from March 23, 2003, News-Sentinel

original URL:
http://www.knoxnews.com/kns/local_news/article/0,1406,KNS_347_1832471,00.html

By FRANK MUNGER, munger@knews.com
March 23, 2003

Cray X1 supercomputer tests impress officials

OAK RIDGE - The first cabinet of the heralded Cray X1 supercomputer has arrived at Oak Ridge National Laboratory, and lab officials are excited by early results.

Thomas Zacharia, ORNL's director of computing and computational sciences, said initial tests on a limited number of processors exceeded the calculating speed of any U.S. machine. And, in comparison runs with each using 16 processors, the Cray rivaled Japan's Earth Simulator - the world's fastest supercomputer - although the fully functional Japanese machine is capable of much greater speeds, he said.

"We do believe this is an indication that if we were to build a machine of a similar size, it would surpass the Earth Simulator,'' Zacharia said.

Officials emphasized, however, there's a long way to go before declaring success with Cray's new-generation architecture that features vector processing.

"This is like your baseball team winning the first five games of the year,'' said ORNL Director Bill Madia. "We're not in the World Series yet. It's just the first week of the year. But our team is doing really, really well.''

The "preliminary benchmarking'' was conducted at Cray's manufacturing facility before delivery to ORNL, and the test involved only 16 processors - one-fourth the capacity of a single cabinet. ORNL's Cray X1 supercomputer will have eight cabinets initially, each of them loaded to half-capacity (32 processors).

"We have the ability to fully populate them later,'' Zacharia said.

In the preliminary evaluation, the Cray processors ran a complex code for climate change developed at Los Alamos National Laboratory. The code is called Parallel Ocean Program.

According to Zacharia, the 16 processors of the Cray X1 were able to do 35.3 "simulation years'' per day. That exceeded the 24.8 simulation years accomplished with 256 processors on ORNL's IBM Power 4, heretofore the fastest U.S. run of the climate code, he said.

The Earth Simulator reportedly can do 30 simulation years of the climate code using 16 processors, which is a tiny fraction of its total capacity. The exact capabilities of the Japanese machine aren't clear, because U.S. experts have limited access to the supercomputer.

There are plenty of expansion plans for the Cray system in the months and years ahead, as ORNL and the computer company work together to develop the world's top machine for science research.

Zacharia said the maximum configuration involves 64 cabinets.

"This is a very complex machine,'' he said. "We have lots of challenges ahead, but I think we're well on our way.''

The Cray X1 has a closed-loop cooling system in which an inert liquid is sprayed directly onto the computer chips.

Zacharia said initial indications are that the Cray supercomputer may perform as its developers planned, which is encouraging news in a high-risk field that's fraught with uncertainty.

"Clearly you build a machine hoping it will perform a certain way. Am I surprised? I wouldn't say that. Am I very pleased? Yes, absolutely,'' Zacharia said.

Additional tests will be conducted over the next few weeks after the first components are assembled here, and the ORNL official said he believes the processors will perform just like they did at the Cray manufacturing facility. "I expect the results could even get better,'' he said.

Zacharia said the laboratory would not bring additional cabinets of the X1 system to Oak Ridge until a new computing facility is completed in May or June.

While pleased by the early test results, Zacharia said he is even more excited by the cooperative spirit in the U.S. scientific community. Other research labs have "rallied behind this effort'' and collaborated on test plans for the new supercomputer, he said.

"A lot has been said about Oak Ridge and the other labs having a friendly competition, and that's great,'' Zacharia said. "But what I'm really proud of is my colleagues at laboratories like Argonne and Lawrence Berkeley and universities have co-authored this evaluation plan.

"For this to be successful, we need the help of the broad scientific community.''

The Oak Ridge lab plans to use the Cray X1 for studies of climate change, fusion energy, biology, nanotechnology and other challenging areas of science research.

Zacharia said it's important to understand that the supercomputer, with its new architecture, is still in its earliest stages of development - unlike some mature IBM machines that have progressively improved over 10 years or more.

"This is encouraging,'' he said.

Senior writer Frank Munger may be reached at 865-342-6329.