ARM-based server processor from AMD lacks Intel SoC clout

Advanced Micro Devices is in the process of developing its first ARM-based server SoC. At the time of this writing, only three relatively small companies have publicly agreed to use the A1100, aka Seattle, mainly in storage and communications appliances. In fact, and one analyst said the chip will not compete directly with the Xeon server processors from Intel.

The 64bit chip was among the early examples of a running ARM-based server processor from a major chip maker. AMD hopes the A1100 powers platforms for building out the software ecosystem for ARM servers.

The 32W chip runs at 2GHz and uses eight ARM A57 cores, 4Mbytes L2 cache and supports DDR4 memory at up to 1,866MHz as well as support for two Gbit Ethernet controllers. Since it was first announced more than a year ago rivals including Applied Micro, Broadcom, Cavium, Huawei and Qualcomm have raised their sights, announcing plans for ARM-based server processors in FinFET processes using dozens of cores.

"The 28nm Seattle is not a competitive server processor relative to Intel's 22nm and 14nm offerings such as the Xeon E3 and Xeon D," said David Kanter, an analyst with The Linley Group and Real World Technologies. "The power efficiency is relatively unimpressive at 4W/core for an A57 (this power includes memory controllers, I/O, etc.), probably due to the older process technology and the standard ARM core," he said.

A 25W version of the A1100 uses four cores at 1.7GHz with 2MBytes L2 cache. (Image: AMD)

The A1100 will find sockets in networking and storage appliances as well as Web servers, said Scott Aylor, corporate VP of AMD's enterprise group.

U.K.-based SoftIron will use it in software-defined storage systems. Caswell, a unit of Foxconn, will make appliances for Network Functions Virtualisation, targeting telecom carriers. And Silver Lining Solutions will develop a hosting service with systems using the chip.

"It took AMD a very long time to go from sampling to production, which strongly suggests that there wasn't huge customer demand," said Kanter.

It's not the first disappointment for the ARM server initiative expected to take several years to gain significant traction. Startup Calxeda folded after its 32bit SoCs failed to gain traction. And AMD canceled Skybridge, a plan for x86 and ARM-based chips that used a common socket and interface.

Hewlett-Packard has shown blade servers using ARM-based processors, but most of the current chips are also being sold into storage or embedded systems. Red Hat is shipping a development preview of Linux for ARM servers, but said before it can be commercially released it needs to test it on standard ARM servers, something not yet generally available.

Gigabyte, Hyve and Stack Velocity are shipping ARM-based systems or have plans to, and hundreds of open source cloud applications are running on ARMv8-A today, said Lakshmi Mandyam, director of server systems and ecosystems at ARM. Ongoing work from Linaro, Canonical, SuSE and Red Hat continue to strengthen the developer ecosystem for ARM servers and the Linaro 96boards programme will provide low cost development boards for ARM 64bit development, she added.

"There's a lot of heavy lifting in building an enterprise machine and a mature software ecosystem that can enable it," said Aylor.

AMD expects to deliver by the end of the year its first processors based on its next-generation x86 core called Zen. It also is developing a custom ARM server core, the K-12, but the company is not saying when it will ship processors using it. Presently, the K-12 is the next thing after the A1100 on AMD's ARM server road map.

"Overall, I still believe that AMD's future in the server market will be brightest as a vendor of x86 processors," noted Kanter.

"The x86 ecosystem is much larger, more developed, and more valuable in the data centre," Kanter said. "As an x86 processor vendor they are the only viable alternative to Intel and can run both Windows and Linux. As an ARM processor vendor, they are merely one of half a dozen alternatives that can run Linux," he added.

- Rick Merritt
  EE Times