php-cgi和php-fpm之间有什么关系？

Question

When we use nginx as webserver, we also use php-fpm. If we use apache or lighttpd, we talk php-cgi more. So the question is what relationship and difference between php-cgi and php-fpm? Thanks very much.

Answer 1

PHP-CGI is a CGI interface. PHP-FPM is a FastCGI interface.

CGI gets run once per request. FastCGI gets run once, at server startup, then enters a request loop. This makes CGI simpler, as it has no dependencies; FastCGI is faster, since it avoids any start-up times, but it's a bit more complex to set up.