Combined shared and distributed memory ab-initio computations of
molecular-hydrogen systems in the correlated state: process pool solution and
two-level parallelism
An efficient computational scheme devised for investigations of ground state
properties of the electronically correlated systems is presented. As an
example, (H2)n chain is considered with the long-range
electron-electron interactions taken into account. The implemented procedure
covers: (i) single-particle Wannier wave-function basis construction in the
correlated state, (ii) microscopic parameters calculation, and (iii) ground
state energy optimization. The optimization loop is based on highly effective
process-pool solution - specific root-workers approach. The hierarchical,
two-level parallelism was applied: both shared (by use of Open
Multi-Processing) and distributed (by use of Message Passing Interface) memory
models were utilized. We discuss in detail the feature that such approach
results in a substantial increase of the calculation speed reaching factor of
300 for the fully parallelized solution.Comment: 14 pages, 10 figures, 1 tabl