Beginning with ONTAP 9.10.1, the volume-level storage efficiency modes default and efficient are supported for AFF systems only. These modes provide a choice between file compression (default), which is the default mode when creating new AFF volumes, or temperature-sensitive storage efficiency (efficient), which enables temperature-sensitive storage efficiency. You can use the volume efficiency modify command to change the storage efficiency mode for an AFF volume from default to efficient, or you can set an efficiency mode when volume efficiency is not already set.