use Benchmark qw(:all);

my $a = 10;
my $b = 20;

cmpthese(-2, {
        'Sub' => sub {
            my $c = add ($a, $b);
        },
        'Method' => sub {
            my $c = __PACKAGE__->meth_add ($a, $b);
        },
        'Sub^2' => sub {
            my $c = add2 ($a, $b);
        },
        'Method^2' => sub {
            my $c = __PACKAGE__->meth2 ($a, $b);
        },
        'Method^3' => sub {
            my $c = __PACKAGE__->meth3 ($a, $b);
        },
    });

sub add {
    return $_[0] + $_[1];
}

sub add2 {
    $_[0] + $_[1]
}

sub meth_add {
    shift;
    return $_[0] + $_[1];
}

sub meth2 {
    shift;
    $_[0] + $_[1]
}

sub meth3 {
    $_[1] + $_[2]
}