use strict;
use Benchmark;

my $len = 4000;
my @data = ();
push(@data,rand()) for (0..$len);

timethese(2000, {
    'by_whole' => sub {
        my @copy = sort_by_array(@data);
    }
    ,
    'by_refs' => sub {
        my @copy = sort_by_ref(\@data);
    }

});

sub sort_by_array
{
    return sort {$a <=> $b} @_;
}

sub sort_by_ref
{
    return sort {$a <=> $b} @{$_[0]};
}

__END__


Benchmark: timing 2000 iterations of by_refs, by_whole...
by_refs: 54 wallclock secs (42.80 usr +  0.01 sys = 42.81 CPU) @ 46.72/s (n=2000)
by_whole: 44 wallclock secs (43.02 usr +  0.00 sys = 43.02 CPU) @ 46.49/s (n=2000)