Session.php
public function gc($maxLife)
    {
        $db = Database::database();
        return $db->prepare('DELETE FROM sessions WHERE (UNIX_TIMESTAMP(session_expires) + ? ) < UNIX_TIMESTAMP(?)')->execute([$maxLife, date('Y-m-d H:i:s')]) ?
            true : false;
    }
public function gc($maxLife)
    {
        $db = Database::database();
        return $db->prepare('DELETE FROM sessions WHERE (UNIX_TIMESTAMP(session_expires) + ? ) < UNIX_TIMESTAMP(?)')->execute([$maxLife, date('Y-m-d H:i:s')]) ?
            true : false;
    }
This is our garbage collector. If a session is expired attempt to remove it.
This function is executed via a probability. See link for more details.
@link http://php.net/manual/en/features.gc.php
@param int $maxLife
@return bool