Dear all,

the simulation runs with

```
<linear_solver>
<name>general_linear_solver</name>
<petsc>
<prefix>hc</prefix>
<parameters>-hc_mat_type aij -hc_pc_type lu -hc_pc_factor_mat_solver_type mumps -hc_ksp_view</parameters>
</petsc>
</linear_solver>
```

This seems to be the simplest parameter combination.

Output example:

```
KSP Object: (hc_) 1 MPI processes
type: gmres
restart=30, using Classical (unmodified) Gram-Schmidt Orthogonalization with no iterative refinement
happy breakdown tolerance 1e-30
maximum iterations=10000, nonzero initial guess
tolerances: relative=1e-05, absolute=1e-50, divergence=10000.
left preconditioning
using PRECONDITIONED norm type for convergence test
PC Object: (hc_) 1 MPI processes
type: lu
out-of-place factorization
tolerance for zero pivot 2.22045e-14
matrix ordering: nd
factor fill ratio given 0., needed 0.
Factored matrix follows:
Mat Object: 1 MPI processes
type: mumps
rows=26874, cols=26874
package used to perform factorization: mumps
total: nonzeros=5792610, allocated nonzeros=5792610
MUMPS run parameters:
SYM (matrix type): 0
PAR (host participation): 1
ICNTL(1) (output for error): 6
ICNTL(2) (output of diagnostic msg): 0
ICNTL(3) (output for global info): 0
ICNTL(4) (level of printing): 0
ICNTL(5) (input mat struct): 0
ICNTL(6) (matrix prescaling): 7
ICNTL(7) (sequential matrix ordering):7
ICNTL(8) (scaling strategy): 77
ICNTL(10) (max num of refinements): 0
ICNTL(11) (error analysis): 0
ICNTL(12) (efficiency control): 1
ICNTL(13) (sequential factorization of the root node): 0
ICNTL(14) (percentage of estimated workspace increase): 20
ICNTL(18) (input mat struct): 0
ICNTL(19) (Schur complement info): 0
ICNTL(20) (RHS sparse pattern): 0
ICNTL(21) (solution struct): 0
ICNTL(22) (in-core/out-of-core facility): 0
ICNTL(23) (max size of memory can be allocated locally):0
ICNTL(24) (detection of null pivot rows): 0
ICNTL(25) (computation of a null space basis): 0
ICNTL(26) (Schur options for RHS or solution): 0
ICNTL(27) (blocking size for multiple RHS): -32
ICNTL(28) (use parallel or sequential ordering): 1
ICNTL(29) (parallel ordering): 0
ICNTL(30) (user-specified set of entries in inv(A)): 0
ICNTL(31) (factors is discarded in the solve phase): 0
ICNTL(33) (compute determinant): 0
ICNTL(35) (activate BLR based factorization): 0
ICNTL(36) (choice of BLR factorization variant): 0
ICNTL(38) (estimated compression rate of LU factors): 333
CNTL(1) (relative pivoting threshold): 0.01
CNTL(2) (stopping criterion of refinement): 1.49012e-08
CNTL(3) (absolute pivoting threshold): 0.
CNTL(4) (value of static pivoting): -1.
CNTL(5) (fixation for null pivots): 0.
CNTL(7) (dropping parameter for BLR): 0.
RINFO(1) (local estimated flops for the elimination after analysis):
[0] 8.52752e+08
RINFO(2) (local estimated flops for the assembly after factorization):
[0] 7.85459e+06
RINFO(3) (local estimated flops for the elimination after factorization):
[0] 8.52752e+08
INFO(15) (estimated size of (in MB) MUMPS internal data for running numerical factorization):
[0] 72
INFO(16) (size of (in MB) MUMPS internal data used during numerical factorization):
[0] 72
INFO(23) (num of pivots eliminated on this processor after factorization):
[0] 26874
RINFOG(1) (global estimated flops for the elimination after analysis): 8.52752e+08
RINFOG(2) (global estimated flops for the assembly after factorization): 7.85459e+06
RINFOG(3) (global estimated flops for the elimination after factorization): 8.52752e+08
(RINFOG(12) RINFOG(13))*2^INFOG(34) (determinant): (0.,0.)*(2^0)
INFOG(3) (estimated real workspace for factors on all processors after analysis): 5792610
INFOG(4) (estimated integer workspace for factors on all processors after analysis): 261736
INFOG(5) (estimated maximum front size in the complete tree): 399
INFOG(6) (number of nodes in the complete tree): 1394
INFOG(7) (ordering option effectively use after analysis): 5
INFOG(8) (structural symmetry in percent of the permuted matrix after analysis): 100
INFOG(9) (total real/complex workspace to store the matrix factors after factorization): 5792610
INFOG(10) (total integer space store the matrix factors after factorization): 261736
INFOG(11) (order of largest frontal matrix after factorization): 399
INFOG(12) (number of off-diagonal pivots): 0
INFOG(13) (number of delayed pivots after factorization): 0
INFOG(14) (number of memory compress after factorization): 0
INFOG(15) (number of steps of iterative refinement after solution): 0
INFOG(16) (estimated size (in MB) of all MUMPS internal data for factorization after analysis: value on the most memory consuming processor): 72
INFOG(17) (estimated size of all MUMPS internal data for factorization after analysis: sum over all processors): 72
INFOG(18) (size of all MUMPS internal data allocated during factorization: value on the most memory consuming processor): 72
INFOG(19) (size of all MUMPS internal data allocated during factorization: sum over all processors): 72
INFOG(20) (estimated number of entries in the factors): 5792610
INFOG(21) (size in MB of memory effectively used during factorization - value on the most memory consuming processor): 63
INFOG(22) (size in MB of memory effectively used during factorization - sum over all processors): 63
INFOG(23) (after analysis: value of ICNTL(6) effectively used): 0
INFOG(24) (after analysis: value of ICNTL(12) effectively used): 1
INFOG(25) (after factorization: number of pivots modified by static pivoting): 0
INFOG(28) (after factorization: number of null pivots encountered): 0
INFOG(29) (after factorization: effective number of entries in the factors (sum over all processors)): 5792610
INFOG(30, 31) (after solution: size in Mbytes of memory used during solution phase): 65, 65
INFOG(32) (after analysis: type of analysis done): 1
INFOG(33) (value used for ICNTL(8)): 7
INFOG(34) (exponent of the determinant if determinant is requested): 0
INFOG(35) (after factorization: number of entries taking into account BLR factor compression - sum over all processors): 5792610
INFOG(36) (after analysis: estimated size of all MUMPS internal data for running BLR in-core - value on the most memory consuming processor): 0
INFOG(37) (after analysis: estimated size of all MUMPS internal data for running BLR in-core - sum over all processors): 0
INFOG(38) (after analysis: estimated size of all MUMPS internal data for running BLR out-of-core - value on the most memory consuming processor): 0
INFOG(39) (after analysis: estimated size of all MUMPS internal data for running BLR out-of-core - sum over all processors): 0
linear system matrix = precond matrix:
Mat Object: 1 MPI processes
type: mpiaij
rows=26874, cols=26874
total: nonzeros=1054062, allocated nonzeros=1054062
total number of mallocs used during MatSetValues calls=0
using I-node (on process 0) routines: found 11493 nodes, limit used is 5
```

Best,

Tuanny