Rearchitected NVMe 2.0 Library of Specs From NVM Express

NVM Express, Inc. announced NVMe 2.0 family of specs.

They allow for faster and simpler development of NVMe solutions to support the increasingly diverse NVMe device environment, now including HDDs. The extensibility of the specs encourages the development of independent command sets like Zoned Namespaces (ZNS) and Key Value (KV) while enabling support for the various underlying transport protocols common to NVMe and NVMe-oF technologies.

“NVMe technology is the leading interface for SSDs, with overall worldwide enterprise SSD capacity expected to grow at a 43% CAGR into 2024,” said Jeff Janukowicz, research VP, IDC ^[1]. “NVMe architecture is designed for future SSD development and form factors, as we enter a new era in hyperscale and enterprise computing that drives digital transformation.“

“We have rearchitected the NVMe 2.0 library of specs to meet the evolving demands of the future of storage,” said Amber Huffman, president, NVM Express. “NVMe technology has unified client, cloud and enterprise storage around a common command set and architecture. Our technical work group has worked diligently to optimize the features of the NVMe 2.0 specs for diverse market segments, allowing for emerging use cases and opening new NVMe device types.“

NVMe 2.0 specs: New layout will propel industry development and momentum
The NVMe 2.0 library of specs consists of multiple documents, including the NVMe Base spec, Command Set specs (NVM Command Set spec, ZNS Command Set spec, KV Command Set spec), Transport specs (PCIe Transport spec, FC Transport spec, RDMA Transport spec and TCP Transport spec) and the NVMe Management Interface spec.

The new specs will facilitate the emerging NVMe device ecosystem, including enterprise and client SSDs, removable cards, compute accelerators and HDDs.

Key NVMe 2.0 features:

ZNS spec provides a zoned storage device interface that allows the SSD and host to collaborate on data placement. It permits data to be aligned to the physical media of the SSD, improving overall device performance and cost while increasing the media capacity that can be made available to the host.

KV Command Set provides access to data on an NVMe SSD controller using a key rather than a block address. KV allows applications to directly communicate with the drive using key-value pairs, avoiding the overhead of translation tables between keys and logical blocks.
Namespace Types provides a mechanism to allow an NVMe SSD controller to support the different command sets that are defined as part of the NVMe 2.0 release as well as a path for future command sets.
NVMe Endurance Group Management enables media to be configured into Endurance Groups, exposing granularity of access to the SSD and improving control.
Rotational media support enables support for HDD on NVMe with updates to features, management capabilities and other enhancements required for HDD support.
Multiple Controller Firmware Update defines behavior for firmware update on complex systems with multiple controllers.
Shutdown enhancements enables showdown control from enclosure management for simplified management of many drives at once.
Simple Copy Command copies data from one namespace in the drive, offloading the copy operations from multiple source LBAs to a single destination LBA.
32/64 bit CRC expands the protection information and data protection to 32 and 64 bits allowing for new types of metadata use cases.
Command Group Control prevents unintended changes after a system is provisioned and protects the system from unintentional or malicious changes.
NVMe 2.0 specs maintain backwards compatibility with previous NVMe gens.