use Devel::Size 'total_size';
my $num=1000;
print total_size($num) . $/;
print total_size(pack("w*",$num)) . $/;

[download]

the output is: 

24
48

[download]

why?

update

the result become 

48
48

[download]

if I put it into a file

In reply to Why is the size even bigger after pack? by PerlOnTheWay

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