Performance of Gaussian Approximation Potentials

Even for small systems, GAP potentials in our current implementation are order of magnitudes faster than Density Functional Theory, but significantly—about a hundred times— more expensive than analytical potentials. Calculation of the energies and forces requires about 0.01 s for every atom on a single CPU core. For comparison, a timestep of a 216-atom simulation cell takes about 190 s per atom on a single core by CASTEP, which corresponds to 20,000-fold speedup. The same calculation for iron would take a million times longer by CASTEP. 

Warren, R.G. Wenzel, J.L. Yamell, Inelastic Scattering of Neutrons, (International Atomic Energy Agency, Vienna, 1965), p. 361 

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