Reliability optimization of virtual machine monitor Xen

Optimization study was done on the Xen which was open and mainstream virtual monitor machine. Theories including Communicating Sequential Processes ( CSP) and software architecture were utilized to formalize architecture for block device in Xen. Design rules were proposed to constrain concurrent interactions among components of architecture for block device. Therefore, deadlocks were prevented in theory and the reliability was improved. With the guide of the design rules, the related programs were overhauled and revised. Preliminary experiments indicate that I /O throughput aroused by the overhaul is reduced. However, reliability of the system is enhanced. The optimization is still valuable.