The Department of Energy's Oak Ridge National Labs today powered up Titan, a new supercomputer with 299,008 CPU cores, 18,688 GPUs, and more than 700 terabytes of memory. Titan is capable of a peak speed of 27 quadrillion calculations per second (petaflops)—ten times the processing power of its predecessor at Oak Ridge—and will likely unseat DOE's Sequoia supercomputer (an IBM BlueGene/Q system at Lawrence Livermore National Laboratory) as the fastest in the world.

Based on the Cray XK7 system, Titan consists of 18,688 computing nodes, each with an AMD Opteron 6274 processor and an NVIDIA Tesla K20 GPU accelerator. The NVIDIA GPUs provide most of the computing horsepower for simulations, with the Opteron cores managing them. True to its name, Titan is big—it takes up 4,352 square feet of floorspace in ORNL's National Center for Computational Sciences.

The combination of GPUs and CPUs dramatically reduces the electrical power consumption required to generate the computing power required. "Combining GPUs and CPUs in a single system requires less power than CPUs alone," said Jeff Nichols, ORNL's Associate Laboratory Director for computing and computational sciences. In his written statement on the launch, he called Titan a "responsible move toward lowering our carbon footprint."

Titan is an upgrade to Jaguar, a Cray XK6 system which as of June was the sixth fastest supercomputer in the world, drawing seven megawatts at its 2.3-petaflop peak performance. Titan will provide about 10 times that performance at nine megawatts. To achieve the same performance using solely Opteron CPUs, according to NVIDIA officials, Titan would have had to have been four times larger and would have consumed over 30 megawatts of power. The move to a hybrid CPU/GPU architecture is another step down the road toward "exascale" computing systems—with a goal of achieving 1,000 quadrillion (or 1 quintillion) computations per second.

ORNL researchers have been preparing for the shift to Titan's hybrid architecture for the past two years as the upgrade from Jaguar was planned, and several projects are already set to run on the new architecture. James Hack, Director of ORNL's National Center for Computational Sciences, said "Titan will allow scientists to simulate physical systems more realistically and in far greater detail. The improvements in simulation fidelity will accelerate progress in a wide range of research areas such as alternative energy and energy efficiency, the identification and development of novel and useful materials and the opportunity for more advanced climate projections."