[thilinarmtb]

Dear Foamers,

I am new to OpenFOAM and have been playing with it for sometime. I am working on linear solvers and want to see
whether I can get a speedup after porting them to run on a GPU.

I read the following Forum posts and know how to get the matrix A from its ldu representation.

http://www.cfd-online.com/Forums/ope...ldumatrix.html

http://www.cfd-online.com/Forums/ope...fficients.html

http://www.cfd-online.com/Forums/ope...ddressing.html

http://www.cfd-online.com/Forums/ope...m-solvers.html

Is it correct to feed this recovered matrix and `source` to a separate linear system solver library for solving the system?

I am worried about the variables `interfaceBouCoeffs`, `interfaceIntCoeffs` and `interfaces` in `lduMatrix::solver` class.
What do they represent and How should I use them when recovering the original matrix from the ldu representation?

[alexeym]

Hi,

Maybe this is off topic, but did you check: Symscape's ofgpu[1] and their OpenFOAM 2.2.x patch[2]? They convert lduMatrix for solution on GPU.

I am worried about the variables `interfaceBouCoeffs`, `interfaceIntCoeffs` and `interfaces` in `lduMatrix::solver` class.
What do they represent and How should I use them when recovering the original matrix from the ldu representation?

Interface boundary coefficients, interface internal coefficients, and interfaces are relevant for parallel cases if I am not mistaken.

1. http://www.symscape.com/gpu-1-1-openfoam, http://www.symscape.com/files/articl...fgpu-1-1-0.tgz
2.http://www.symscape.com/openfoam-2-2-x-on-windows, http://www.symscape.com/files/articl...-2-x.patch.zip

[thilinarmtb]

Hi alexeym,

Thank you very much for the reply.

I checked those and also one of my friends pointed out that this can be done
by creating a LU Matrix out of the lduMatrix. See the following link:

https://github.com/OpenFOAM/OpenFOAM...GSolver.C#L265