use strict; use warnings; use Benchmark 'cmpthese'; my $string = map { ('a'..'z')[rand 26] } 1..30; my @sub_fields; cmpthese( -1, { regex1 => sub { @sub_fields = $string =~ /\w{5}/g }, regex2 => sub { @sub_fields = $string =~ /.{5}/g }, unpack => sub { @sub_fields = unpack '(A4)*', $string }, substr => sub { @sub_fields = map { substr $string, 5*$_, 5 } 0..length( $string )/5-1 }, }); #### Rate substr unpack regex1 regex2 substr 696486/s -- -57% -94% -94% unpack 1603093/s 130% -- -85% -86% regex1 10731041/s 1441% 569% -- -4% regex2 11165392/s 1503% 596% 4% --