Temperature-sensitive storage efficiency was introduced in ONTAP 9.8 and was enabled automatically on newly created thin-provisioned AFF volumes. Compression is not achieved at the volume level anymo...Temperature-sensitive storage efficiency was introduced in ONTAP 9.8 and was enabled automatically on newly created thin-provisioned AFF volumes. Compression is not achieved at the volume level anymore, earlier compression savings were displayed through the df command's -S option which is deprecated going forward and will always show 0 for compression. On TSSE-enabled volumes, all compression savings are reflected at the aggregate layer.