What it is: NVMeOF, or Non-Volatile Memory Express Over Fabrics, is a storage networking protocol. It pairs NVMe, a protocol for rapid access to local solid-state drives, with RDMA, Remote Direct Memory Access, a technology enabling fast information transfer over a network fabric, that is, a network topology enabling connections between multiple endpoints. This can be accomplished with a variety of different connection technologies, such as Ethernet, Fiber Channel, or InfiniBand, in combination with specific NVMeOF-enabled hardware.
What it does: NVMeOF improves storage performance within the data center, by alleviating a number of bottlenecks. The first bottleneck is in local storage performance, which is addressed by NVMe. However, that alone, in a networked setting, simply moves the bottleneck to the network, which will not typically communicate as quickly with remote storage. With the addition of Remote Direct Memory Access, NVMeOF takes care of that issue, resulting in unprecedentedly fast data transfer.
Why it matters: Many limitations in computing performance are due to data transfer bottlenecks rather than processing speed. And, while storage performance has increased 100x in the last five years, it hasn’t always been possible to extend that performance over networked systems relying on remote memory storage. NVMEoF makes this possible, with the potential to increase application performance significantly.
What to do about it: Unless performance in on-premise data centers is an issue in your enterprise, it’s not necessary to investigate NVMEoF technology. If it is an issue, it is worth asking data center infrastructure architects if they have considered deploying NVMEoF. Note that this technology is still in its infancy, and thus can be expensive and specialized.
- Higher application performance leads to better user experiences
- Potential for new use cases that benefit from increased data transfer speeds
- Faster transfers make data backup and disaster recovery faster
- Takes advantage of existing solid-state drive technology
- Relatively new technology, leading to a lack of choice, early adopter prices, and potential implementation difficulties
- Incompatible with older, spinning disc drive technologies
- Taking full advantage would require an overhaul of existing connectivity
NVMeOF is, as aforementioned, a marriage of NVMe technology with a network fabric. The latter half of the pairing matters; which fabric is used determines a large part of the implementation benefits and challenges. For example, NVMe over fiber channel, or FC, is relatively easy to scale, but potentially isn’t as fast as NVMe over InfiniBand, a more expensive and less scalable technology.
As of early 2020, NVMeOF adoption is not widespread. In 2019, only 6.5% of enterprises surveyed by storage firm LINBIT have connected over half of their environment with NVMe, a number necessarily lower than those who have adopted NVMeOF. However, many analysts project that NVMeOF will soon be commonplace, and thus will become the standard required to maintain competitive performance.