ODX copy offload must be enabled if you want to migrate virtual machine files or export and import database files directly from source to the destination storage location without sending data through the application servers. There are certain requirements that you must understand about using ODX copy offload with SQL Server and Hyper-V over SMB solutions.
Using ODX copy offload provides a significant performance benefit. This CIFS server option is enabled by default.
The default is to configure IDE disks, but ODX copy offload does not work when guests are migrated if disks are created using IDE disks.