I would like to take this opportunity to describe how Openstack Swift stores data. Swift storage basically consists of four components: Ring, Database, Zones, and File system.
Openstack Swift Accounts, Containers & Objects
Openstack Swift data consists of Accounts, Containers, and Objects. A Swift item then, can be an account, a container, or an object. A Swift Cluster can have multiple accounts, an account can have multiple containers, and a container can have multiple objects. Containers cannot be nested. That is, a container can only contain objects, it can not contain other containers. So Swift storage is considered to be a flat file system.