Due to the method in which navigation links are defined, it is important to avoid creating complex navigation page specs that would result in an overwhelming number of unique links. Such a scenario may cause excessive memory usage by the Sitemap Generator, as well as long runtimes to write all of the specified links. Oracle strongly recommends that only two or fewer dimensions be specified in the main configuration file for any given <NAVIGATION_PAGE_SPEC>. Otherwise, it is possible to generate millions of navigation links and reduce the site's search engine ranking by making it appear to be a link farm.