use Benchmark qw(:all);
use File::Slurp;

$file_slurp = sub { $file = read_file('arq.pdf', binmode => ':raw') };
$read       = sub { open $file, '<', 'arq.pdf' || die $!; read $file, $data, -s 'arq.pdf'; close $file; };
timethese(1000, { file_slurp => $file_slurp, read => $read, });
cmpthese(1000, { file_slurp => $file_slurp, read => $read, });