Reference

function update!(p, J::SparseMatrixCSC)

Update the preconditioner p from the sparse Jacobian J in CSC format for the CPU

Note that this implements the same algorithm as for the GPU and becomes very slow on CPU with growing number of blocks.

BlockJacobiPreconditioner

Overlapping-Schwarz preconditioner.

Attributes

• nblocks::Int64: Number of partitions or blocks.
• blocksize::Int64: Size of each block.
• partitions::Vector{Vector{Int64}}:npart` partitions stored as lists
• cupartitions: partitions transfered to the GPU
• lpartitions::Vector{Int64}`: Length of each partitions.
• culpartitions::Vector{Int64}`: Length of each partitions, on the GPU.
• blocks: Dense blocks of the block-Jacobi
• cublocks: Js transfered to the GPU
• map: The partitions as a mapping to construct views
• cumap: cumap transferred to the GPU`
• part: Partitioning as output by Metis
• cupart: part transferred to the GPU

Applies in-place backward substitution with the U factor of F, under the assumptions:

1. U is stored transposed / row-wise
2. U has no lower-triangular elements stored
3. U has (nonzero) diagonal elements stored.

Applies in-place forward substitution with the L factor of F, under the assumptions:

1. L is stored column-wise (unlike U)
2. L has no upper triangular elements
3. L has no diagonal elements