Titan Cray XK7 supercomputer: Oak Ridge National Laboratory has world's fastest computer

OAK RIDGE — For at least the fourth time in history, Oak Ridge National Laboratory has the world's fastest computer on its campus.

The latest to ascend to the pinnacle is ORNL's Titan, the Cray XK7 supercomputer, which is No. 1 on the new Top500 list released today at the Supercomputing Conference being held in Salt Lake City, Utah. The new list was embargoed until 9 a.m. Eastern Standard Time by the team that does the twice-a-year rankings of the world's 500 fastest computers.

Titan, which features a new hybrid architecture, achieved a sustained computing capability of 17.5 petaflops — or 17.5 million billion mathematical calculations per second — on the Linpack benchmark tests to qualify for the list. The Cray machine reportedly has a peak capability of more than 27 petaflops.

Jeff Nichols, ORNL's scientific computing chief, said the lab team did not have time to fully optimize Titan in time for the benchmark tests.

"So, we have room for future performance increases," Nichols said by email.

The new Cray machine was assembled in the 200 cabinets occupied by its precedessor, Jaguar, another Cray machine at that one time (2009-2010) was the world's fastest supercomputer hailed for its high productivity in climate modeling and many other areas of science research. Other ORNL computers previously acknowledged as tops were No. 1 were the Intel Paragon (1995) and ORACLE (1953).

With the new results, Titan supplants Sequoia — an IBM Blue Gene/Q system at Lawrence Livermore National Laboratory in California — as No. 1. Sequoia is now the second-fastest supercomputer with a sustained capability of 16.3 petaflops, followed by the K computer, a Fujitsu system in Japan; Mira, an IBM system at Argonne National Laboratory in Illinois; and JUQUEEN, an upgraded IBM system in Germany that's now the fastest machine in Europe.

ORNL was scheduled to hold a press briefing today to discuss Titan's results and show off the new $100 million machine.

Another U.S. machine to debut on the the Top500 list was Stampede, a Dell supercomputer at the University of Texas, which was ranked No. 7.

ORNL recently announced that Titan had been fully loaded with a combination of a combination of central and graphics processing units, including NVDIA's new Tesla GPUs, while undergoing additional tweaks and acceptance testing.

There has been tremendous interest in Titan in high-performance computing circles because of its use of graphics processing units, which grew out of advanced technologies developed for video games, to greatly accelerate the computing power.

The 18,688 NVIDIA GPUs were paired with an equal number of 16-core AMD Opteron CPUs, combining to create far greater capabilities within the same footprint as Jaguar and, according to ORNL, requiring only slightly more electricity.

"Because they handle hundreds of calculations simultaneously, GPUs can go through many more than CPUs in a given time," ORNL said in an earlier statement. "By relying on its 299,008 CPU cores to guide simulations and allowing its new NVIDIA GPUs to do the heavy lifting, Titan will enable researchers to run scientific calculations with greater speed and accuracy."

The lab said Titan will be used for research on energy sources, climate change, efficient engines, materials and other scientific challenges.