Why aren't my php.ini changes taking effect?

In this article:

Our VPS run FastCGI which causes certain scripting processes to execute for long period of time to increase performance.  

Because the php.ini script is only read when a script starts up this can cause changes to your php.ini file to not take effect right away.  

To force a restart of all PHP processes for your hosted domain you can click on the "Restart PHP" link found on the "Hosting Home" page of our control panel.

More on PHP:

How can I alter my own PHP configuration file?

Can I change the version of PHP that I run?