Grid 0 size 2 by 2 by 2
Grid 1 size 3 by 3 by 3
Grid 2 size 5 by 5 by 5
  0 KSP Residual norm 19.7337
  1 KSP Residual norm 0.301094
  2 KSP Residual norm 0.000434923
  3 KSP Residual norm 3.64335e-06
Residual norm 4.43813e-06 iterations = 3,
