Apple adds HPC customer but falls from Top500

Company to build a $5.8 million 1,566-node supercomputer for the U.S. Army

Apple Computer Inc. took a step forward and a step backward Monday in its quest to prove itself a viable player in the world of high performance computing (HPC).

The Cupertino, California, computer vendor announced a deal with U.S. Army contractor Colsa Corp. to build a 1,566-node supercomputer that is expected to be capable of as many as 25 trillion mathematical operations per second, according to Colsa.

Called MACH 5 (Multiple Advanced Computers for Hypersonic research), the $5.8 million system is designed to do aero-thermodynamic modeling for the Army's Missile Research, Development and Engineering Center. It is expected to be operational by November and, if it were benchmarked today, would rank just behind the Japan Marine Science and Technology Center's $350 million Earth Simulator, Colsa said.

At the same time, an Apple-based supercomputer at the Virginia Polytechnic Institute and State University, which has 1,100 nodes and rocketed to third place last November in the semi-annual Top500 list of the world's fastest supercomputers, failed to appear on a revised version of the list that was published Monday, leaving Apple unrepresented on the Top500.

Virginia Tech, which was Apple's first entry into the top echelons of the world's supercomputers, was unable to submit a benchmark because it is in the process of building a new supercomputer, based on Apple's latest rack-mounted server, the Xserve G5, according to Alex Grossman, director of server and storage hardware at Apple.

Virginia Tech announced plans to migrate its supercomputer to the Xserve G5 in January, just months after it was built. The university has subsequently dismantled its original system, which was based on the desktop Power Mac G5 system, Grossman said.

The Xserve G5 met with some shipping delays earlier this year, but the dual processor systems that Virginia Tech plans to use have been shipping in volume since April, Grossman said.

"We have a lot more customers to come that will be on the Top500 list, we believe," Grossman said.

One such customer will be Colsa, which expects to run the Top500's Linpack benchmark on the MACH 5 in time for the November list, according to Antony DiRienzo, executive vice president at Colsa. Colsa will take its first truckload of 300 dual-processor Xserve G5 systems next week, DiRienzo said.

The Virginia Tech system has attracted considerable media attention, but some supercomputer users say that Apple has yet to prove that its computers can do more in high performance computing than run benchmarks.

"All I've seen are Linpack benchmarks, and that's not why we buy computers," said Scott Studham, manager of computer operations with the Pacific Northwest National Laboratory's Molecular Science Computing Facility. "The science impacts of these systems still haven't been demonstrated, and the fact that they disappeared from the most recent Top500 list tells me that the first system didn’t work or it was put together solely for Linpacking, which isn't a useful measure of a supercomputer," he said.

Though the Xserve G5 shows a lot of promise, the fact that the Virginia Tech system has been down for several months raises questions about Apple's ability to migrate customers to new HPC systems, said Jeff Nichols, a director with the computer science and math division at Oak Ridge National Laboratory. "They really made a mistake by not having the machine there throughout the procurement of the follow-up system," he said. "When a machine disappears for three or four months, then that's a bad thing."

Colsa, however, is convinced that the Xserve G5 will be appropriate for its thermodynamic modeling application. The company also evaluated systems based on Advanced Micro Devices Inc.'s and Intel Corp.'s processors, but "the G5 came across as running our code better," DiRienzo said.

Apple will have at least a "small number" of systems on November's list, predicted Erich Strohmaier, one of the computer scientists who maintains the Top500 list. "There's still a lot of interest in the community," he said. "A lot of people are ready to order (Xserve G5's) if they could get them delivered," he said.