Symfony Finland
Random things on PHP, Symfony and web development
It's widely stated that the use of HTTP/2 requires SSL/TLS encryption. This technically not true, but as clients only support HTTP/2 via SSL it's a defacto-requirement. With browser and server support for the new protocol version, the only hurdle is the overhead of setting up encryption.
Varnish is a popular reverse proxy which is used to accelerate page loading by caching copies as static HTML. Varnish does not support SSL/TLS, which is in practise required to take use of the new HTTP/2 protocol. This article describes one way of achieving high performance using Varnish and HTTP/2.
HTTP/2 supports a feature called Server Push. This allows the server to send stylesheets, javascript and other assets to client browsers without separate requests.
Time to first paint is the one of the most critical user experience for web sites. Essentially what this means is the moment the user sees something on their screens after following a link. This gives the perception of a fast load time, and first impressions count on the web.
A week ago I setup this site on HTTP/2 and wrote a short article on running PHP with the H2O server. As a follow-up I decided to write a brief article on how many visitors actually used this new capability on the site.