An example is when there are a huge number of scalars having random contents. Here compressed storable has 33% over head, where as compressed json has 70%+ overhead.

use strict;
use warnings;

use Storable;
use IO::Compress::Gzip qw(gzip);
use JSON::XS;

my (@data,$serial,$gzserial,$json,$gzjson,$i);

for($i=0;$i<100000;$i++) { push @data, chr(int(rand(256)))}

$serial = Storable::nfreeze(\@data);
$json = encode_json(\@data);

gzip \$json => \$gzjson;
gzip \$serial => \$gzserial;

print scalar(@data)."\n";
print length($serial)."\n"; 
print length($gzserial)."\n";
print length($json)."\n";
print length($gzjson)."\n";
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