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 19.2986
  1 KSP Residual norm 0.0218844
  2 KSP Residual norm 1.98484e-06
Residual norm 2.46757e-06 iterations = 2,