An information processing device of a multiprocessor configuration that can increase significantly the processing capability of read requests. The information processing device comprises a plurality of processing units, a plurality of cache memories for storing temporarily the data read by the plurality of processing units from respective main memories in combination with tag information indicating the state of the data that will be stored, and a system controller for controlling the access of the plurality of processing units to the main memories. The system controller comprises a tag copy unit for holding a copy of the tag information that will be stored in the cache memory, a plurality of write cues for storing write requests, and a store buffer for storing the arbitration results relating to a plurality of write requests that will be stored in the plurality of write cues.