Phase diagram of supercomputers.

<p>The machine with the lowest execution time is shown for a given system size and number of cores. The colours used are the same as those shown in the top panel of Fig. 4. Boxes with dashed lines indicate that the data for one or more machines is not available; sparse dashed lines indicate that only one machine was run with these parameters. The inset shows the idealized diagram over the same range, using the timing estimates given by the fits of and .</p

Strong scaling on SuperMUC for four different system sizes.

<p>The full black lines gives the ideal scaling relative to the smallest system size. The fit to Amdahl's law is shown by the dashed black line, and the corrsponding value is given above the plot.</p

Absolute timings on the six machines.

<p>Top panel: prefactor for the cubic scaling with system size of the execution time in serial for the self-consistent calculation of the liquid water system (13 SCF iterations). Bottom panel: two examples of the fitting of to absolute timing data, extrapolated for all number of cores to serial timings using Amdahl's law and a fitted analytical expression of the strong scaling performance as a function of system size.</p

Timing comparison on Curie for two different SIESTA basis sets.

<p>Each data point plots the execution time of a particular system size simulated with the basis (23 NAOs/HO molecule) against that of a <i>different</i> system size simulated with the basis (46 NAOs/HO molecule), chosen so that the two systems have the same total number of basis orbitals. The two system sizes are shown in brackets (/); in each case, both simulations are performed on the same number of cores, equal to the number of molecules in the system.</p

Specifications for the six PRACE Tier-0 systems.

<p>We note that some systems include secondary types of nodes with different specifications; these are not listed here, and are not used for our tests.</p

Three types of scaling that can be investigated by systematically varying the number of molecules per core and the number of cores.

<p>The shaded cells show the suggested set of tests to perform on a typical HPC system.</p

The ELSI Infrastructure for Scalable Electronic Structure Theory

Lightning talk accompanying the poster describing the ELSI infrastructure in detail.<br