Abstract: A communication device (101) transmits data by switching types of data to be transmitted by a unit of a time slot. A data transmission unit (6) transmits transmission data during a time slot corresponding to a type of the transmission data. Further, the data transmission unit (6) decides a retransmission time for performing a retransmission of the transmission data based on a time when a transmission of the transmission data has been completed.

Abstract: An apparatus, system, and method are disclosed for redundant write caching. The apparatus, system, and method are provided with a plurality of modules including a write request module, a first cache write module, a second cache write module, and a trim module. The write request module detects a write request to store data on a storage device. The first cache write module writes data of the write request to a first cache. The second cache write module writes the data to a second cache. The trim module trims the data from one of the first cache and the second cache in response to an indicator that the storage device stores the data. The data remains available in the other of the first cache and the second cache to service read requests.

Abstract: A method for reducing an amount of time required for performing consistency checking in a redundant storage system includes steps of: providing an information repository associated with each of a primary drive and at least one redundant drive; storing, in the information repository, information relating to input/output failures on the primary drive and redundant drive; determining a likelihood that one or more regions of the primary drive and/or redundant drive contains inconsistent data as a function of the information stored in the information repository; and performing consistency checking on the one or more regions of the primary drive and the redundant drive determined to have at least a prescribed likelihood of containing inconsistent data to thereby reduce the amount of time required for performing consistency checking.

Abstract: A Redundant Array of Independent Disks (RAID) system is disclosed in this invention. The RAID system includes a plurality of data storage units and a parity storage medium. The parity storage medium can be singular storage hardware or a logical storage module including multiple storage units. The parity storage medium cooperates with the data storage units to form a RAID. The parity storage medium is used for storing parity information of the RAID. A first write speed of the parity storage medium is faster than a second write speed of each data storage unit.

Abstract: The exemplary embodiments of this invention provide in one non-limiting aspect thereof a control device operable to execute a filter layer, and includes a first interface for coupling to a first storage device and a second interface for coupling to a second storage device. The filter layer receives communications and, in a first mode, synchronously transmits the communications to the first storage device and asynchronously transmits the communications to the second storage device, and, in a second mode, synchronously transmits the communications to the second storage device.

Abstract: Systems and methods are disclosed for storing the firmware and other data of a flash memory controller, such as using a RAID configuration across multiple flash memory devices or portions of a single memory device. In various embodiments, the firmware and other data used by a controller, and error correction information, such as parity information for RAID configuration, may be stored across multiple flash memory devices, multiple planes of a multi-plane flash memory device, or across multiple blocks or pages of a single flash memory device. The controller may detect the failure of a memory device or a portion thereof, and reconstruct the firmware and/or other data from the other memory devices or portions thereof.

Abstract: This disclosure describes methods, systems and software that can be used to calculate the estimated mean time to data loss for a particular configuration of a disk group. For example, a system can be used to evaluate a plurality of configurations, and/or to select (and/or allow a user to select) an optimal configuration of the disk group, based, in some cases, on the relative estimated mean times to data loss of the various configurations. This can allow, if desired, the configuration of the disk group to minimize the likelihood of data loss in the disk group.

Abstract: A simultaneous failure occurrence degree calculation section calculates a simultaneous failure occurrence degree a value of which becomes smaller with an increase in a difference between numeric values indicative of manufacture date information on a computer which performs a process on the basis of a duplication combination management program. A combination pattern generation section then combines two of a plurality of storage apparatus and generates a plurality of combination patterns. A simultaneous failure occurrence degree adding section then calculates a total of simultaneous failure occurrence degrees corresponding to combinations of storage apparatus for each of the plurality of combination patterns. A duplication combination pattern determination section then determines that a combination pattern for which the total of simultaneous failure occurrence degrees is the smallest is a duplication combination pattern.