Startup SeaMicro packs 512 Intel Atoms in server

How it works
The SeaMicro design was the brainchild of Gary Lauterbach. He designed MicroSparc 3 and 4 server processors at Sun Microsystems, worked on a supercomputer R&D project at Sun and designed the architecture for the upcoming high-end Bulldozer core at Advanced Micro Devices.

The heart of the SM1000 is an ASIC that links the Atom chips on a multi-dimensional torus interconnect with a total aggregate bandwidth of 1.28 Terabits/s. The chip also also emulates to a Linux operating system motherboard components such as storage and network controllers.

The 130nm ASIC links to Atom chip sets over PCI Express, handling standard Linux commands. Given its high level of abstraction, the ASIC could be used with other processors in the future.

"The trick is to present to the CPU and operating system all the devices it expects," said Feldman. "Then there are no special drivers required," he said.

The SeaMicro server uses three sets of adapter cards. A 5x12 inch computer card packs eight Z530 single-core Atom chips and their associated support chips. It also includes an ASIC and 2 Gbytes DDR2 DRAM for each CPU.

Critics have said the relatively small memory subsystems of Atom and ARM processors would make them inadequate for running the memory-intensive MapReduce and Hadoop algorithms that are strategic for big Web sites such as Google and Yahoo. But Feldman disagreed.

"We have six customers currently doing MapReduce," he said.

A second card in the SeaMicro systems is a disk controller. It uses two Xilinx Virtex 5 FPGAs to link to the ASICs and eight serial ATA hard disk or solid-state drives. A networking card uses similar FPGAs and supports eight Gbit or two 10G Ethernet ports.

SeaMicro also implemented in-line load balancing as part of its network design. The feature saves additional power and space by eliminating the need for a separate load balancing system typically used with today's servers.

The load balancing feature supports existing server management software packages.

"We had leading data center companies come and show us their management tools so we could make sure we can manage their systems," said Feldman. "Mostly they use their own scripts for features such as pooling computer nodes and setting utilization thresholds," he said.

A fully configured SM1000 can pack 64 SATA drives and 64 Gbit Ethernet links or 16 10G links. A base system costs $139,000 and consumes less than 2 kilowatts.

The company has raised $25 million in venture financing from investors including Khosla Ventures and Draper Fischer Jurvetson. It also won a Department of Energy grant for $9.3 million to help develop its system.

The company is not currently seeking more financing. All 52 of its employees are based in Silicon Valley.

"We believe in hiring extraordinary people and sitting them next to each other," said Feldman.