Abstract:
A cache storage system and method are provided for saving storage space in a cache, the system and method for use in a data storage system having multiple storage devices and multiple vitual addresses, each virtual address having a data object associated therewith. Each data object is stored at a storage device location having a unique identifier. The cache storage system and method include a cache for storing a data object associated with at least one virtual address. For a first virtual address, the first virtual address data object is staged into the cache. For a second virtual address, a pointer is generated for use in pointing to the first virtual address data object staged in the cache when the storage device location identifier of the second virtual address data object matches the storage device location identifier of the first virtual address data object.
Abstract:
Apparatus and methods for reducing the sensitivity of spin valve sensor read heads for magnetic tape applications are provided. The apparatus and methods compromise the large output gain derived from using state of the art spin valve sensors in order to reduce the flux capture and thus, the signal distortion in the spin valve sensor. In order to provide a reduced sensitivity spin valve sensor, one or more of the basic sensitivity of the spin valve, the flux carrying capability of the free layer, and the flux injection efficiency of the spin valve head structure are modified to reduce the flux capture by the sensing layer.
Abstract:
A method and apparatus to handle multiple sets of removable media within a storage system. A first set of removable media are mounted on a set of drives. Data is accepted until the first set of removable media is filled. A second set of removable media is mounted on the drives, while the first set of removable media is removed. When the change is removable media is complete, writing of data proceeds on the second set of removable media. Data may be buffered while the change in removable media occurs. Alternatively, two sets of removable media may be mounted at the same time. When the first set of removable media is filled to a selected amount, the second set of removable media may then be used to write the data. A third set of removable media is set up or mounted for use, while the first set of removable media is removed.
Abstract:
A method and system for sharing robotic mechanisms (14) between physically remote storage libraries in an automated storage library system includes routing robotic mechanism guide structures (46,48) between the storage libaries. The guide structures run through robotic mechansim transfer ports located on the sides of the housing enclosures of the storage libraries. A robotic mechanism within an first storage library moves through the transfer port of the enclosure of the first storage library onto the guide structure. The robotic mechanism then moves out of the enclosure of the first storage library along the guide structure towards a second storage library. The robotic mechanism then moves along the guide structure through the transfer port of the enclosure of the second storage library and into the second storage library for performing operations such as accessing media objects within the second storage library.
Abstract:
A module (10) for a tape head assembly includes a first substrate (11) having active elements (18) and a second substrate (12) having active elements (20). The active elements on the first and second substrates can be read elements, write elements, or a combination of read and write elements. The second substrate is positioned over the first substrate. In one embodiment, the active elements of the first substrate are aligned between the active elements of the second substrate when the second substrate is positioned over the first substrate. In a second embodiment, the active elements of the first substrate are aligned directly across the active elements of the second substrate when the second substrate is positioned over the first substrate.
Abstract:
The invention transforms source data from a source platform to a target platform with a single copy. A data request signal is communicated from the target platform to the source platform and a location of the source data is determined in a disk subsystem supporting snapshot. The disk subsystem (i.e., a snapshot facility) copies the source data in raw form to one or more target disks designated by the target platform. The locations of the source data and the target disks are communicated to the target platform and the source data is read from the disk subsystem to transform the data to the target platform. The process starts from a request of an application resident within the target platform. One or more data management units can be used to determine source and target disk locations. Preferably, the source platform also communicates metadata to the target platform; and thus metadata, when available, is also copied via snapshot operations in the disk subsystem. The use of Snapshot creates a static copy to help ensure data integrity.
Abstract:
A tape cartridge and reel for storing magnetic tape wound on the reel such that damage to the edges of the magnetic tape is significantly reduced. A protective ring is formed in the reel or in the tape cartridge such that shock-induced energy is transmitted through a defined path. Transmission of the shock-induced energy through the defined path is effective to avoid the compression of the flanges of the reel so that the edges of the magnetic tape are not folded, wrinkled, or otherwise damaged.
Abstract:
The present invention provides a tape head (30) with reduced pole-tip recession. A recessed substrate (37) and a closure (32) of the tape head are separated by a plurality of layers, which include, for example, a bottom layer (35), a recessed bottom pole (86), a write gap (88), a shared pole (84), a read gap (60), a top pole (82) and a top layer (48). The recessed bottom pole is positioned in the recess of the substrate. By utilizing the recessed substrate and the recessed bottom pole, the thickness of the overcoat layer is reduced, thereby reducing the distance between the substrate and the closure at an air-bearing surface of the recording head. With the present invention, wear is reduced, thereby reducing pole tip recession.
Abstract:
A mechanism (151) for defining a write protect state of a data storage media (103) enclosed in a housing (101) of a data storage element (100) is disclosed. The mechanism (151) includes an aperture (302) formed in an exterior surface of the housing (101). A member (323) movable between a first and second region within the aperture (302). A first human intelligible mark (326) approximates the first region to depict a portion of a predetermined symbol corresponding to either a write enable or protect state. A second human intelligible mark (325) placed on the member (323) for depicting a remaining portion of the symbol. The second mark being alignable with the first mark (326) in the first region to depict the whole symbol, thereby indicating one of the states of the media. When the first and second marks (326, 325) are not aligned, they (326, 325) depict a portion of the symbol to indicate the remaining state of the media.
Abstract:
A method is described for managing data records stored in non-volatile memory in a disk drive system with cache memory. A variable-length directory containing descriptors of disk records is used to locate a selected record non-volatile memory. A table, ordered sequentially by record number, is used to quickly locate a record in non-volatile memory without having to perform a time-consuming search. In order to efficiently utilize space in non-volatile memory, a list is kept of free space for storing record descriptors. After an initial nominal allocation, additional free space is allocated only when required, thus further increasing the efficiency of use of non-volatile memory.