Abstract: A control apparatus includes a memory and a processor. The processor sets a comparison reference value on the basis of a first response time of a response to a first command that has been issued to a transmission destination. The processor stores the comparison reference value in the memory. The processor compares, when a second command is to be issued, a differential amount of data flows with the comparison reference value stored in the memory. The differential amount indicates a difference between an amount of data flows related to commands that have been issued to the transmission destination and an amount of data flows related to response data that have been received from the transmission destination. The processor restrains, when the differential amount exceeds the comparison reference value, the second command from being issued.

Abstract: A power supply noise analysis model creation method comprising; obtaining a distance which appears most frequently, from among the distances from a vias judged to be the nearest to the vias, respectively, as a reference via pitch, generates four nodes for the via of target wherein the four nodes generates the middle point with the other four via that are near the via of the target, obtaining meshes which include the nodes, respectively, by dividing the power island structure and the power supply pair by dividing lines which pass between the generated nodes, and converting each of the meshes obtained to a circuit element equivalent to the mesh.

Abstract: A selector calculates a difference between the number of write operations of a first storage medium and that of a second storage medium and takes the difference as a first difference. Further, the selector calculates a difference between the number of write operations of the first storage medium and that of a third storage medium after copying the data within the second storage medium to the third storage medium and takes the difference as a second difference. Then, the selector selects the second storage medium as a target of replacement with which the second difference is larger than the first difference. A setting changer copies the data stored in the second storage medium selected as a target of replacement to the third storage medium, and changes the setting of the second storage medium to a spare and the setting of the third storage medium to a data write destination.

Abstract: An object is to simplify a power supply noise analysis model of a circuit board. CAD data of the circuit board is obtained from a CAD apparatus, and overlapping power supply islands among power supply islands existing in different layers of the circuit board are extracted as a power supply pair. Nodes are arranged in the extracted power supply pair, and the nodes of the power supply pair are projected on the power supply islands to which the power supply pair belongs. A mesh region which encloses each node is determined for each power supply island, and impedance (L, R, C) between nodes is calculated. Then, a power supply noise analysis model is created based on the impedance between nodes in each layer, and a capacitance between layers.

Abstract: A power supply noise analysis model creation method comprising; obtaining a distance which appears most frequently, from among the distances from a vias judged to be the nearest to the vias, respectively, as a reference via pitch, generates four nodes for the via of target wherein the four nodes generates the middle point with the other four via that are near the via of the target, obtaining meshes which include the nodes, respectively, by dividing the power island structure and the power supply pair by dividing lines which pass between the generated nodes, and converting each of the meshes obtained to a circuit element equivalent to the mesh.

Abstract: An object is to simplify a power supply noise analysis model of a circuit board. CAD data of the circuit board is obtained from a CAD apparatus, and overlapping power supply islands among power supply islands existing in different layers of the circuit board are extracted as a power supply pair. Nodes are arranged in the extracted power supply pair, and the nodes of the power supply pair are projected on the power supply islands to which the power supply pair belongs. A mesh region which encloses each node is determined for each power supply island, and impedance (L, R, C) between nodes is calculated. Then, a power supply noise analysis model is created based on the impedance between nodes in each layer, and a capacitance between layers.