Storage management for fine grained tiered storage with thin provisioning

A system for managing data includes providing at least one logical device having a table of information that maps sections of the logical device to sections of at least two storage areas. Characteristics of data associated with a one section of the logical device may be evaluated. The section of the data may moved between the at least two storage areas from a first location to a second location according to a policy and based on the characteristics of the data. A copy of the data may be retained in the first location and a list maintained that indentifies the copy of the data in the first location. The system provides for garbage collection processing for memory management.