1. A multiprocessor system, comprising: at least two processors connected by a node controller (NC), wherein the NC is used to transfer data requests between the processors, and wherein each of the processors has a dedicated cache for storing data, a pseudo cache agent (PCA) which is located in the NC conforming to a processor micro-architecture level interconnect protocol, wherein the PCA is configured to: pre-fetch target data from a dedicated cache controlled by one of the processors, when network is idle, and write the target data into a PCA storage device, wherein the PCA storage device is coupled to the PCA and is dedicated to the PCA, and wherein the PCA storage device is accessible only to the PCA, wherein a first processor is configured to: receive a data request which includes an address of the target data, determine whether the target data is stored in a dedicated cache corresponding to the first processor based on the address, and send the data request to the NC to instruct the NC to forward the data request to a second processor if the target data is not stored in the dedicated cache corresponding to the first processor, and wherein the PCA is further configured to: receive the data request from the first processor, determine that the target data is stored in the PCA storage device based on the address, obtain the target data from the PCA storage device, and send the target data to the first processor.