How to Monitor PHP-FPM

Overview

PHP-FPM (FastCGI Process Manager) is the most widely used PHP process manager for serving PHP applications behind Nginx or Apache. Xitoring's PHP-FPM integration gives you real-time visibility into process pool health, request throughput, and resource consumption.

What Can It Monitor?

Active Processes — Worker processes currently handling requests
Idle Processes — Worker processes waiting for requests
Request CPU — CPU usage per request
Request Memory — Memory usage per request
Listen Queue — Requests waiting for a free worker
Max Listen Queue — Peak queue length since last restart
Slow Requests — Requests exceeding the slow log threshold
Total Processes — Combined active + idle workers
Max Active Processes — Peak concurrent workers since last restart

Prerequisites

You need to enable PHP-FPM's built-in status page before activating the integration.

On Linux

Edit your PHP-FPM pool configuration (e.g., /etc/php/php-fpm.d/www.conf) and uncomment these lines:

pm.status_path = /fpm/status
ping.path = /fpm/ping

Restart PHP-FPM:

sudo systemctl restart php-fpm

On Windows

Edit C:\Program Files\PHP\v7.X\php-fpm.d\www.conf and uncomment the same lines:

pm.status_path = /fpm/status
ping.path = /fpm/ping

Restart the service:

Restart-Service -Name php-fpm

Configure Your Web Server

Nginx

Add this location block to serve the status page locally:

location ~ ^/fpm/(status|ping)$ {
    allow 127.0.0.1;
    deny all;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    fastcgi_index index.php;
    include fastcgi_params;
    fastcgi_pass unix:/var/run/php-fpm/www.sock;
}

Apache

Add a proxy configuration for the status endpoint:

<Location /status>
    ProxyPass unix:/var/run/php-fpm.sock|fcgi://localhost/status
    ProxyPassReverse unix:/var/run/php-fpm.sock|fcgi://localhost/status
    ProxyRequests Off
    AllowOverride None
    Require local
</Location>

Tip: Replace socket paths with values appropriate for your server setup.

How to Activate the Integration

Run the Xitogent CLI:

xitogent integrate

Select PHP-FPM from the list. When prompted, enter the URL where the status page is served:

http://127.0.0.1/fpm/status

Setting Up Triggers

Available trigger parameters:

Active Processes / Idle Processes
Request CPU / Request Memory
Listen Queue
Slow Requests
Total Processes

Navigate to Triggers on your server page, select PHP-FPM, choose the metric, set thresholds, and configure your notification channels.

Tips

Monitor Listen Queue — a growing queue means you need more workers
Set alerts on Active Processes to detect when your pool is saturated
Track Slow Requests to identify performance bottlenecks in your PHP code
Keep the status endpoint restricted to localhost for security
Works on both Linux and Windows servers