php - Creation of new process for each request of web page?

Question

It might be a basic question but everytime a user call a php file from a server, does it create a new process from that server ?

For example, I have a basic form (let's say on index.php) that submits a text to another php file. In that php file, I print the posix_getpid().

I opened in two tabs my index.php an filled in and submitted a text and I ended up with two different pid on each tab.

Which lead me to the conclusion that a server probably create a new process for each script. Am I right ?

Cheers !

Answer 1

I assume that you're running apache as your web server.

When a request comes in, apache starts a new thread. PHP is then invoked on this new thread, hence why you get a new process id every time.

This is, of course, greatly simplified.

I recommend reading this article for a deeper understanding.

Edit: It seems that the process differs between platforms. It works the way I described above on Windows, but multiple apache processes are executed on Unix.