Harrod said the U.S. can't build a "stunt machine," or a one-off system that has limited usefulness. The exascale effort has to result in marketable technologies, he said.
"If I can do a 20MW exascale system in 500 cabinets that means we have a petaflop in a single cabinet -- that's amazing," said Harrod. Such a result would mean that a petascale system could be small enough to fit in the data closet of an academic department or business unit.
"We have to do a fair amount of research before we can actually start going out and designing and developing these computers," said Harrod. "We actually don't know exactly how to design and develop these computers at this point in time."
Funding for an exascale system remains a question. The U.S. has approved funds cover preliminary efforts, about $73 million, but has not yet allocated exascale program funding.
"We don't anticipate the ECI [exascale] funding to start before 2014," said Harrod.
FY 2014 begins Oct. 1, 2013. But current fiscal problems in Congress, the so-called fiscal cliff in particular, makes Harrod pessimistic about funding for next year. "To be honest, I would be somewhat doubtful of that at this point in time," he said.
"The biggest problem is the budget," said Harrod. "Until I have a budget, I really don't know what I'm doing," he said.
Patrick Thibodeau covers SaaS and enterprise applications, outsourcing, government IT policies, data centers and IT workforce issues for Computerworld. Follow Patrick on Twitter at @DCgov, or subscribe to Patrick's RSS feed . His e-mail address is email@example.com.
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