High performance parallel processing project (HPPPP) advanced materials designs for massively parallel environment CRADA No. TC-0824-94-I
The main goal of this project was to provide U.S. industry with breakthrough capabilities in advanced atomistic materials simulation by using innovative new MPP algorithms, methods, and computers. Moreover, many computational tasks of central importance in materials modeling and simulation had wide applicability, and their optimization would benefit other industrial areas of research outside the confines of ab initio electronic structure calculations of materials. These include parallel input/output and parallel basic linear algebra subroutines for eigenvalue problems. LLNL completed the initial testing of ab initio material simulation (PCGPP) code in March 1996. The next months were spent optimizing the code interfaces for user-friendly use and tuning for better efficiency and performance. Early simulations indicated that a significant speedup with 89% parallel efficiency had been accomplished for processor number up to 64. Further implementations have been made throughout the course of the project. A parallel implementation of the PCGPP algorithm involves three principal components, namely a complex 3D FFT, input/output and basic linear algebra subroutines (BLAS) such as CAXPY. The parallel algorithm was first implemented using Cray Research Inc.'s Shared Memory Library (SHMEM) and with the MPI library in the latest version for general application in other Platforms such as IMB SP system. Our programming strategies contain four major elements: Automatic domain decomposition; parallel I/0 which can speed up the I/0 linearly with the number of processors; Distributed 3D complex fast Fourier transform (3D CFFT) routines. Another technical objective was the application of advanced ab initio electronic structure methods, at PARC and at LLNL, to specific physics problems of primary importance to research activities in the Electronic Materials Laboratory at Xerox PARC, including (but not limited to) investigations of the atomic and electronic structure of amorphous silicon and defect energetic in III-V semiconductor materials. Investigations of interface band alignment between crystalline and amorphous silicon, and the effect of supercell size on the formation energies of neutral and charged point defects in GaAs semiconductors, were performed and completed during the duration of this project.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE Office of Defense Programs (DP)
- DOE Contract Number:
- W-7405-Eng-48
- OSTI ID:
- 764030
- Report Number(s):
- UCRL-ID-140518/LLNL-TR-821380; IM #1032656 CRADA No. TC-0824-94-I
- Country of Publication:
- United States
- Language:
- English
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