NEX: Virtual Machine Monitor Level Single System Support in Xen

Numerous approaches have been investigated to achieve single system image in order to simplify the complexity of programming and administration of cluster. This paper focuses on virtualization approach and presents NEX, a system of cooperative hypervisors with single system image support. NEX could provide a virtual SMP machine over cluster nodes. Commodity operating systems that support SMP could run across nodes through NEX in parallel. The approach is based on prior research on virtualization and distributed shared memory. This paper describes the design and implementation of NEX and gives a preliminary evaluation.