caches

Server virtualization has enabled resource consolidation and has minimized the need for additional and expensive hardware. Server virtualization has been widely deployed in a lot of organizations, because of the attractive benefits it offers like minimal hardware, cost effective resource consolidation, easier management and maintenance of hardware resources and so on. Many cloud service providers have offloaded processing capabilities to virtual servers in their data centers instead of using multiple physical servers which are very expensive these days. When such a virtualized server setup is connected to disk arrays, latency of data access becomes prominent. In order to minimize the response time of application requests on the virtual servers and make efficient utilization of cache, a dynamic caching mechanism is proposed by the authors on the hypervisor. The caching mechanism proposed in the research is different, in the sense that, it is an isolated, unshared and dynamic cache, where caching is done on the hypervisor instead of the virtual machines. The dynamic cache allocation algorithm enables thin provisioning of the hypervisor cache and leads to efficient cache utilization. Experimental results obtained using the thin provisioning algorithm look promising in terms of reducing the response time and efficiently utilizing the available cache.