perl cmparray.pl
Benchmark: timing 5000 iterations of join, md5...
      join: 29 wallclock secs (27.91 usr +  0.18 sys = 28.09 CPU) @ 178.00/s (n=5000)
       md5: 27 wallclock secs (25.20 usr +  0.19 sys = 25.39 CPU) @ 196.93/s (n=5000)