les on disk.  In
        addition to these files, transactional DB applications create
        logs that are also by default stored on disk (they can optionally
        be backed using shared memory). Finally, transactional
        DB applications also create and use shared-memory regions that
        are also typically backed by the filesystem. But like databases and
        logs, the regions can be maintained strictly in-memory if your
        application requires it. For an example of an application that