Systems and methods for restriping files in a distributed file system

Systems and methods for restriping files distributed among a set of smart storage units, wherein data blocks for a particular stripe do not typically need to be located at any particular location on the storage units, wherein data can be typically restriped among the smart storage units with minimal data movement, and wherein data is typically protected and recoverable even if a system failure occurs during the restriping process. One embodiment relates to a method of selecting a storage unit for a block of data. The method comprises identifying storage units on which the block of data is currently stored; identifying an optimal location on first storage unit; determining a set of optimal storage units; if the first storage unit is one of the storage units on which the block of data is currently stored, selecting the first storage unit; and if the first storage unit is not in the list of storage units on which the block of data is currently stored, selecting one of the set of optimal storage units. Another aspect of the present invention relates to a method of restriping data stored in a plurality of smart storage devices in an intelligent distributed file system. The method comprises identifying at least one smart storage device on which clusters of data from an existing file may be stored; storing the clusters on the identified smart storage device; determining that the clusters were successfully stored; and updating metadata related to the clusters of data to reflect new assignments.