Change session expiration
ini_set('session.cookie_lifetime', 60 * 60 * 24 * 7); // 7 day cookie lifetime
ini_set('session.gc_maxlifetime', 60 * 60 * 24 * 7);
ini_set('session.save_path', '/home/yoursite/sessions');
session_start();
setcookie('PHPSESSID','any id' , any time);