1. A method for migrating a group of virtual machines (VMs) from at least one source platform to at least one destination platform, comprising: pre-copying contents of memory associated with each source VM to memory associated with a corresponding respective one of the destination VMs such that copying the memories of all source VMs to be migrated is completed within a pre-copy convergence time window; stunning each source VM after completion of the pre-copying contents of the memory associated with it; checkpointing the stunned source VM and transferring its checkpoint to the destination platform; transmitting from the destination platform to the source platform a handshake message indicating readiness to begin execution of at least one of the destination VMs on the destination platform; receiving from the source platform an acknowledgement message indicating readiness to transfer execution from at least one source VM to the corresponding destination VM; and starting execution of each destination VM for which the acknowledgement message has been received.