[petsc-users] KSPSetUp hanging up with HYPRE preconditioner

[Ghosh, Swarnava]

Hello,

    I am using petsc 3.4.1 interfaced with hypre 2.9.0b
    
    I am using the following lines of code to solve a Poisson equation using KSPGMRES with HYPRE preconditioner.
    pOfdft->laplaceOpr is a sparse matrix in MATMPIBAIJ format.   

  KSPCreate(PETSC_COMM_WORLD,&pOfdft->ksp);  
  KSPSetType(pOfdft->ksp,KSPGMRES);
  KSPSetTolerances(pOfdft->ksp,KSPTOL,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT);
  KSPSetOperators(pOfdft->ksp,pOfdft->laplaceOpr,pOfdft->laplaceOpr,SAME_NONZERO_PATTERN);
  KSPGetPC(pOfdft->ksp,&pOfdft->pc);  
  PCSetType(pOfdft->pc,PCHYPRE);  
  PCHYPRESetType(pOfdft->pc,"boomeramg");
  KSPSetFromOptions(pOfdft->ksp);  
  KSPSetUp(pOfdft->ksp);   
       
    The code runs fine when the size of matrix is small (4096 X 4096). 
    BUT the code remains stuck in KSPSetUp function when the size of matrix is bigger (262144 x262144) on 64 cores 120 gb ram.

   Could you please let me know the probable reason the why the code is hanging in KSPSetUp.
   If possible could you please share some C examples where you use a HYPRE preconditioner for solving a large system

Thanks,
Swarnava


-- 
Swarnava Ghosh
PhD Candidate,
Structural Engineering, Mechanics and Materials
School of Civil and Environmental Engineering
Georgia Institute of Technology
Atlanta, GA 30332