Embodiments provide for a primary storage array having multiple storage tiers. The multiple storage tiers include one or more performance tiers and at least one deduplicated storage tier storing deduplicated data. One embodiment provides for a data storage system including a first storage tier including a first set of storage devices; a second storage tier including a second set of storage devices, the second storage tier including deduplicated data; and a quality of service (QoS) manager to manage data migration between the first storage tier and the second storage tier, the QoS manager to maintain deduplication statistics for the deduplicated data, wherein the QoS manager, based on the deduplication statistics, is to partially migrate a data extent between the first storage tier and the second storage tier, the data extent including data stored at a range of storage addresses.