Method and storage array for procesing a write data request

A method for processing a write data request in a storage array comprising an input/output manager, a switching device, a first controller, and a first cache device, and wherein the input/output manager, the first controller and the first cache device are coupled to the switching device, and the switching device is coupled to a storage unit in the storage array;

• the method comprising:
• obtaining, by the first controller for a write data request from the input/output manager via the switching device, a first cache address in the first cache device for storing an incoming data block of the write data request;
• sending, by the first controller, an identifier of the first cache device and the first cache address to the input/output manager, via the switching device;
• and
• writing, by the input/output manager, the incoming data block of the write data request to the first cache address via the switching device according to the identifier of the first cache device and the first cache address;
• calculating, by the cache device, an eigenvalue of the incoming data block;
• sending, by the cache device, the eigenvalue of the incoming data block to the first controller via the switching device;
• receiving, by the first controller, the eigenvalue of the incoming data block;
• searching, by the first controller, an eigenvalue index set of previously processed data blocks for the eigenvalue of the incoming data block;
• wherein the eigenvalue index set comprises a plurality of eigenvalue indices each comprising an eigenvalue of a respective data block in the previously processed data blocks and a storage address of the respective data block in a respective target storage unit, each of the previously processed data blocks being unique among the previously processed data blocks;
• when the eigenvalue of the incoming data block is not in the eigenvalue index set, storing, by the first controller, the incoming data block into a target storage unit;
• creating, by the first controller, an eigenvalue index of the incoming data block in the eigenvalue index set of data blocks, wherein the eigenvalue index of the incoming data block comprises the eigenvalue of the incoming data block and the storage address of the incoming data block in the target storage unit.