H2 is here. Did you hear? For anyone who's not heard, yes - Httpbis aka H2 aka RFC 7540 better known as HTTP2 has been a buzz word for more than a few and there is quite a hefty share of docs and talks populating the web to prove it. As adoption slowly grows, it has been heralded as one the more significant advancements performance updates seeing that it replaces a networking protocal long in the tooth, and enjoys wide support. Among much of the discussed features coming is H2 Push - permitting the server to send the data prior to the request actually being made.
Adding to the library of available docs covering this topic is an extremely well detailed post by Robin Marx exploring the low-level issues that determine how useful push can be as well as how this impacts practical usage.
The university researcher covers the A-Z of the protocol's feature in finite detail worth reading and bookmarking for reference.
You can read the post as part of the Performance Calendar here.