use strict; use Benchmark; my %h; my @a = ('a'..'zzz'); @h{@a} = (1) x @a; timethese('-10', { find_array => sub { return (grep /^ccc$/, @a) ? 1 : 0 }, find_hash => sub { return $h{'ccc'} }, iterate_array => sub { do {} for @a }, iterate_hash => sub { do {} for keys %h }, }); __END__ yields on my dual proc 400 linux box: (YMWV) find_array: 10 wallclock secs (10.11usr + 0.04sys = 10.15 CPU) @ 45.62/s (n=463) find_hash: 13 wallclock secs (11.41usr + 0.07sys = 11.48 CPU) @ 1183591.72/s (n=13587633) iterate_array: 11 wallclock secs (10.98usr + 0.09sys = 11.07 CPU) @ 70.28/s (n=778) iterate_hash: 11 wallclock secs (10.78usr + 0.05sys = 10.83 CPU) @ 16.53/s (n=179)