An optimized approach to virtualize an execution environment for windows applications

Application virtualization is to isolate applications from the host system and from other applications in an operating system. This paper focuses on virtualization strategies and optimized strategies in our optimized approach to virtualize an execution environment for windows applications. Since the resources, such as registry, file and system object, play different roles during the runtime, different virtualization strategies are adopted. Every resource is divided into different groups which have different priorities according to the attributes and functions of the groups during the runtime. Registry virtualization is to rewrite the system calls, and file visit virtualization and system objects virtualization are to rewrite the parameters of the system calls. Moreover, because of the complicated scenarios during the runtime, our approach adopts three main optimized strategies, which are synchronization methods, parameter buffer and optimized methods of private registry. Synchronization methods are used to improve the performance of multi-threads and multi-processes created by applications. Parameter buffer is used to reduce the allocation operation when parameters are required to rewritten in the high frequent system calls made by applications, usually tens of thousands of times per run. Optimized methods of private registry are used to speed up the rewritten system calls for the virtual registry. Through the optimized strategies, the average overhead is reduced to 30% and the absolute value of time-consuming is acceptable.