In reply to Ryan Hellyer.

Take a look at https://wordpress.org/plugins/nginx-helper/ -- It's a plugin that manages purging the nginx cache at appropriate times for you. It works great.

In addition to the nginx fastcgi cache for non-logged in users, I'm now experimenting with HHVM and redis-backed object caching. HHVM is fast enough that it is worth a little babysitting and implementing work-arounds for its once in a while instability. I run it with php-fpm as a failover.

I had been using memcached with W3 total cache for object caching, but W3 total cache has caused me endless problems and it just seems to me like it is too big and trying to do too much. So I'm now switching over to redis and https://wordpress.org/plugins/redis-cache