use strict;
use warnings;
use Encode qw( _utf8_on );
use Benchmark::Timer;
use Devel::Peek;

my $timer = Benchmark::Timer->new;

my $latin1 = "foo";
my $utf8   = "foo";
_utf8_on($utf8);
my %latin1_hash = ( $latin1 => 1 );
my %utf8_hash   = ( $utf8   => 1 );
warn "===================================\n";
warn "Latin-1 hash key:\n----------------------------------\n";
Dump \%latin1_hash;
warn "===================================\n";
warn "UTF-8 hash key:\n-----------------------------------\n";
Dump \%utf8_hash;
warn "===================================\n";

for my $iter ( 1 .. 10 ) { 
    my $total = 0;
    $timer->start("Latin-1 hash key, Latin-1 probe");
    $total += $latin1_hash{$latin1} for 1 .. 1_000_000;
    $timer->stop("Latin-1 hash key, Latin-1 probe");

    $total = 0;
    $timer->start("Latin-1 hash key, UTF-8 probe");
    $total += $utf8_hash{$latin1} for 1 .. 1_000_000;
    $timer->stop("Latin-1 hash key, UTF-8 probe");

    $total = 0;
    $timer->start("UTF-8 hash key, Latin-1 probe");
    $total += $latin1_hash{$utf8} for 1 .. 1_000_000;
    $timer->stop("UTF-8 hash key, Latin-1 probe");

    $total = 0;
    $timer->start("UTF-8 hash key, UTF-8 probe");
    $total += $utf8_hash{foo} for 1 .. 1_000_000;
    $timer->stop("UTF-8 hash key, UTF-8 probe");
}

warn scalar $timer->reports . "\n";