Ariadne can be run on anything from your desktop computer to IBM mainframes. It can be setup to run on a cluster of webservers, using a single database server or a clustered database system.
Ariadne's unique object storage layer is designed to get the most out of your database system. Even the most complex searches can be done with a single database search on properly indexed tables. No need even to be able to dream in SQL, Ariadne's query language takes most of the pain out of SQL.
The built-in caching system means that even the more complex functionality of Ariadne won't bring down your server. Images and files are automatically sent with client-side caching enabled (you can override this). Enabling the caching system for an entire site is just a matter of a few mouse-clicks. Even if you need personalized content, the 'private cache' in Ariadne helps to keep the load down.
Ariadne's storage layer is database independant. Out of the box Ariadne has support for MySQL, PostgreSQL, with MS-SQL and Oracle almost there. Because of the modular architecture adding support for a new storage system is fairly straightforward.