[SC08] SGI Designs Atom-based Supercomputer

Nov 21, 2008
Tetsuo Nozawa, Nikkei Electronics
A 3U-high package houses 90 blocks. "A few more blocks can be added because the actual package is slightly deeper," SGI said.
A 3U-high package houses 90 blocks. "A few more blocks can be added because the actual package is slightly deeper," SGI said.
[Click to enlarge image]
The substrate mounted with the Atom N330 and the block composed of two such substrates. The substrate is mounted with actual chips, but the block is a mockup.
The substrate mounted with the Atom N330 and the block composed of two such substrates. The substrate is mounted with actual chips, but the block is a mockup.
[Click to enlarge image]
A close-up picture of the substrate. The slender chip on the left is the Atom N330. The big chip in the center is a controller IC. The four chips on the front side are memory chips.
A close-up picture of the substrate. The slender chip on the left is the Atom N330. The big chip in the center is a controller IC. The four chips on the front side are memory chips.
[Click to enlarge image]

Silicon Graphics Inc (SGI) of the US exhibited a concept model of a novel high performance computer (HPC) at Super Computing 2008 (SC08), an international convention and exhibition on HPCs.

The computer is being developed under the code name of "Project Molecule." The aim of the project is to "create a supercomputer featuring ultrahigh-density, low power consumption and low cost using the ultimate commodity processor that can be easily programmed," SGI said.

The commodity processor used in this concept model is the "Atom N330," which Intel Corp developed for mobile devices called "MID (Mobile Internet Device)."

SGI exhibited a chassis, which corresponds to a 15cm-high (3U) rack. And, in the chassis, 90 blocks that look like building blocks are laid out with little space left. The block has several square pores dimensioned about 5 x 5mm so that air from the air-cooling fan on the back of the package can pass through the pores.

The block consists of two 5 x 5mm substrates attached to each side of a pore structure used for air cooling by resin. Each of the substrates is mounted with microprocessors, LSIs for datapath control, and eight memory chips on two sides. The dual-core Atom is incorporated as a microprocessor. This atom is a 1.3GHz model and supports "x86-64" instruction set. Each substrate has a memory capacity of 2 Gbytes.

In order to achieve ultrahigh density, more than 180 microprocessors with CPU cores exceeding 360 are packed into the 3U rack. The power consumption of this Atom is as low as 10W, making it possible to array many blocks leaving small spaces for tiny air-cooling pores. The power consumption of the whole package is less than 2kW, according SGI.

"As the next step, we are planning to employ a liquid-cooling system and further improve the density by, for example, packing more than 10,000 CPU cores in one rack," the company said.

The Atom is a low power consumption microprocessor developed by Intel for use in MIDs. Intel explains that it is not suitable for complicated processing and only good for Web browsing and checking e-mail.

In respect to this point, SGI said, "We place priority on memory bandwidth, and the Atom's memory bandwidth is not small. A supercomputer based on this model will be intended exclusively for calculation, in which memory bandwidth is important."

IBM Corp's "Blue Gene" supercomputer was developed under a similar concept. The Blue Gene uses the "PowerPC 440" embedded microprocessor. SGI admits that there are some similarities between its concept model and the Blue Gene, but said "they are not the same." The biggest difference is in that the Atom microprocessor supports the x86-64 instruction set, which is designed for general PCs and servers.

In respect to its commercialization, "It has yet to be given the go-ahead. But once its commercialization has been decided, we will be able to develop a product in 15 to 18 months," SGI said.