Partially overshadowed by the dislocations of Hurricane Sandy was Oak Ridge National Laboratory’s unveiling of its Titan supercomputer, a 20-petaflop Cray XK7 that will crunch massive numbers to run simulations in materials science, combustion, and, appropriately, climate change. (In the shadow of the storm, it’s interesting to note how many of Titan’s non-weather applications also have environmental implications.)
The system contains 18,688 nodes, each containing a 16-core AMD Opteron 6274 CPU and an NVIDIA Tesla K20 graphics processing unit. The design is 10 times as powerful as ORNL’s previous supercomputer, the Jaguar, but it fits into the same space and uses only a little more power.
“Combining GPUs and CPUS in a single system requires less power than CPUs alone, and is a responsible move towards lowering our carbon footprint,” said ORNL associate director Jeff Nichols in the debut announcement. Titan’s 299,008 CPUs will guide the complex simulations, while the even faster multi-core GPUs will handle the details.
It will take a while before Titan finishes acceptance testing. When it goes online, its biggest client will be the Department of Energy’s INCITE (Innovative and Novel Computational Impact on Theory and Experiment) program.
The biggest-iron to-do list includes:
- Calculating nanoscale magnetic properties and temperature sensitivities of steels, nickel-iron alloys, and advanced permanent magnets using Wang-Landau locally self-consistent multiple scattering (WL-LSMS) methods.
- Modeling combustion in the turbulent environment of an internal combustion engine—potentially important to improving engine designs that will both conserve fossil fuel resources and reduce greenhouse gas production.
- Modeling the behavior of neutrons in a nuclear power reactor—part of a study intended to help extend the working lives of aging reactors that still provide about 20% of America’s power. (ORNL says Titan will be able to simulate one fuel-rod service cycle in 13 hours, less than a quarter of the time Jaguar needed.)
- Simulating the long-term evolution of the world’s climate, helping to anticipate future air quality and the behavior of suspended particles. The simulation will reduce the world to an array of 14x14 km cells, “imagining” five years of real time per day of computing time. (Jaguar could simulate just three months in a day of calculation.)