life 1_000 generations jruby-1.7.22 real 0m15.749s user 0m27.559s sys 0m0.840s jruby-9.0.0.0 real 0m18.195s user 0m33.418s sys 0m0.977s rbx-2.5.8 real 0m28.032s user 0m35.972s sys 0m0.611s ruby-2.2.3 real 0m28.818s user 0m28.129s sys 0m0.535s