EFFICIENT DATA MIGRATION IN HIERARCHICAL STORAGE MANAGEMENT SYSTEM

Embodiments provide a method, a system, and a computer program product for performing copy operations of one or more data units in a hierarchical storage management (HSM) system. The HSM system includes an upper layer and a lower layer. The upper layer includes multiple storage nodes having a grid configuration. The method comprises scheduling a copy operations of multiple data units each of which is stored in at least one of the multiple storage nodes such that loads on the copy operations are distributed among the multiple storage nodes in which the multiple data units are stored and copying the multiple data units to the lower layer in accordance with the scheduling.