The problem of parallel thread mapping is studied for the case of discrete orthogonal @math -simplices. The possibility of a @math time recursive block-space map @math is analyzed from the point of view of parallel space efficiency and potential performance improvement. The @math -simplex and @math -simplex are analyzed as special cases, where constant time maps are found, providing a potential improvement of up to @math and @math more efficient than a bounding-box approach, respectively. For the general case it is shown that finding an efficient recursive parallel space for an @math -simplex depends of the choice of two parameters, for which some insights are provided which can lead to a volume that matches the @math -simplex for @math , making parallel space approximately @math times more efficient than a bounding-box.
@cite_2: Dense matrix inversion is a basic procedure in many linear algebra algorithms. A computationally arduous step in most dense matrix inversion methods is the inversion of triangular matrices as produced by factorization methods such as LU decomposition. In this paper, we demonstrate how triangular matrix inversion (TMI) can be accelerated considerably by using commercial Graphics Processing Units (GPU) in a standard PC. Our implementation is based on a divide and conquer type recursive TMI algorithm, efficiently adapted to the GPU architecture. Our implementation obtains a speedup of 34x versus a CPU-based LAPACK reference routine, and runs at up to 54 gigaflops s on a GTX 280 in double precision. Limitations of the algorithm are discussed, and strategies to cope with them are introduced. In addition, we show how inversion of an L- and U-matrix can be performed concurrently on a GTX 295 based dual-GPU system at up to 90 gigaflops s.
Ries contributed with a parallel GPU method for the triangular matrix inversion @cite_2 . The authors identified that the parallel space indeed can be improved by using a (REC) of the grid, based on a strategy. The approach takes @math time by doing a balanced partition of the structure, from the orthogonal point to the diagonal.