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Incomplete Cholesky in Parallel

+1 vote

Hi there,

I'd like to know if there exist a implementation of a Imconplete Choesky preconditioner that run in parallel processing.

The use of the 'icc' krylov option in serial work perfectly, but in parallel, i get the following error message:

*** Error: Unable to successfully call PETSc function 'KSPSolve'.
*** Reason: PETSc error code is: 56.
*** Where: This error was encountered inside /build/dolfin-k_QrtL/dolfin-1.6.0/dolfin/la/PETScKrylovSolver.cpp.
*** Process: 5
*** DOLFIN version: 1.6.0

and a copy of that for each processor.

Thanks in advice for any answer!

asked Feb 7, 2016 by felipe_galarce FEniCS User (1,190 points)

Hi, PETSc documentation on ICC states that the factorization is not implemented in parallel, see here. As the operation is not supported you get error with code 56. I don't think any of the linear algebra backends that DOLFIN uses has support for this.

commented Feb 8, 2016 by MiroK FEniCS Expert (80,920 points)

Ok, thanks anyway!

commented Feb 8, 2016 by felipe_galarce FEniCS User (1,190 points)

1 Answer

0 votes

DOLFIN doesn't provide preconditioners, makes them available via the linear algebra backends. PETSc can use the parallel ILU from Hypre. Hypre may also have ICC.

answered Feb 23, 2016 by Garth N. Wells FEniCS Expert (35,930 points)
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