What are the implications of the session garbage collection settings in PHP and how do they affect session expiration?

Session garbage collection settings in PHP determine how often expired session data is removed from the server to free up resources. If the garbage collection settings are not properly configured, expired session data may accumulate and consume server resources unnecessarily. To ensure efficient session expiration, it is important to set appropriate values for session.gc_probability and session.gc_divisor in the php.ini file.

// Set session garbage collection probability to 1 and divisor to 100
ini_set('session.gc_probability', 1);
ini_set('session.gc_divisor', 100);