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Storage efficiency

ONTAP offers a wide range of storage efficiency technologies in addition to Snapshot copies. Key technologies include thin provisioning, deduplication, compression, and FlexClone volumes, files, and LUNs. Like Snapshot copies, all are built on ONTAP's Write Anywhere File Layout (WAFL).

  • Thin provisioning
    A thin-provisioned volume or LUN is one for which storage is not reserved in advance. Instead, storage is allocated dynamically, as it is needed. Free space is released back to the storage system when data in the volume or LUN is deleted.
  • Deduplication
    Deduplication reduces the amount of physical storage required for a volume (or all the volumes in an AFA aggregate) by discarding duplicate blocks and replacing them with references to a single shared block. Reads of deduplicated data typically incur no performance charge. Writes incur a negligible charge except on overloaded nodes.
  • Compression
    Compression reduces the amount of physical storage required for a volume by combining data blocks in compression groups, each of which is stored as a single block. Reads of compressed data are faster than in traditional compression methods because ONTAP decompresses only the compression groups that contain the requested data, not an entire file or LUN.
  • FlexClone volumes, files, and LUNs
    FlexClone technology references Snapshot metadata to create writable, point-in-time copies of a volume. Copies share data blocks with their parents, consuming no storage except what is required for metadata until changes are written to the copy. FlexClone files and FlexClone LUNs use identical technology, except that a backing Snapshot copy is not required.