A novel and useful mechanism and method for writing data updates to a data cache subsystem of a storage controller. The lattice structure includes two structural regions which are arranged on both sides of the waveguide ridge and are formed at a distance from the laser layer above the laser layer. The diode’s polarity allows current to pass from the direction of the second input terminal. A pin locates the tool relative to the stator slide, and establishes a reaction point for forces applied by the drive block to the stator slide. Furthermore, a demand-supply scheme is planned and changed so as to maximize a profitability index that is calculated by using a cost regarding the production of a product that includes a material cost, a manpower cost, and an equipment cost, a stock management cost, a transportation cost, etc. In addition, the control unit performs control so as to cause a period from starting readout of the signal of the predetermined line to starting next readout of the signal of the predetermined line in the first mode to be the same as that from starting readout of the signal of the predetermined line to starting next readout of the signal in the second mode.