Some introduction about Full File Clone which belonged to VAAI NAS Primitives

Full File Clone
Full File Clone, or Full Copy, is similar to the Extended Copy (XCOPY) hardware acceleration primitive provided
for block arrays. This primitive enables virtual disks to be cloned by the NAS device rather than by using the
Data Mover, which consumes ESXi host CPU and memory resources as well as network bandwidth. There is one
noticeable difference between this primitive and the XCOPY primitive on block storage: This primitive cannot be
called for Storage vMotion operations, which continue to use the Data Mover. Only virtual machines that are
powered off and then migrated can offload to the storage array by using this primitive. The Storage vMotion
restriction aside, the benefit is that cold clones or “deploy from template” operations can be offloaded to the
storage hardware, and this reduces the resource consumption of the ESXi host.