A New Pre-copy Strategy for Live Migration of Virtual Machines

Live Migration, which moves a running virtual machine between different physical machines without disconnecting clients or applications, brings great flexibility in the cloud computing environment. The pre-copy strategy, as the main mechanism for the live migration, cannot work well when dirty memory pages are largely generated because of frequent update operations. In this paper, we propose a novel pre-copy strategy to reduce the total migration time and the total transferred data. The key idea is to compute the frequency of each dirty page based on historical and current statistics data. A dirty page will be transferred only when its transfer weight is not greater than a predefined threshold, otherwise its transfer will be delayed. The experiment results show that the optimized strategy can significantly reduce the total transferred data and the total migration time.