Takeshi Iwashita

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This paper covers the multi-threaded parallel processing of a sparse triangular solver for a linear system with a sparse coefficient matrix, focusing on its application to a parallel ICCG solver. We propose algebraic block multi-color ordering, which is an enhanced version of block multi-color ordering for general unstructured analysis. We present blocking(More)
In quasi-dynamic earthquake cycle simulations based on rate and state friction laws, we applied the method of HierarchicalMatrices (H-matrices) to multiplicative computations of the N N slip response function matrix and the slip deficit rate vector, where N is the number of divided cells on the plate surface. H-matrices, which are efficient low-rank(More)
A parallel ordering technique is a typical strategy for parallelization of the ICCG method. This paper proposes a new parallel ordering method to develop a parallel ICCG solver utilizing fewer synchronization points and achieving a high convergence rate. The new parallel ordering is called “block red-black ordering.” In this method, nodes in an analyzed(More)
We discuss a scheme for hierarchical matrices with adaptive cross approximation on symmetric multiprocessing clusters. We propose a set of parallel algorithms that are applicable to hierarchical matrices. The proposed algorithms are implemented using the flat-MPI and hybrid MPI+OpenMP programming models. The performance of these implementations is evaluated(More)
This paper introduces an automatic tuning method for the tiling parameters required in an implementation of the three-dimensional FDTD method based on time-space tiling. In this tuning process, an appropriate range for the tile size is first determined by trial experiments using cubic tiles. The tile shape is then optimized by using the Monte Carlo method.(More)
This paper proposes a new black-box-type parallel processing method for the incomplete Cholesky conjugate gradient (ICCG) solver. The new method is based on a multicolor ordering concept and an automatic reordering process in the solver. Parallel performance is evaluated in the context of three-dimensional finite edge-element eddy-current analysis. The(More)