amgcl

test.log

```
Solver
======
Type:             FGMRES(30)
Unknowns:         4898600
Memory footprint: 2.26 G

Preconditioner
==============
Schur complement (two-stage preconditioner)
  Unknowns: 4898600(1025810)
  Nonzeros: 306280272
  Memory:  9.52 G

[ U ]
Solver
======
Type:             CG
Unknowns:         645465
Memory footprint: 59.09 M

Preconditioner
==============
Number of levels:    5
Operator complexity: 1.23
Grid complexity:     1.16
Memory footprint:    2.18 G

level     unknowns       nonzeros      memory
---------------------------------------------
    0       645465        4338381      1.76 G (80.99%)
    1        80853         795669    342.46 M (14.85%)
    2        15180         189672     79.54 M ( 3.54%)
    3         3876          32526     12.54 M ( 0.61%)
    4          216            366     63.29 K ( 0.01%)


[ P ]
Solver
======
Type:             CG
Unknowns:         1025810
Memory footprint: 31.31 M

Preconditioner
==============
Relaxation as preconditioner
  Unknowns: 1025810
  Nonzeros: 10140614
  Memory:   170.39 M


U1 (11, 0.0054667)
P1 (9, 0.099764)
U2 (8, 0.00791351)
U1 (61, 0.00997342)
P1 (24, 0.0987746)
U2 (10, 0.0095329)
U1 (100, 0.0488727)
P1 (26, 0.0979894)
U2 (18, 0.00785953)
U1 (100, 0.160342)
P1 (24, 0.0966063)
U2 (100, 0.237679)
U1 (100, 0.229263)
....
```