Auto-tiering is a quality of storage service feature that enables logical volumes or LUNs to span different tiers of storage and transparently move portions of the logical volume between tiers of storage to minimize storage costs and deliver consistent performance and throughput. The movement of sub-LUNs between tiers is managed by auto-tiering algorithms and/or policy. This makes it practical to reduce the storage costs of applications without redesigning them to make them storage-aware, and it avoids the onerous task of doing data classification. Typical implementations support storage tiers built with solid-state disks (SSDs), Fibre Channel (FC) or Serial-Attached Small Computer System Interface (SAS SCSI), and Serial Advanced Technology Attachment (SATA) or nearline disks, and may include restrictions on the movement of sub-LUNs between different tiers of storage.