title: How to generate sitemap on a highly dynamic website?
body: <p>Should a highly dynamic website that is constantly generating new pages use a <a href="http://en.wikipedia.org/wiki/Site_map" rel="noreferrer">sitemap</a>? If so, how does a site like stackoverflow.com go about regenerating a sitemap? It seems like it would be a drain on precious server resources if it was constantly regenerating a sitemap every time someone adds a question. Does it generate a new sitemap at set intervals (e.g. every four hours)? I'm very curious how large, dynamic websites make this work.</p>