$PDL::BIGPDL = 1;
PDL 2.021: perl test.pl 2e6  # 4.590 secs.
PDL 2.079: perl test.pl 2e6  # 7.252 secs.

# $PDL::BIGPDL = 1;  # line commented out
PDL 2.021: perl test.pl 2e6  # 4.490 secs.
PDL 2.079: perl test.pl 2e6  # 5.252 secs.