After ages of solely using mod_php in ISPConfig, I've been digging into the details more. First of all, I found out that combinding SuExex with mod_php doesn't accomplish much: PHP is still run as the HTTPD user and not as the web-user. And then there's Fast-CGI and PHP-FPM. I found various sources that seem to suggest that PHP-FPM would be faster than Fast-CGI. However, when I switched a website over to PHP-FPM, I noticed that a whopping 20 new PHP-FPM processes are started for the new pool (web24 in this case), even before accessing the website itself. This seems a little overwhelming and I can hardly believe this will scale up when I would switch over all sites to PHP-FPM. Fast-CGI on the other hand does not seem to launch additional processes until the page is accessed and the processes also terminated after a short while. This seems to be much nicer on system resources when hosting numerous websites. Is my observation correct? Is there anything to improve the situation for PHP-FPM or is it just better to stick with Fast-CGI?