my ($ptid, $total, $used, $avail, $pct, $mp) = $element =~
      m!^(/dev/.+[0-9]+)      # which partition $ptid
          \s+([0-9.]+[MGK])   # total size of parition $total
          \s+([0-9.]+[MGK])   # used space $used
          \s+([0-9.]+[MGK])   # available space $avail
          \s+(\d{2})%         # percent usage $pct
          \s+(.*)$!x;         # mounting point $mp