1e7:
    serial  total 15.272s, compute 14.674s   1 core
  parallel  total  8.327s, compute  7.478s   2 cores
  parallel  total  4.726s, compute  3.912s   4 cores
  parallel  total  2.855s, compute  2.025s   8 cores
  parallel  total  1.911s, compute  1.085s  16 cores
  parallel  total  1.484s, compute  0.835s  32 cores

[
 [    686 8400511]
 [    668 8865705]
 [    665 6649279]
 [    663 9973919]
 [    621 6674175]
 [    616 7332399]
 [    616 7532665]
 [    613 5649499]
 [    611 8474249]
 [    608 6355687]
 [    606 8847225]
 [    606 9533531]
 [    603 6635419]
 [    601 9953129]
 [    598 7464846]
 [    598 7464847]
 [    597 3732423]
 [    595 5598635]
 [    593 8397953]
 [    590 6298465]
]

1e8:
  parallel  total 11.779s, compute  5.631s  32 cores