Research And Implementation Of Online Migration Based Xen Virtualization Technology

With the advance of the construction of intelligent substation, virtualization technology in the application of intelligent substation has become very urgent. In the virtualization technology, online migration technology migrate a computer system(or virtual machine) from one physical host to another physical host. This technology not only ensures dynamic load balancing for each host, but also provides online upgrade and maintenance of the entire information system. Efficient and dynamically migrating virtual machines without affecting the normal service is the ultimate goal of virtual machine live migration. Currently live migration face to difficulties that is how to reduce migration time and downtime in ensuring the quality of service.Xen is a superior performance open source virtualization technology, and it supports para-virtualization and full-virtualization technology. And it can be applied in the intelligent substation with the complex application environments of redundant system configuration. Therefore, this paper focuses on the optimization of live migration in the Xen experimental platform, design to reduce the total migration time and downtime. At last, implement the design and test the effect of improved. The main contents of this paper are as follows:Study of Xen virtualization architecture, key technology, and read the source code to understand the Xen live migration technology implementation.Based on the above research, analyzes factors that affect the performance of the migration, then a reasonable framework for online migration in the traditional migration design, designed a new migration algorithm. Layered copy algorithm is based on the modified features dirty page is divided into different levels, different treatment for different levels of dirty pages, provide a migration efficiency; delayed copy algorithm that is focused primarily on the need for continuous transmission control dirty pages, to minimize unnecessary transmission, reduce migration time.Design the comparative experiments to verify the reasonableness and validity of the design of real-time migration algorithm. we draw conclusion: The improved migration algorithm can effectively reduce the total migration time and downtime.