What are Zoned Namespaces (ZNS)?

The NVMe Zoned Namespaces (ZNS) interface is being developed by NVM Express. By dividing an NVMe namespace into zones, which are required to be sequentially written, ZNS offers essential benefits to hyper-scale organizations, all-flash array vendors and large storage-system vendors wishing to take advantage of storage devices optimized for sequential write workloads. ZNS reduces device-side write amplification, over-provisioning and DRAM while improving tail latency, throughput and drive capacity. By bringing a zoned-block interface to NVMe SSDs, ZNS brings alignment with the ZAC/ZBC host model already being used by SMR HDDs and enables a zoned-block storage layer to emerge across the SSD/HDD ecosystem.