How do you calculate server load in PHP?

Question

How do you calculate the server load of PHP/apache? I know in vBulletin forums there's the server load displayed like 0.03 0.01 0.04 but it's not really understandable to a average joe. So I thought about a 1-100 percentile scale. I wanted to display a server load visual that reads from a DIV:

$load = $serverLoad*100;
<div class=\"serverLoad\">
    <div style=\"width: $load%;\"></div>//show visual for server load on a 1-100 % scale
</div>
<p>Current server load is $load%</p>
</div>

However, I don't know how to detect server load. Is it possible to do turn this server load into a percentile scale? I don't know where to start. May someone please help me out?

Thanks.

The reason that the three values exist is that a single percentage metric doesn't really tell you anything. — Lightness Races in Orbit, Apr 07 '11 at 23:08

score 14 · Accepted Answer · answered Apr 07 '11 at 23:13

I have a very old function that should still do the trick:

function getServerLoad($windows = false){
    $os=strtolower(PHP_OS);
    if(strpos($os, 'win') === false){
        if(file_exists('/proc/loadavg')){
            $load = file_get_contents('/proc/loadavg');
            $load = explode(' ', $load, 1);
            $load = $load[0];
        }elseif(function_exists('shell_exec')){
            $load = explode(' ', `uptime`);
            $load = $load[count($load)-1];
        }else{
            return false;
        }

        if(function_exists('shell_exec'))
            $cpu_count = shell_exec('cat /proc/cpuinfo | grep processor | wc -l');        

        return array('load'=>$load, 'procs'=>$cpu_count);
    }elseif($windows){
        if(class_exists('COM')){
            $wmi=new COM('WinMgmts:\\\\.');
            $cpus=$wmi->InstancesOf('Win32_Processor');
            $load=0;
            $cpu_count=0;
            if(version_compare('4.50.0', PHP_VERSION) == 1){
                while($cpu = $cpus->Next()){
                    $load += $cpu->LoadPercentage;
                    $cpu_count++;
                }
            }else{
                foreach($cpus as $cpu){
                    $load += $cpu->LoadPercentage;
                    $cpu_count++;
                }
            }
            return array('load'=>$load, 'procs'=>$cpu_count);
        }
        return false;
    }
    return false;
}

This returns processor load. You can also use memory_get_usage and memory_get_peak_usage for memory load.

If you can't handle finding percentages based on this... sigh, just post and we'll try together.

score 9 · Answer 2 · answered Sep 05 '12 at 12:44

9

This function in PHP might do that trick: sys_getloadavg().

Returns three samples representing the average system load (the number of processes in the system run queue) over the last 1, 5 and 15 minutes, respectively.

answered Sep 05 '12 at 12:44

jakubos

105
1
7

I think this might be OS specific. – kloddant Aug 10 '22 at 13:34

score 3 · Answer 3 · answered Apr 07 '11 at 23:36

function get_server_load()
{

    $serverload = array();

    // DIRECTORY_SEPARATOR checks if running windows
    if(DIRECTORY_SEPARATOR != '\\')
    {
        if(function_exists("sys_getloadavg"))
        {
            // sys_getloadavg() will return an array with [0] being load within the last minute.
            $serverload = sys_getloadavg();
            $serverload[0] = round($serverload[0], 4);
        }
        else if(@file_exists("/proc/loadavg") && $load = @file_get_contents("/proc/loadavg"))
        {
            $serverload = explode(" ", $load);
            $serverload[0] = round($serverload[0], 4);
        }
        if(!is_numeric($serverload[0]))
        {
            if(@ini_get('safe_mode') == 'On')
            {
                return "Unknown";
            }

            // Suhosin likes to throw a warning if exec is disabled then die - weird
            if($func_blacklist = @ini_get('suhosin.executor.func.blacklist'))
            {
                if(strpos(",".$func_blacklist.",", 'exec') !== false)
                {
                    return "Unknown";
                }
            }
            // PHP disabled functions?
            if($func_blacklist = @ini_get('disable_functions'))
            {
                if(strpos(",".$func_blacklist.",", 'exec') !== false)
                {
                    return "Unknown";
                }
            }

            $load = @exec("uptime");
            $load = explode("load average: ", $load);
            $serverload = explode(",", $load[1]);
            if(!is_array($serverload))
            {
                return "Unknown";
            }
        }
    }
    else
    {
        return "Unknown";
    }

    $returnload = trim($serverload[0]);

    return $returnload;
}

score 2 · Answer 4 · answered Apr 15 '11 at 14:18

If "exec" is activated

/**
 * Return the current server load
 * It needs "exec" activated
 *
 * e.g.
 * 15:06:37 up 10 days,  5:59, 12 users,  load average: 1.40, 1.45, 1.33
 * returns
 * float(1.40)
 */
public function getServerLoad()
{
    preg_match('#(\d\.\d+),[\d\s\.]+,[\d\s\.]+$#', exec("uptime"), $m);
    return (float)$m[1];
}

score 1 · Answer 5 · answered Apr 25 '15 at 16:12

Here is a windows/linux compatible php server load function:

function get_server_load() {
    $load = '';
    if (stristr(PHP_OS, 'win')) {
        $cmd = 'wmic cpu get loadpercentage /all';
        @exec($cmd, $output);
        if ($output) {
            foreach($output as $line) {
                if ($line && preg_match('/^[0-9]+$/', $line)) {
                    $load = $line;
                    break;
                }
            }
        }

    } else {
        $sys_load = sys_getloadavg();
        $load = $sys_load[0];
    }
    return $load;
}

score 1 · Answer 6 · answered Apr 14 '16 at 05:46

1

<?php
$load = sys_getloadavg();
if ($load[0] > 0.80) {
    header('HTTP/1.1 503 Too busy, try again later');
    die('Server too busy. Please try again later.');
}
?>

answered Apr 14 '16 at 05:46

SagarPPanchal

9,839
6
34
62

1

While this code snippet may solve the question, [including an explanation](http://meta.stackexchange.com/questions/114762/explaining-entirely-code-based-answers) really helps to improve the quality of your post. Remember that you are answering the question for readers in the future, and those people might not know the reasons for your code suggestion. - [From review](https://stackoverflow.com/review/low-quality-posts/12011689) – Ferrybig Apr 14 '16 at 07:49
1

appreciative! thank you for your guide, will definitely keep in mind – SagarPPanchal Apr 14 '16 at 09:19

M_R_K · Answer 7 · 2013-07-26T15:22:18.193

0

Its Pretty easy in LAMP environment if you have proper permissions,

print_r(sys_getloadavg());

OUTPUT : Array ( [0] => 0 [1] => 0.01 [2] => 0.05 )

Array values are average load in the past 1, 5 and 15 minutes respectively.

edited Jul 26 '13 at 15:22

answered Jul 26 '13 at 15:01

M_R_K

5,929
1
39
40

score -1 · Answer 8 · answered May 07 '13 at 19:53

-1

function _loadavg()
{
    if(class_exists("COM")) 
    {
      $wmi = new COM("WinMgmts:\\\\.");
      $cpus = $wmi->InstancesOf("Win32_Processor");

      foreach ($cpus as $cpu) 
      {
       return $cpu->LoadPercentage;
      }
    } 
}

answered May 07 '13 at 19:53

Musznik

94
2
5

How do you calculate server load in PHP?

8 Answers8