use Devel::Size qw(size);
$foo = 2;
while ($foo--) {
  {
    my $bar;
    print Devel::Size::size(\$bar), " ", length($bar), "\n";
    $bar = " " x 10000000;
  }
}

##</code><code>##

12 0
10000025 0

##</code><code>##

12 0
12 0