What is PHP-FPM

PHP-FPM stands for PHP FastCGI Process Manager. It is a PHP FastCGI (Common Gateway Interface) implementation that is designed to enhance the performance and efficiency of PHP-based web applications. PHP-FPM works in conjunction with a web server to handle PHP requests, manage PHP processes, and execute PHP code.

Traditionally, when PHP is used with a web server like Apache or Nginx, it runs as an Apache module (mod_php) or as CGI (Common Gateway Interface). These methods have some limitations in terms of performance and resource management. PHP-FPM was introduced to address these limitations and provide better performance and control.

Here are some key features and benefits of PHP-FPM:

1. Process Manager: PHP-FPM has its own process manager that handles PHP requests separately from the web server’s main process. This allows PHP processes to be managed independently, reducing the risk of a single request affecting the entire server.
2. Improved Performance: PHP-FPM can efficiently manage PHP processes in a pool, allowing them to be reused for multiple requests, reducing the overhead of creating and destroying processes for each request. This results in improved performance and reduced response times for PHP applications.
3. Resource Management: PHP-FPM provides control over how PHP processes are managed and how resources are allocated, making it easier to optimize server resources based on the application’s needs.
4. Process Isolation: PHP-FPM allows for process isolation, so if a PHP process encounters an issue, it won’t affect other processes or the entire web server.
5. Tunable Configuration: PHP-FPM allows administrators to configure various parameters, such as the number of child processes, maximum requests per process, and more, to fine-tune PHP-FPM’s behavior based on the server’s hardware and application requirements.
6. Log and Status Monitoring: PHP-FPM generates its logs, allowing administrators to monitor the performance of PHP processes and identify potential issues.

PHP-FPM is often used in high-traffic websites and applications where performance and scalability are critical. It is commonly used with web servers like Nginx, Apache, and LiteSpeed to efficiently handle PHP requests.

To use PHP-FPM, you need to install the PHP-FPM package, which is typically available as a separate package from the main PHP installation. Configuration files for PHP-FPM are separate from the main PHP configuration, and they are located in a directory like /etc/php/{version}/fpm/. Once installed and configured, PHP-FPM will work alongside your web server to process PHP requests efficiently and improve the overall performance of PHP applications.