Method, device and system for data processing

The invention relates to the technical field of data processing, in particular to a method, a device and a system for data processing. The method for the data processing includes providing a first interface which receives a file write operation request from an application program; portioning the data of a file into at least one sub-data block, obtaining an unique identification of each of the at least one sub-data block, and comparing unique identifications with a reserved unique identification; establishing a chaining between a sub-data block identical to the reserved unique identification and the data corresponding to the reserved unique identification if the unique identifications are identical to the reserved unique identification; and otherwise, reserving the unique identifications of the sub-data block, which are different from the reserved unique identification, sending a data write operation request including the data of the sub-data block, which are different from the reserved unique identification, to a storage system by means of a second interface, and enabling the storage system to store the data of the sub-data block. According to the method, the device and the system for the data processing, the repeated data are reduced, and the storage space is saved.