Oak Ridge's Jaguar supercomputer is a Cray XT distributed-memory massively parallel MIMD machine with 182 000 AMD quad-core Opteron processors running at 2.3 GHz and 362 terabytes of RAM
 

Petaflops Supercomputers

By Betsy Mason
Wired, November 2008

Edited by Andy Ross

In the Top 500 list of the world's fastest supercomputers, IBM holds the top spot, fending off a challenge from Cray. Both competitors broke petaflop speeds, performing just over 10¹⁵ floating-point calculations per second.

These computers will push simulation to the forefront of science. Scientists will be able to run new and vastly more accurate models of complex phenomena.

"The scientific method has changed for the first time since Galileo invented the telescope," said computer scientist Mark Seager of Lawrence Livermore National Laboratory.

Supercomputing has made huge advances over the last decade or so, gradually packing on the ability to handle more and more data points in increasingly complex ways. It has enabled scientists to test theories, design experiments, and predict outcomes as never before. The new class of petaflop-scale machines is poised to bring about major qualitative changes in the way science is done.

"The new capability allows you to do fundamentally new physics and tackle new problems," said Thomas Zacharia, who heads up computer science at Oak Ridge National Laboratory in Tennessee, home of the second-place Cray XT5 Jaguar supercomputer.

This new generation of petascale machines will move scientific simulation beyond just supporting the two main branches of science, theory and experimentation, and into the foreground. Instead of just hypotheses being tested with experiments and observations, large-scale extrapolation and prediction will become central to many scientific endeavors.

"It's getting to the point where simulation is actually the third branch of science," Seager said.

In the race to achieve this promise, Oak Ridge had made a push to top the speed list this year with its Cray XT5 Jaguar, but Los Alamos National Laboratory in New Mexico tweaked its IBM Roadrunner to keep the crown. Both more than doubled the performance of Livermore Lab's BlueGene/L IBM computer that led the pack a year ago.

The Jaguar was optimized for science. Oak Ridge surveyed scientists in many fields and built the computer to suit their needs. With 362 TB of memory, it has three times the memory capacity of any other computer.

The designers paid special attention to making the transition to Jaguar as easy as possible for scientists, allowing them to use applications they have already developed instead of spending years coding new ones to suit the computer.

Jaguar and its peers promise to take some scientific fields to the next level by enabling far more complex simulations. This in turn will inspire scientists to imagine new questions, which will in turn need even bigger supercomputers to answer.

Jaguar's power will be unleashed on scientific problems including drug discovery, photovoltaics, and new materials. Today's computer scientists can barely contain their excitement as they imagine what is now possible.
 

AR   About 15 years ago I was excited by teraflops machines. Now, three orders of magnitude later, we are only one order of magnitude short of the total processing power of the human brain, almost all of which is utterly wasted in the average brains of our fellow citizens, sad to say.