Benchmark: timing 1 iterations of normal, tail...
    normal: 123 wallclock secs ( 6.58 usr +  1.13 sys =  7.71 CPU) @  0.13/s (n=1)
            (warning: too few iterations for a reliable count)
      tail:  3 wallclock secs ( 3.50 usr +  0.01 sys =  3.51 CPU) @  0.28/s (n=1)
            (warning: too few iterations for a reliable count)