IBM describes Power7 supercomputer

PALO ALTO, Calif. -- IBM engineers sketched out plans at Hot Chips for a petaflops-class supercomputer built from as many as 64,000 Power7 processors. The design will bring a terabit/second of optical links to the system's main processor boards.

The computer is being built under a U.S. government program geared to create a new class of supercomputers that cost less, use less power yet are easier to program than today's systems. IBM expects to provide details at the Supercomputing 2010 conference in November in New Orleans about the expected performance and cost of its so-called PERCS (Productive, Easy-to-use, Reliable Computing System).

“This design represents a tremendous increase in the use of optics in systems, and a disruptive transition from datacom- to computer-style optical interconnect technologies,” said Baba Arimilli, an IBM chief architect working on chips for the system.

Arimilli and IBM senior design engineer Steve Baumgartner described at Hot Chips a bridge module that includes a hub chip and optical interconnects. The module is part of a board that includes four Power7 processors and forms a basic building block for the supercomputer which is made up of thousands of the boards in hundreds of chassis.

The 45nm hub chip measures 582mm2 and includes a 3.0 GHz internal 56x56 crossbar switch with integrated routing. The 61 x 95.5 mm module has 90 layers and contains connections for a total of 672 10Gbit/s optical transmitters or receivers.

The IBM engineers described their work and showed examples of the module in the video posted online. Cray is also building a petaflops supercomputer under the same program sponsored by the Defense Advanced Research Projects Agency.

It was just a year ago at Hot Chips that IBM first unveiled its Power7. At the time observers hailed the chip as one of the most scalable server processors to date.

The IBM hub module brings 48 10Gbit/s optical links to a Power7 board