Fujitsu Corporation

Shigeyuki Maeda

Nina Tsukamoto

Nina Arataki

Tomoyuki Kanayama

Yumiko Nagasawa

A storage apparatus includes first and second controller modules. The first controller module monitors power states of the first and second controller modules. When the monitoring results indicate that the power state of the first controller module is an ON state and the power state of the second controller module is an ON processing state in which an ON process of switching from OFF to ON is being executed, the first controller module maintains the power state of the first controller module upon detection of a power control signal for controlling the power state of the first controller module.

Storage apparatus, controller module, and storage apparatus control method

In a storage device expandable through serially coupling two or more additional enclosures, each including a first additional controller and a second additional controller, to a controller enclosure, including a first controller and a second controller, a first route is formed by serially coupling the first controller of the controller enclosure to the first additional controllers of the additional enclosures in the order of adding the additional enclosures and a second route is formed by serially coupling the second controller of the controller enclosure to the second additional controllers of the additional enclosures in an order different from that of adding the additional enclosures.

Storage device and a method for expanding the same

A memory includes a set of sequentially stored data. Each of the data includes a variable-length data and length information indicative of a data length of the variable-length data. An MPU creates a read instruction for reading the set of data. A DMS chip, upon receiving the read instruction, reads length information from the memory, calculates a storage location of subsequent data in the memory, and reads the subsequent data from the first memory. Thus, the DMS chip reads the subsequent data from the memory instead of the MPU thereby reducing load on the MPU.

Method apparatus and computer programming product for direct memory access(DMA) technique on sequentially stored data

A semiconductor storage device has semiconductor memories each divided into a plurality of logical volumes, wherein host units connected to the semiconductor storage device perform read/write accesses to the logical volumes via access means, the semiconductor storage device further including: data shifting means which performs data shifting required when the constitution of the logical volume is modified, by using a memory block table provided for data shifting process and data shifting buffers provided in a stand-by memory, the data shifting being done in units of memory blocks within the logical volume which is subject to modification; and access control means for managing an access instruction table provided for access from the host units to the target addresses, and for allowing accesses from the host units to be performed properly while the data is being shifted.

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Kawasaki, Japan

Shigeyuki Maeda