Apache with PHP-FPM on Debian and Ubuntu

Apache‘s default and easiest implementation of PHP mod_php consumes a lot of system resources. It is loaded by Apache even when non-PHP files (like plain HTML and JavaScript) are requested. Configuring PHP-FPM (FastCGI Process Manager) solves this problem by making the web server act like a proxy which passes only *.php requests to the backend PHP-FPM.
Configuring PHP-FPM has another advantage; each virtual host can be configured to run PHP code as a different user. This was previously possible only with suPHP.

Installing mod_fastcgi and PHP-FPM
Configuring Apache with PHP-FPM
Advanced Configuration
Configuring PHP Pools
More Information

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