With HTTP/2 push you can effectively send a web page’s assets to the client before the client even knows about them. Here’s how you can HTTP/2 push WordPress assets to your first-time visitors.
Recently, I’ve done some WordPress load optimization and to achieve full effect, you do have to load the Google Analytics tracking script, ga.js, from your own server.
SPDY is this new, cool, fast protocol created by Google that “replaces” HTTP (the first draft of HTTP 2.0 is using SPDY as the working base). It is supported in all the major browsers – yes, even Internet Explorer – with the exception of Apple’s Safari.
TL;DR: Varnish lacks support for SSL and SPDY. Nginx handles it just fine, and has very fast cache with either memcache or disk storage (ramdisk). Both can serve stale cache if your backend is down. But Nginx can not write to the memcache storage directly, it has to be done by the application. Also, Nginx …