Migration algorithm for Ceph block device cross clusters

The migration time of huge image files is vital to the efficiency of the whole-system on-line migration of a virtual machine. Therefore, optimizing the migration time has become a hot research area in virtual-machine migration technology. For virtual machines based on a distributed storage system, in which the more common one is Ceph block device, image data must go from the source storage nodes to the source client nodes, then to the destination client nodes, and finally to the destination storage nodes. This way ignores the benefit from the storage system to the migration. Given the above problems, a migration algorithm for Ceph block device cross clusters is effective. Image data go from the source storage nodes to the destination storage nodes in parallel, which uses the network of storage nodes.The result of the experiment shows that this algorithm shortens the migration time,and a few more storage nodes can improve efficiency of this algorithm.