NVMe is one of the most used terms in the IT industry today, but in reality, few people know what it is, and fewer customers are buying or using the technology. Why is this? NVMe (Non Volatile Memory Express) is very much an emerging technology - a storage technology, for both servers and storage arrays. All the major vendors are “getting ready” for it, it could be the technology for 2018.
What is NVMe?
Firstly, what NVMe isn’t - NVMe today is not storage media.
NVMe is actually an interface, which aims to reduce latency by eliminating the legacy storage stack, deliver greater parallelism and be the protocol for the next generation devices of the future. Today, most of the NVMe offerings in the market leverage the “interface” of NVMe and utilise 3D NAND (SSD) media, the next evolution of the media will deliver even more than today’s NVMe SSD combination – but more of this later.
NVMe is an interface, which replaces SAS/SATA/SCSI, has been created to overcome the limitations of these 30+ year old protocols, that were originally developed for hard disks (HDD) and tape drives. NVMe is the future, it takes advantage of the parallelism of modern day CPUs and SSDs to deliver superior performance that many organisations desire.
NVMe will provide access to the next generation storage media: Storage Class Memory (SCM), examples include Intel’s 3D XPoint. As SCM becomes generally available and used in combination with NVMe it will offer a dramatic reduction in latency and offer magnitudes of increase in performance IOPS versus NVMe with NAND SSD – it is predicted that this improvement will be comparable to the speed bump that occurred due to the transition from spinning disk and SSD.
Storage Class Memory will be the high speed, low latency medium that NVMe interface has been designed and has been waiting for – comparing a HDD and NVMe + SCM is similar to comparing the Wright brothers “Kitty Hawk” and a modern day jet fighter.
Deployment: Servers - today most of the leading server vendors are either offering or are planning to offer NVMe (interface) support. Dell EMC, for example, have announced and made available NVMe support on several of their 14th generation PowerEdge servers - NAND based SSD NVMe devices initially, with Storage Class Memory (SCM) devices as they become available.
Deployment: Storage Arrays – NVMe embedded into storage arrays is the obvious evolution, initially utilising the benefits of the interface with NAND SSD technology, and in future utilising SCM based media for the next performance boost. The more difficult evolution is the communication stack between these storage arrays and the servers – “NVMe over Fabrics”.
With the mass appearance of all-flash storage devices over recent years, the storage protocol stacks (FC, iSCSI, IP etc.) have been identified as the next potential bottleneck, and several vendors are working hard to bring a “next generation” stack to market. These next generation protocols are still yet to mature – standards, drivers, enterprise functionality such as multi-path are all in their infancy or still on the developer’s table.
A “next-gen” Fibre Channel based stack is much touted as the favourite, due to it’s “credits” based implementation, robustness and storage focus – but options such as iWARP and RoCE are also potential options too.
Whilst NVMe embedded in storage arrays looks like the earlier option, NVMe over Fabrics looks to be further away.
NVMe today, and in future with SCM based media offers lower latency than before and greater performance – several use cases are obvious: databases, transactional (OLTP), VDI - whilst “newer” use cases, such as HCI and software defined storage, will also leverage the NVMe performance benefits.
As a co-developer of the NVMe standards, staring in 2007, Dell EMC have an aggressive strategy around NVMe adoption in a variety of consumption models including: PowerEdge servers, storage arrays, software-defined storage (ScaleIO), converged and hyper-converged infrastructure solutions. If not already announced, it is expected that many of these offerings should be seen in the during 2018.
For further information or assistance, please email the Dell EMC team at Arrow by clicking here