This allows DBAs to reclaim space on the storage array after data is deleted. ONTAP intercepts the zeros and deallocates the space from the LUN. The reclamation process is extremely fast because no data is being written within the storage system.

From a database perspective, the ASM diskgroup contains zeros, and reading those regions of the LUNs would result in a stream of zeros, but ONTAP does not store the zeros on drives. Instead, simple metadata changes are made that internally mark the zeroed regions of the LUN as empty of any data.

For similar reasons, performance testing involving zeroed data is not valid since blocks of zeros are not actually processed as writes within the storage array.