Titan's novel architecture alone is no high-performance computing game-changer without applications capable of utilizing its innovative computing environment.
Titan's hardware is only as good as the research that exploits it. Preparing users is a greater challenge than past upgrades to Jaguar due to Titan's architectural evolution. This means researchers must rethink their problems in a way that might be new to their approach. In response, the OLCF has created the Center for Accelerated Application Readiness, or CAAR, a collaboration among application developers, Titan's manufacturer Cray, GPU manufacturer NVIDIA, and the OLCF's scientific computing experts.
CAAR has been working for nearly 2 years to establish best practices for code-writers. The center is divided into five teams working with five of the OLCF's most advanced and representative applications. Essentially these, and other potential applications, need to be able to keep the GPUs in Titan busy.
CAAR applications include the combustion code S3D; LSMS, which studies magnetic systems; LAMMPS, a bioenergy and molecular dynamics application; Denovo, which investigates nuclear reactors; and CAM-SE, a code that explores climate change.
All of these codes will benefit greatly when able to run at 20 petaflops. For instance, S3D will move beyond modeling simple fuels to tackle complex, larger-molecule hydrocarbon fuels such as isooctane (a surrogate for gasoline) and biofuels such as ethanol and butanol, helping America to achieve greater energy efficiency through improved internal combustion engines. And CAM-SE will be able to increase the simulation speed to between one and five years per computing day. This speed increase is needed to make ultra-high-resolution, full-chemistry simulations feasible over decades and centuries and will allow researchers to quantify uncertainties by running multiple simulations.
Please click here for information on the accelerated codes run on Titan [Microsoft Excel Document].
Science On Day 1
Illuminating the role of material disorder, statistics, and fluctuations in nanoscale materials and systems.
A molecular description of membrane fusion, one of the most common ways for molecules to enter or exit living cells.
Understanding turbulent combustion through direct numerical simulation with complex chemistry.
Answering questions about specific climate change adaptation and mitigation scenarios; realistically represent features like precipitation patterns / statistics and tropical storms.
Radiation transport – important in astrophysics, laser fusion, combustion, atmospheric dynamics, and medical imaging – computed on AMR grids.
Discrete ordinates radiation transport calculations that can be used in a variety of nuclear energy and technology applications.