[petsc-users] Using higher order ILU preconditioner

[Rachit Prasad]

Hi,

I am trying to solve a highly ill-conditioned matrix and am unable to get
convergence when using ILU(0) or Jacobi and SOR preconditioners. I tried to
implement a higher order ILU by increasing the level of fill-in to 1 by
calling

call PCFactorSetLevels(pc,1,ierr)

However, when I do that I get the following memory error:

[0]PETSC ERROR: --------------------- Error Message
------------------------------------
[0]PETSC ERROR: Out of memory. This could be due to allocating
[0]PETSC ERROR: too large an object or bleeding by not properly
[0]PETSC ERROR: destroying unneeded objects.
[0]PETSC ERROR: Memory allocated -2147483648 Memory used by process
-2147483648
[0]PETSC ERROR: Try running with -malloc_dump or -malloc_log for info.
[0]PETSC ERROR: Memory requested 18446744071863943168!

While I do understand that increasing the level of fill-in will require
higher memory, the memory requested seems to be way too high. Am I
implementing the higher order ILU correctly? Is there any other subroutine
which I need to call?

Regards,
Rachit
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