IBM supercomputer looms large

Each p655 Unix server is a four- or eight-processor module measuring seven inches high, 12 inches wide and 40 inches deep. When 16 of these modules are packed into a six-foot-tall rack designed for the servers, the collection weighs 3,600 pounds, said Jim McGaughan, director of IBM eServer product marketing.

"Apparently, if you really fill one of these racks, you have to put in special floor-tile reinforcements," said Illuminata analyst Gordon Haff. "It's certainly a heavyweight computer in more ways than one."

The system is geared to supercomputer customers, such as pharmaceutical companies or national laboratories, who need as much processing power in as little space as possible. To get similar supercomputer power before the introduction of the p655, IBM customers had been grouping 16-processor p670 servers or 32-processor p690 "Regatta" servers into clusters. However, those systems, with their higher capacity for data storage and networking bandwidth, are better adapted to general-purpose computing rather than supercomputing.

IBM is proud of the fact that it can squeeze 128 processors in a six-foot rack without causing overheating problems. "This is quite a feat of engineering, to be very candid," McGaughan said. Overheating, which can cause processing errors, is a universal problem in computer design, but is particularly important for high-density systems such as the p655.

A full cabinet with 16 of the p655 Unix servers, each with 4GB of memory and 218GB of hard-drive capacity, costs $2.1 million, McGaughan said. Customers who buy the p655 are more likely to gravitate toward systems with more memory, though; and when a system comes loaded with 16GB of memory, the list price goes up to about $2.6 million.

At the less-expensive end of the spectrum, a single four-processor machine with 4GB of memory and 218GB of hard drive capacity costs about $70,000, he said.

Supercomputer frenzy
The supercomputing industry has entered a frenzy of activity in anticipation of the beginning of the SC2002 supercomputer show in Baltimore, scheduled for Nov. 18.

On Thursday, Cray announced its new X1. In addition, SGI improved its top-end systems with the release of the Origin 3900 on Monday. Earlier, AMD--known mostly for building processors popular with consumers--announced it is building a system at Sandia National Laboratories.

For its part, IBM is steadily gaining ground in the market for supercomputers, with major customers in the defense industry, in corporate research and in academia. However, Hewlett-Packard is also making a strong showing, both with its high-end systems based on technology it acquired from Compaq Computer and with numerous lower-end systems. HP is also exerting pressure on its supercomputer rivals with systems based on Intel's Itanium processor, which HP helped to design.

"Itanium 2 hasn't made a big splash in general, but if you had to pick one area where it has gained some traction, it's in high-performance computing," Illuminata's Haff said.

Though IBM also is embracing Itanium, much of its energy is devoted to its own Power4 chip. IBM packs four Power4 processors into a dense chunk of ceramic and wires called a multichip module, a technology taken from its mainframe line. Each Power4 chip actually has two processors, making it a "dual-core" chip.

However, to build four-processor systems out of multichip modules that actually have eight processors, IBM disables one of the processors in each pair. Disabling half the chips might sound like a waste of silicon, but the technique has advantages in some circumstances because a single processor can exploit the double-strength infrastructure, such as communications lines and high-speed cache memory.

IBM's new p655 systems can be joined with the company's high-speed SP Switch 2, a technique that makes it easier to spread supercomputing calculations across a cluster of computers. McGaughan said IBM expects roughly half of its p655 customers will use the high-speed switch, with the remaining clients linking their systems with the slower and more pedestrian Ethernet networks.