Virtualization is widely adopted by the data centers, in order to fulfill the high demand for resources and for their proper utilization. For system management in these virtualized data centers virtual machine live migration acts as a key method. It provides significant benefit of load-balancing without service disruption. Along with the various benefits virtual machine live migration also imposes performance overhead in terms of computation, space and bandwidth used. This paper analyzes the widely used precopy method for virtual machine live migration and proposes the two fold optimization of precopy method for virtual machine live migration. In the first phase, the proposed two fold precopy method reduces the amount of data sent in first iteration of precopy method. Second phase restricts sending of similar data iteratively in each subsequent iterations of precopy method by identifying frequently updated pages and keeps it till the last stop and copy iteration. In this way it reduces total migration time and total amount of data transferred. The proposed two fold precopy method is compared with precopy method and simulation results show the performance improvement of a virtual machine live migration in terms of total migration time and total amount of data transferred.