Live migration of virtual machines (VMs) is an attractive technique for managing cloud computing platforms such as those for load balancing and maintenance of physical machines. However, the execution of live migration significantly consumes computational resources on the source and destination, thus causing migration noise that degrades the performance of the VMs collocated on these hosts during live migration. Migration noise lowers the total throughput of data centers and make it difficult to carry out live migration to handle unpredictable increases in workload such as sudden request bursts and flash crowds. This paper introduces SonicMigration, which is an approach to shortening total migration time by pruning the VM memory to be transferred. Preliminary experiments with our prototype implemented on Xen 4.1.0 and Linux 2.6.38 show the migration time with our prototype is up to 68.3% shorter than that for Xen-based live migration and it successfully reduces network traffic by up to 83.9%.