We actually keep the sessions very light, and if I could I'd get rid of them entirely. For caching I'm just using nginx and generating as much content to disk

We actually keep the sessions very light, and if I could I'd get rid of them entirely. For caching I'm just using nginx and generating as much content to disk as possible. It is much simpler that way, and the goal is to keep things simple and cheap so I can bootstrap the site.