#!/usr/local/bin/php
<?php

$average_load = (double)shell_exec("(uptime | awk '{print $10+0}')");
$cpu_count = (int)shell_exec("nproc");

if ($cpu_count <= 8) {

    if ($average_load >= ($cpu_count * 20)) {
        echo "CRITICAL: Load $average_load/$cpu_count";
        exit(2);

    } else {
        echo "OK: Load Average(low cores): $average_load/$cpu_count";
        exit(0);
    }

} else {

    if ($average_load >= ($cpu_count * 1.5)) {

        echo "CRITICAL: Load $average_load/$cpu_count";
        exit(2);

    } else {
        echo "OK: Load Average: $average_load/$cpu_count";
        exit(0);
    }
}