[petsc-users] Number of nonzeros > 2^31-1

[Nicolas TARDIEU]

Dear PETSc users,

I am solving an unstructured finite element-based problem with 500 
millions unkwowns with PETSc.
The number of nonzeros is greater than 2^31-1. 
Here is the KSPView I get : 
----------------------------------------------------------------------------------------------------------------
  Matrix Object:   700 MPI processes 
    type: mpiaij
    rows=499125000, cols=499125000
    total: nonzeros=-2147483648, allocated nonzeros=-2147483648
    total number of mallocs used during MatSetValues calls =0
      using I-node (on process 0) routines: found 242923 nodes, limit used 
is 5
----------------------------------------------------------------------------------------------------------------

As you can see, The number of nonzeros is <0.
I would like to check that this is due to the number of nonzeros being 
greater than 2^31-1.

Here is a short description of the size of differents types : 
----------------------------------------------------------------------------------------------------------------
Compiled with full precision matrices (default)
sizeof(short) 2 sizeof(int) 4 sizeof(long) 8 sizeof(void*) 8 
sizeof(PetscScalar) 8
----------------------------------------------------------------------------------------------------------------

Is there a workaround? Should I worry about the result of my simulation?

Thanks in advance,
Nicolas
  
 
Nicolas TARDIEU
Ing. Chercheur
EDF - R&D Dpt AMA
 
nicolas.tardieu at edf.fr
Tél. : 01 47 65 39 05
  
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