The comparison code of the OP also includes the time taken to generate a large scalar for each test iteration. Stripped-down code makes the point more forcefully. 
use strict;
use warnings;

use Benchmark qw(cmpthese);


my $long_string = 'aaaaaaaaaaaaaaaaaaaaaaaa' x 1000000;
my $destination;


sub return_scalar { return  $long_string }
sub return_ref    { return \$long_string }


cmpthese(
    -1,
    {   'scalar' => sub { $destination = return_scalar() },
        'ref'    => sub { $destination = return_ref   () },
        }
    );

[download]
Result: 
            Rate   scalar      ref
scalar    22.2/s       --    -100%
ref    1612824/s 7250890%       --

[download]

In reply to Re: Does the reference of a scalar more efficient than scalar? by AnomalousMonk
in thread Does the reference of a scalar more efficient than scalar? by sunshine_august

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