NVM Express (NVMe) Specification
NVMe is the interface for all modern SSDs. Understanding queue depth, namespace management, ZNS for log-structured workloads, and NVMe-oF for disaggregated storage is required for storage system design, cloud storage backends, and OS I/O subsystem work.
What It Defines
Defines the host controller interface and command set for PCIe and Fabrics-attached solid-state storage. NVMe 2.0 introduces command set disaggregation: NVM command set (read/write/flush/dataset-management), Zoned Namespace (ZNS) for SMR/ZNS drives, and Key-Value (KV) command set. Core architecture uses submission/completion queue pairs with doorbell registers for low-latency I/O. NVMe over Fabrics (NVMe-oF) extends the protocol over RDMA (RoCE/iWARP), TCP, and Fibre Channel for networked storage. Also covers end-to-end data protection (T10 DIF/PI format) and namespace management.
Canonical (Normative)
Convenient (Practical)
Industry consortium (Intel, Samsung, Seagate, Western Digital, Micron, KIOXIA) that owns the NVMe specification — the host controller interface and command set for PCIe and Fabrics-attached solid-state storage. NVMe 2.0 introduces command set disaggregation (NVM, ZNS, KV), NVMe-oF (over Fabrics via RDMA/RoCE/TCP/FC), and the computational storage specification.
Related Specs
PCIe is the universal high-speed peripheral bus. Understanding lane width, bandwidth, BAR mapping, and MMIO is essential for GPU compute (CUDA/ROCm), NVMe performance tuning, SR-IOV NIC virtualization, and DPDK kernel-bypass networking.