International Business Machines Corporation

Norman Apperley

James T Brady

Steven D Gerdt

Alden B Johnson

Stephen Peter Legg

Carlos Francisco Fuente

William James Scales

Ian David Judd

Patrick Allen Buckland

Matthew John Fairhurst

Vinay V Shah

David C Haigh

Richard Rolls

Roger J Edwards

Raymond L Foster

Peter Verey

Michael Haslam

An adapter for converting an interface of a data storage device is provided. The adapter has a first interface for connection to the interface of the data storage device and a second interface for connection to one or more host systems. The adapter includes a processor for converting commands and data between the first and second interfaces. The adapter transforms the data storage device to emulate physically and logically a higher availability and higher performance native data storage device. The adapter has a first connector compatible with the first interface for attachment to the data storage device and a second connector compatible with the second interface for attachment to the one or more host systems. The first and second connectors are disposed in the adapter in a back to back arrangement. The adapter logically separates commands for the data storage device from commands for the adapter.

Adapter, converted data storage device and method of operation of a converted data storage device

An adapter for converting an interface of a data storage device is provided. The adapter includes a first interface for connection to the interface of the data storage device and a second interface for connection to a plurality of host systems. The first interface may be an ATA or SCSI interface and the second interface may be a SSA or FC-AL interface suitable for attachment to multiple host systems. Conversion means are provided by the adapter for converting commands and data between the first and second interfaces. The adapter also has means for sorting commands and data to and from the plurality of host systems. The adapter acts as a single host system for the data storage device and includes means for retrieving error information from the data storage device in the event of a command terminating in an error. The adapter also comprises means for entering an error handling state with one of the plurality of host systems that persists until terminated by the host system and means for transferring the retrieved error information to the host system.

Adapter and method for handling errors in a data storage device converted to be accessible to multiple hosts

A method and system for reading data from a redundant array of computer data storage media elements without having to wait for a timeout in a drive in the redundant array. If the requested data is from a drive that is temporarily in a timeout, the requested data is reconstructed using other drives in the redundant array, and the reconstructed data is sent to the requester via an array controller. When the drive holding the originally requested data comes back from the timeout and responds to the original request by transmitting the original data, the array controller ignores the original data since the request has already been fulfilled by the reconstructed data.

Data storage array method and system

A spindle synchronization technique is described which is useful in a disk array subsystem comprising a plurality of disk drives (40,41,42,43) connected by means of serial links (25,26,27,28) to a disk drive controller (20). Data and command information is transmitted over the link in the form of multi-character frames, the flow of which is regulated by special ten bit protocol characters. A SYNC protocol character is defined which is used to synchronize the spindles of the disk drives. This SYNC character is issued by controller to selected ones of the drives over the same link used for the transmission of the command and data information. The SYNC character may be interleaved between the characters of frames being transmitted over the link.

Disk drive synchronization

Predictive failure analysis of a storage subsystem is efficiently conducted and data quickly recovered from a failed Read operation. This may be implemented in a storage system including a host coupled to a supervising processor that couples to a parity-equipped RAID storage subsystem having multiple HDAs each including an HDA controller and at least one storage medium. In one embodiment, when an HDA experiences an error during a Read attempt, the HDA transmits a recovery alert signal to the supervising processor; then, the processor and HDA begin remote and local recovery processes in parallel. The first process to complete provides the data to the host, and the second process is aborted. In another embodiment, an HDA's PFA operations are restricted to idle times of the HDA. A different embodiment limits HDA performance of PFA to times when the processor is conducting data reconstruction. Another embodiment monitors HDA errors at the supervisory processor level, initiating an HDA's PFA operations when errors at that HDA have a certain characteristic, such as a predetermined frequency of occurrence.

Efficient system for predicting and processing storage subsystem failure

Apparatus and method for transferring data in a data storage subsystems

A display management system for one or more large plasma gas panel displays (11) is organized to split the display management operations between a host processor (20), a system microprocessor (21) and a picoprocessor (27). The picoprocessor (27) is the heart of a common internal bus (31) plasma display adapter (22). The program for the display is downloaded from the host processor (20) to the system microprocessor (21). The microprocessor generates op codes and initializes display parameters. The plasma display adapter provides control for the plasma panel interface, serialization of character generator data, translates display position addresses for absolute cartesian coordinates to panel address, and computes the boundaries of display panel write and erase operations. Interaction between the system microprocessor and the plasma display adapter is minimized by a code list contained in the microprocessor memory and fetched by direct memory access. This code list contains high level commands which the picoprocessor in the adapter decodes and translates into simple commands for the surrounding interface logic.

Data management for plasma display

Growing community of inventors

Chandlers Ford, United Kingdom

Norman Apperley