Dell's new Copper servers pack up to 48 ARM system-on-chip processors into 3U of rack space, but they're not ready for a mainstream release just yet.
Dell has confirmed its plans to launch a family of servers based on the ARM instruction set architecture, starting with a limited roll-out for testing purposes.
The Dell Copper systems feature a 3U rack-mount chassis packed with up to 48 Marvell Armada system-on-chip processors based on ARMv7 with a 64-bit memory interface but a 32-bit local bus. The chips are mounted on sleds of up to four chips, with twelve sleds per system. Each SoC forms a self-contained server, with each sled featuring a dedicated gigabit Ethernet connection to a non-blocking L2 switch for inter-server communication.
While Dell's design is impressive, it's hardly the first: HP recently announced its own ARM server initiative under Project Moonshot, while microserver companies have been investigating ARM-based chips alongside Intel's low-power Atom range for many-core servers for years.
It's not until the introduction of 64-bit ARM IP - previously limited by design to 32-bit implementations - this year that the server market has sat up to take notice. While unable to compete on a raw speed level with chips from the likes of AMD and Intel, ARM server processors promise much for highly-parallel low-intensity tasks such as powering web-based applications with numerous simultaneous users.
Thanks to their low power draw and high efficiency, ARM-based servers promise much for data centre tasks where raw power isn't key. Growing power costs mean data centres bleed cash in the form of electricity bills and heating, ventilation and cooling (HVAC) costs. Chips that reduce the power draw and heat output are, therefore, of great interest in the industry.
For British chip design giant ARM, it's a major shift back to the early days of the company. Back when it was still known as Acorn RISC Machines, ARM's first chips were used in desktop and server computers including the BBC Micro (as an add-on secondary processor) and the Acorn Archimedes and RISC PC families.
The increasing popularity of the x86 instruction set followed by the explosion in low-cost PCs running Microsoft's MS-DOS and Windows operating systems put paid to the company's efforts in this direction, however. These days, ARM licences its low-power chip designs for use in tablets, smartphones and embedded systems - but hasn't exactly kept its desire to take US rival Intel on in the data centre and desktop markets a secret.
Dell's announcement of ARM-based servers is a major validation of the company's belief in its products as a solution in the data centre, but isn't quite a blanket approval: Dell is shipping limited quantities of the Copper systems to selected customers, including developers at Canonical and Cloudera who will work on a software infrastructure for the servers. General availability, then, is still some time away.