Go to System → Settings → System
Because every system is setup differently, phpinfo() is commonly used to check configuration settings and for available predefined variables on a given system.
Outputs a large amount of information about the current state of PHP. This includes information about PHP compilation options and extensions, the PHP version, server information and environment (if compiled as a module), the PHP environment, OS version information, paths, master and local values of configuration options, HTTP headers, and the PHP License.
For example, you may need to update your php memory_limit to prevent certain scripts from running out of memory. In order to change these values, you must first be able to see what they are.