NVMe Zoned Namespaces (ZNS) Command Set Specification

Command Set

The individual command set specifications allow NVM Express to isolate and independently evolve command sets for emerging technologies such as Zoned Namespaces, Key Value and eventually computational storage. The NVMe specifications before NVMe 2.0 included all command set details. NVMe 2.0 separates these command sets into different specifications.

The NVMe Base specification defines the Admin Command Set, which provides essential administrative and management commands, including identify and get-log-page.

What is the Zoned Namespaces (ZNS) Command Set specification?

The NVMe Zoned Namespaces (ZNS) interface is a command set 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 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.