Project Agape who is behind the Causes Facebook app uses the following:
* mySQL 5.0
* Ruby on Rails
* 14 application servers, 2 database servers and 5 boxes in reserve
* 3 Image Servers (2 Squid, 1 image source)
* Apache 2 on Image Source
* WebApp servers have 2GB of ram
* 1 server for serving static content
* 26 Mongrel services per box
* 4 GB of RAM per box
* 50 - 60 MB of RAM per Mongrel service for a total use of around 1.5 GB of memory set aside for Mongrel
Additional:
* A pair of F5 Loadbalancers
* All systems running FreeBSD 6.2
* memcached
* nginx (not pound)
Thanks - this is useful. I will check out the Causes app.Any ideas on what this kind of setup might cost? Would an ad-network targeted at facebook apps need this much hardware or less - or more even? I have no idea.
Sorry for the late reply. So Causes received about $1.25M in funding, and they only have about five engineers I think. The hardward is always the lowest cost. With an ad network, that will be quite a lot actually especially if you plan to scale to every app imaginable. According to many of those in the top 3% and 1% of facebook apps, it's fairly data intensive, but I think you can scale this pretty easily. I'd start with a smaller amount first and then just scale up with a managed hosting service.
