caching extension for 'stale' data
mark nottingham has posted his plan to revive some excellent HTTP caching extensions.
stale-while-revalidate allows proxies to continue to deliver stale content while the proxy goes back to the origin server for a fresh copy. this can be configured to perform an 'on-demand pre-fetch' style update.
stale-if-error tells the proxy it can continue to deliver stale content for a fixed period of time while receiving HTTP 500 errors. this is especially handy in Ajax/RSS environments where other servers are down while your server attempts to compose the page.
i esp. like the first proposal. i've been struggling with some potential caching issues that will be greatly helped by supporting this extension.
now i just need to think about how to implement it for my local server...