[xzyfer]

Browser do currently do this. H2 has two types of prioritisations: weighted, and dependency.

All browsers implement weighted resource prioritisation and weigh resources by content type. This is a hold over from what they do for HTTP/1 connections.

Firefox has dependency resources prioritisation. https://bitsup.blogspot.com.au/2015/01/http2-dependency-prio...

The spec purposely leave how these heuristics should work to the implementor. Things will change and implementations will diverge over time.

The server ultimately being in control means we can tell the server what resources are important for specific pages with absolute knowledge of the page.

[foota]

Oh wow, that's cool. Do you know if servers currently support this? Would this mostly be useful on a network level or do you think it would also be useful for like trying to be more intelligent about scheduling?

[xzyfer]

It's hard to say for sure. Server implementations can vary wildly, make sure to test any implementation closely. I know from talking to CloudFlare that their implementation respects browser hints. Their implementation is also open source.