Abstract: To improve performance of a storage system. The storage system includes a plurality of storage nodes that communicate via a network. Each of the plurality of storage nodes includes one or more controllers. At least one controller in the controllers specifies at least two controllers that allocate a cache sub-area where write data is stored based on a controller that receives the write data from a host and a controller that processes the write date, and the cache sub-area is allocated in the specified controllers.

Abstract: To improve performance of a storage system. The storage system includes a plurality of storage nodes that communicate via a network. Each of the plurality of storage nodes includes one or more controllers. At least one controller in the controllers specifies at least two controllers that allocate a cache sub-area where write data is stored based on a controller that receives the write data from a host and a controller that processes the write date, and the cache sub-area is allocated in the specified controllers.

Abstract: To improve performance of a storage system. The storage system includes a plurality of storage nodes that communicate via a network. Each of the plurality of storage nodes includes one or more controllers. At least one controller in the controllers specifies at least two controllers that allocate a cache sub-area where write data is stored based on a controller that receives the write data from a host and a controller that processes the write date, and the cache sub-area is allocated in the specified controllers.

Abstract: Provided is a storage system in which a plurality of storage controllers communicate with each other and an identifier of each storage controller is determined. The storage system includes a plurality of controllers that receive and process an input and output request specifying any of a plurality of volumes from an external device, and a plurality of switches each having a plurality of ports. The plurality of controllers are connected in parallel to the plurality of switches and communicate with each other via the plurality of switches. Each of the plurality of controllers acquires a plurality of port identifiers identifying a plurality of connected ports from the connected switches, and determines a controller identifier in the storage system based on the acquired plurality of port identifiers.

Abstract: To improve performance of a storage system. The storage system includes a plurality of storage nodes that communicate via a network. Each of the plurality of storage nodes includes one or more controllers. At least one controller in the controllers specifies at least two controllers that allocate a cache sub-area where write data is stored based on a controller that receives the write data from a host and a controller that processes the write date, and the cache sub-area is allocated in the specified controllers.

Abstract: Provided is a storage system in which a plurality of storage controllers communicate with each other and an identifier of each storage controller is determined. The storage system includes a plurality of controllers that receive and process an input and output request specifying any of a plurality of volumes from an external device, and a plurality of switches each having a plurality of ports. The plurality of controllers are connected in parallel to the plurality of switches and communicate with each other via the plurality of switches. Each of the plurality of controllers acquires a plurality of port identifiers identifying a plurality of connected ports from the connected switches, and determines a controller identifier in the storage system based on the acquired plurality of port identifiers.

Abstract: Provided is a storage system in which a plurality of storage controllers communicate with each other and an identifier of each storage controller is determined. The storage system includes a plurality of controllers that receive and process an input and output request specifying any of a plurality of volumes from an external device, and a plurality of switches each having a plurality of ports. The plurality of controllers are connected in parallel to the plurality of switches and communicate with each other via the plurality of switches. Each of the plurality of controllers acquires a plurality of port identifiers identifying a plurality of connected ports from the connected switches, and determines a controller identifier in the storage system based on the acquired plurality of port identifiers.

Abstract: When one of a plurality of storage apparatuses receives an input/output (IO) request in which the address of a logical volume is designated, a cache destination storage device in which I/O data conforming to the received I/O request is to be cached is determined on the basis of a target I/O pattern and/or a coupling mode. The I/O data is cached in the CM area of the cache destination storage device. The target I/O pattern is the one among a plurality of I/O patterns to which an I/O conforming to the received I/O request belongs. Each of the plurality of I/O patterns pertains to whether an I/O destination address in the logical volume is random or sequential. The coupling mode indicates whether or not a storage device that receives an I/O request in which the same address as that designated in the received I/O request is designated has been determined.

Abstract: When one of a plurality of storage apparatuses receives an input/output (IO) request in which the address of a logical volume is designated, a cache destination storage device in which I/O data conforming to the received I/O request is to be cached is determined on the basis of a target I/O pattern and/or a coupling mode. The I/O data is cached in the CM area of the cache destination storage device. The target I/O pattern is the one among a plurality of I/O patterns to which an I/O conforming to the received I/O request belongs. Each of the plurality of I/O patterns pertains to whether an I/O destination address in the logical volume is random or sequential. The coupling mode indicates whether or not a storage device that receives an I/O request in which the same address as that designated in the received I/O request is designated has been determined.

Abstract: An optical disk that enables a laser beam to be focused on an object track without making mistakes, an optical disk device, a format processing method, and a recording method. The optical disk shall be configured to has a guiding layer with a physical groove structure containing address information and a single or multiple recording layers with no groove structure, in which the guide areas for recording the address information thereon are formed along a track of the guide layer at fixed intervals in a user data area of each recording layer. An address for the recording layer is generated based on information obtained from the guide layer, and the address for the recording layer is recorded in the guide area.

Abstract: The invention provides an optical disc apparatus which prevents that a laser beam whose power is set at a read power level causes erroneous data recording or deletion. The optical disc apparatus includes an emission controller which controls an amount of an electrical current that a current supply portion supplies to a laser diode in order to control a level of emission power at which the laser diode emits the laser beam. The emission controller has a function to set levels of the emission power at the following transition processings: a transition processing after a read processing and before a write processing, a transition processing after a write processing and before a read processing, a transition processing between two read processings for respective areas, and a transition processing between two write processings for respective areas.

Abstract: The invention provides an optical disc apparatus which prevents that a laser beam whose power is set at a read power level causes erroneous data recording or deletion. The optical disc apparatus includes an emission controller which controls an amount of an electrical current that a current supply portion supplies to a laser diode in order to control a level of emission power at which the laser diode emits the laser beam. The emission controller has a function to set levels of the emission power at the following transition processings: a transition processing after a read processing and before a write processing, a transition processing after a write processing and before a read processing, a transition processing between two read processings for respective areas, and a transition processing between two write processings for respective areas.