Menu
What makes a difference from CGI is that with FastCGI the running process of the application lasts longer and it is not immediately terminated. After the application finishes processing and returns the output data, the process is not terminated and is being used for processing further requests.
FastCGI is a programming interface that can speed up Web applications that use the most popular way to have the Web server call an application, the common gateway interface (CGI).
Conclusion. PHP-FPM is an efficient method on how to minimize the memory consumption and rise the performance for the websites with heavy traffic. It is significantly faster than traditional CGI-based methods in multi-user PHP environments.
php-fpm ist running in its own process all the time. It can use apc because it uses continuously the ram over several requests. The memory is only released through the garbage collector or if you kill the fpm process. But the a CLI process lives only for one command and when its finished the memory is released.
FPM is a process manager to manage the FastCGI SAPI (Server API) in PHP.
Basically, it replaces the need for something like SpawnFCGI. It spawns the FastCGI children adaptively (meaning launching more if the current load requires it).
Otherwise, there's not much operating difference between it and FastCGI (The request pipeline from start of request to end is the same). It's just there to make implementing it easier.
What Anthony says is absolutely correct, but I'd like to add that your experience will likely show a lot better performance and efficiency (due not to fpm-vs-fcgi but more to the implementation of your httpd).
For example, I had a quad-core machine running lighttpd + fcgi humming along nicely. I upgraded to a 16-core machine to cope with growth, and two things exploded: RAM usage, and segfaults. I found myself restarting lighttpd every 30 minutes to keep the website up.
I switched to php-fpm and nginx, and RAM usage dropped from >20GB to 2GB. Segfaults disappeared as well. After doing some research, I learned that lighttpd and fcgi don't get along well on multi-core machines under load, and also have memory leak issues in certain instances.
Is this due to php-fpm being better than fcgi? Not entirely, but how you hook into php-fpm seems to be a whole heckuva lot more efficient than how you serve via fcgi.
Running PHP as a CGI means that you basically tell your web server the location of the PHP executable file, and the server runs that executable
whereas
PHP FastCGI Process Manager (PHP-FPM) is an alternative FastCGI daemon for PHP that allows a website to handle strenuous loads. PHP-FPM maintains pools (workers that can respond to PHP requests) to accomplish this. PHP-FPM is faster than traditional CGI-based methods, such as SUPHP, for multi-user PHP environments
However, there are pros and cons to both and one should choose as per their specific use case.
I found info on this link for fastcgi vs fpm quite helpful in choosing which handler to use in my scenario.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With