[petsc-users] KSP linear solver returns inf

[Manav Bhatia]

Hi, 

  I am using the KSP linear solver for my system of equations, without any command line options at this point. I have checked that the L1 norms of my system matrix and the force vector are finite values, but the KSP solver is returning with an “inf” residual in the very first iteration. 

  The problem has 6.7M dofs and I have tried this on multiple machines with different number of nodes with the same result. 

   Is there a reason why the solver would return after the first iteration with an inf? 
 
   I am not sure on where to start debugging this case, so I would appreciate any pointers. 

Thanks,
Manav