librenms-librenms/includes/polling/processors.inc.php

<?php

$query = "SELECT * FROM processors WHERE device_id = '" . $device['device_id'] . "'";
$proc_data = mysql_query($query);
while($processor = mysql_fetch_array($proc_data)) {

  echo("Checking CPU " . $processor['processor_descr'] . "... ");

  $file = $config['install_dir']."/includes/polling/processors-".$processor['processor_type'].".inc.php";
  if(is_file($file)) {
    include($file);
  } else {
    $proc = snmp_get ($device, $processor['processor_oid'], "-O Uqnv");
  }

  $procrrd  = $config['rrd_dir'] . "/" . $device['hostname'] . "/" . safename("processor-" . $processor['processor_type'] . "-" . $processor['processor_index'] . ".rrd");

  if (!is_file($procrrd)) {
   shell_exec("rrdtool create $procrrd \
     --step 300 \
     DS:usage:GAUGE:600:-273:1000 \
     RRA:AVERAGE:0.5:1:1200 \
     RRA:MIN:0.5:12:2400 \
     RRA:MAX:0.5:12:2400 \
     RRA:AVERAGE:0.5:12:2400");
  }

  $proc = trim(str_replace("\"", "", $proc));
  list($proc) = preg_split("@\ @", $proc); 

  $proc = round($proc / $processor['processor_precision'],2);

  echo($proc . "%\n");

  rrdtool_update($procrrd,"N:$proc");

  mysql_query("UPDATE `processors` SET `processor_usage` = '$proc' WHERE `processor_id` = '".$processor['processor_id']."'");

}

?>