Page 20 - EE|Times Europe Magazine - December 2020

20 EE|Times EUROPE — The Memory Market

NVMe-oF Is Ready to Go the Distance

Virtual System Composition & Orchesration

Open Composabel API

HTTP CIM REST JSON
IETF DMTF ECMA

Western Digital’s approach to NVMe-oF has been intentionally agnostic and includes its own Open Composable architecture, launched
two years ago, which combines several industry standards to create the Open Composable API. (Source: Western Digital)

arrays’ high performance and low latency. “We see a lot of applications to reducing vendor lock-in, he said.
and early adopters around all-flash arrays,” he said. Today, SSDs are driving NVMe-oF adoption, said Rob Davis, vice
Western Digital also sees NVMe-oF as an ecosystem play. Earlier president of storage technology for the networking business unit at
this year, the company announced several interrelated offerings, Nvidia, an NVM Express member company. “Faster storage needs a
including a dual-port, third-generation Ultrastar DC SN840 NVMe faster network. Your SSD is getting faster, the PCI bus is getting faster,
SSD, along with its new OpenFlex Data24 NVMe-oF Storage Platform and the network that’s between the two is getting faster. It’s a really
to extend its performance and share disaggregated flash. good combination for the future, especially when you have these
The OpenFlex platform also incorporates the company’s RapidFlex huge data-hungry applications like machine learning and artificial
controllers to enable NVMe/NVMe-oF connectivity while being mind- intelligence.”
ful of power efficiency — capabilities that are the result of Western Longer term, Davis said, it’s conceivable that other persistent
Digital’s Kazan Networks acquisition. memories might use the NVMe specification, including 3D Xpoint. “We
Scott Hamilton, senior director for product management and already have Intel Optane SSDs that have been in production for multi-
marketing at Western Digital, said that the company’s approach to ple years that are taking full advantage of that low-latency stack.”
NVMe-oF has been intentionally agnostic but with the belief that NVMe-oF with TCP is also enabling the replacement of Serial
Ethernet will dominate the data center: “We think ultimately that’s Attached SCSI (SAS) as a means of scaling up enterprise storage arrays.
where the lowest cost and the greatest ubiquity will be.” At the same “It’s actually one of the main targeted use cases for NVMe over Fab-
time, Western Digital supports RoCE and plans to support TCP. A key rics,” said Davis. The other is a desegregated storage model, including
milestone for the company’s NVMe-oF support was its own Open hyperscale data centers, where most of the traffic is internal to the data
Composable architecture, launched two years ago. The architec- center. “They’re just scaling the flash independent of the CPUs, the
ture has several layers that provide different functions to support a DRAM, and compute,” he said. “They can access that flash anywhere
composable disaggregated infrastructure, combining several industry within a data center with standard networking equipment.”
standards to create the Open Composable API. Thomas Coughlin, president of Coughlin Associates, said that there
Hamilton said that the goal was to provide a consistent experience is increasing use of TCP with NVMe-oF due to TCP’s universality,
across different solutions, vendors, products, and users, potentially even though the early adoption was around Fibre Channel solutions.
reducing vendor lock-in and driving vendor-neutral solutions. Early “TCP-based networks are probably already going to get the biggest
adoption of NVMe-oF is driven by high performance and low latency, success,” he said.
and those early adopters are using RoCE to get there, he said, while In general, there are obvious use cases for NVMe-oF in storage sys-
TCP has the benefit of being less complex. tems and management, as well as computational storage, because the
Mark Miquelon, director for partner alliance engineering, data high-performance interface allows for coordination between memory
center systems at Western Digital, said that customers are selecting in different locations, whether facilities or racks, said Coughlin. There
NVMe SSDs when latency matters, and without NVMe-oF, there are are also likely to be some tie-ins with accelerator technology.
limitations in how many can be connected over PCIe. “With NVMe over NVMe-oF has a helping hand in the fact that TCP support has
Fabrics, we’re able to scale that out significantly,” said Miquelon. The been available for two years now, said Coughlin, while NVMe itself
impact on latency is minimal, he said, so applications can be scaled to is relatively mature. And he doesn’t foresee direct competition from
the size of the network. emerging architectures such as the emerging Compute Express Link
But in the real world, NVMe-oF doesn’t eliminate the potential for (CXL) or Gen-Z architectures. “All three of them are going to play a role
network congestion. There are going to be a lot of applications on the in storage development in the next few years,” he said. “There are a lot
same fabric trying to get data, possibly from the same SSDs or from dif- of players that are doing all three. Their objective is probably going to
ferent SSDs sharing the same fabric, Miquelon said. That’s why Western be to find the best way of using them together.”
Digital created its Compatibility Lab, which is open to anyone to under- Nvidia’s Davis sees Gen-Z being rolled into CXL, which has backing
stand these real-world scenarios and help customers bring fabric-based from Intel. “If you have Intel behind you, you’re in good shape,” he said.
products to market. “We’re looking at how the data behaves when the And like NVMe, CXL leverages PCIe, a mature, standardized technol-
fabric is congested,” he said. ogy with which everyone is comfortable. That spurs NVMe-oF adoption,
Miquelon cited another barrier: Even though the switch vendors are too, Davis said, allowing people to prepare for it even if they’re not
following standards, each one does it slightly differently, and they test ready to use it right away and not worry about being locked into a
with their own NICs. So the Compatibility Lab is also an environment proprietary technology. ■
for mixing and matching to create recipes that allow for good inter-
operability between different switch and NIC vendors and contribute Gary Hilson is a contributing editor for AspenCore.

DECEMBER 2020 | www.eetimes.eu