In addition to the answers you got refuting load as a problem: "Last updated since" headers are indeed a thing. Look for example at how RSS gets cached in wordp

In addition to the answers you got refuting load as a problem: "Last updated since" headers are indeed a thing. Look for example at how RSS gets cached in wordpress [0] or the classical blog engine serendipity [1]. Also, push instead of pull is also common. Made popular for feeds by pubsubhubbub, since enterprise-ready renamed to WebSub [2]. Readers like bazqux do support that. [0]: https://github.com/WordPress/WordPress/blob/270f2011f8ec7265c3f4ddce39c77ef5b496ed1c/wp-includes/rss.php#L471 https://github.com/WordPress/WordPress/blob/270f2011f8ec7265... [1]: https://github.com/s9y/Serendipity/blob/e2044472c202a8368774282264b9d55286cb636c/rss.php#L69 https://github.com/s9y/Serendipity/blob/e2044472c202a8368774... [2]: https://en.wikipedia.org/wiki/WebSub https://en.wikipedia.org/wiki/WebSub