SEQUENCE STORAGE CIRCUIT

PURPOSE:To ensure the high-speed operation of a computer system by inhibiting the replacement of the data on an area having a high using frequency in a CPU and holding said data in a high-speed memory. CONSTITUTION:When the replacement of data is carried out between a main storage device B and a high-speed storage device A, a 1st replacement means E replaces the replacement sequence stored in a storage means D and defines a area where the replacement is performed as that having the latest replacement sequence. While a 2nd replacement means F replaces the replacement sequence stored in the means D and defines a storage area where data are read out as that having the latest replacement sequence in case the data on the storage device A are read out of a CPU C. As a result, the data having high using frequencies of the CPU C are not easily replaced and remain in the storage device A with high probability. Thus the high-speed operation is secured for a computer system.