Pro string handling in PHP

gistfile1.php

$perl = 'if($_ =~ /(\d+)\s*Ram,?\s*(\d+)\s*Cores,?\s*(\d+)%\s*CPU,?\s*(\d+)\s*GB\s*disk/i){ print "$1 $2 $3 $4";}';
$string = `echo $description | perl -ne '$perl'`;
      list ($ram, $cores, $cpu, $disk) = explode(" ", $string);
      $specs[$ram] = array(
      'ram'   => $ram,
      'cores' => $cores,
      'cpu'   => $cpu,
      'disk'  => $disk,
);