Abstract: Communicating data with a medium is provided. A cache is provided for storing target data of a file identified by an access request from an application of a host. The cache is divided into a read cache, a write cache, and an index cache. Responsive to receiving the access request: the medium is loaded onto a drive using a file system; target data is stored to the write cache and to the read cache; and the index file stored in the index cache is updated to reflect position metadata about the target data stored in the write cache. Responsive to initiating unloading of the medium from the drive: the updated index file stored in the index cache is written to the index partition of the medium; and the target data stored in the write cache is written onto a data partition of the medium without using the file system.

Abstract: A storage system includes a plurality of tape drives connected to a host, and a buffer configured to temporarily hold data read from the drives. A mechanism loads a plurality of media on which a file has been written to the plurality of drives so as to mount the plurality of media in the plurality of drives and divides the file into a plurality of data portions in an order. The mechanism determines a medium that takes the shortest time to move from a current position of a read head of a corresponding drive to a beginning position of the file and one or more media from which following data portions of the beginning data portion are to be read. The mechanism executes reading of the following data portions from the next media and temporarily holding of the read following data portions in the buffer of the storage system while reading the beginning data portion of the file from the first medium to the host.

Abstract: Data is recorded such that the positions of data will be aligned in a traveling direction and a width direction of the storage medium. The medium travels in the traveling direction from a first to a second position as a certain wrap of a group of plural files in a first physical range between the first and the second positions. A head shifts from the certain wrap to another wrap in the width direction of the medium. The medium travels in the traveling direction from a third to a fourth position as the other wrap of a group of plural files in a second physical range between the third and the fourth positions. The plural files in groups on the certain wrap and the other wrap may be written in reverse order to each other after being once stored in a buffer.

Abstract: Data is recorded such that the positions of data will be aligned in a traveling direction and a width direction of the storage medium. The medium travels in the traveling direction from a first to a second position as a certain wrap of a group of plural files in a first physical range between the first and the second positions. A head shifts from the certain wrap to another wrap in the width direction of the medium. The medium travels in the traveling direction from a third to a fourth position as the other wrap of a group of plural files in a second physical range between the third and the fourth positions. The plural files in groups on the certain wrap and the other wrap may be written in reverse order to each other after being once stored in a buffer.

Abstract: A mechanism is provided for improved file synchronization of a magnetic tape. A destination device determines whether one or more file checksums exist in an extended file attribute associated with an identified file. Responsive to one or more file checksums existing in the extended file attribute associated with the identified file, the destination device reads the one or more file checksums out of the extended file attribute without accessing the magnetic tape. The destination device transmits the one or more file checksums to a source device. The source device segments the data of the new file into fixed-length blocks that do not overlap one another. The source device calculates one or more new file checksums for each of the fixed-length blocks. The source device transmits the one or more new file checksums to the destination device.

Abstract: In a controller of a tape drive, when an error recovery section cannot recover an error detected by an error detecting section, an error-report generation section generates an error report, an error-information acquisition section acquires error information of the tape drive and a cartridge loaded in the tape drive, an error-information exchange section acquires pieces of error information of other tape drives and cartridges loaded in these other tape drives, an error-factor judging section judges whether the error is attributable to the tape drive or the cartridge based on these pieces of error information, an error-report update section updates the error report in accordance with the result of this judgment, and an error-report output section outputs the error report thus updated to a host.

Abstract: A device for reading data recorded on a recording medium having multiple tracks, the device including: a receiver that receives designations of a number of data elements to be read; and a determination unit that determines an order of reading the data elements so that, no matter on which track of the tracks each of the data elements is recorded, the data elements are read in an order of recorded locations of the data elements in a direction along the tracks on which the data elements are recorded.

Abstract: A storage system includes a plurality of tape drives connected to a host, and a buffer configured to temporarily hold data read from the drives. A mechanism loads a plurality of media on which a file has been written to the plurality of drives so as to mount the plurality of media in the plurality of drives and divides the file into a plurality of data portions in an order. The mechanism determines a medium that takes the shortest time to move from a current position of a read head of a corresponding drive to a beginning position of the file and one or more media from which following data portions of the beginning data portion are to be read. The mechanism executes reading of the following data portions from the next media and temporarily holding of the read following data portions in the buffer of the storage system while reading the beginning data portion of the file from the first medium to the host.

Abstract: Data is recorded such that the positions of data will be aligned in a traveling direction and a width direction of the storage medium. The medium travels in the traveling direction from a first to a second position as a certain wrap of a group of plural files in a first physical range between the first and the second positions. A head shifts from the certain wrap to another wrap in the width direction of the medium. The medium travels in the traveling direction from a third to a fourth position as the other wrap of a group of plural files in a second physical range between the third and the fourth positions. The plural files in groups on the certain wrap and the other wrap may be written in reverse order to each other after being once stored in a buffer.

Abstract: Data is recorded such that the positions of data will be aligned in a traveling direction and a width direction of the storage medium. The medium travels in the traveling direction from a first to a second position as a certain wrap of a group of plural files in a first physical range between the first and the second positions. A head shifts from the certain wrap to another wrap in the width direction of the medium. The medium travels in the traveling direction from a third to a fourth position as the other wrap of a group of plural files in a second physical range between the third and the fourth positions. The plural files in groups on the certain wrap and the other wrap may be written in reverse order to each other after being once stored in a buffer.

Abstract: The mechanism provides for updating a file written on a medium in a system including a tape drive connected to a host. The mechanism receives, from the host, a change data part that is changed in the file as an update target. The mechanism writes the change data part to a data end position on the medium including a non-change data part that is not changed in the file sequentially stored on the medium. The mechanism calculates seek time required for positioning of a head of the tape drive from a medium position of the non-change data to a medium position of the change data part. The mechanism copies the change data part to an external storage device when the seek time is more than or equal to a predetermined value.

Abstract: In a controller of a tape drive, when an error recovery section cannot recover an error detected by an error detecting section, an error-report generation section generates an error report, an error-information acquisition section acquires error information of the tape drive and a cartridge loaded in the tape drive, an error-information exchange section acquires pieces of error information of other tape drives and cartridges loaded in these other tape drives, an error-factor judging section judges whether the error is attributable to the tape drive or the cartridge based on these pieces of error information, an error-report update section updates the error report in accordance with the result of this judgment, and an error-report output section outputs the error report thus updated to a host.

Abstract: A storage system includes a plurality of tape drives connected, to a host, and a buffer configured to temporarily hold data read from the drives. A mechanism loads a plurality of media on which a file has been written to the plurality of drives so as to mount the plurality of media in the plurality of drives and divides the file into a plurality of data portions in an order. The mechanism determines a medium that takes the shortest time to move from a current position of a read head of a corresponding drive to a beginning position of the file and one or more media from which following data portions of the beginning data portion are to be read. The mechanism executes reading of the following data portions from the next media and temporarily holding of the read following data portions in the buffer of the storage system while reading the beginning data portion of the file from the first medium to the host.

Abstract: A file system to controls access to a tape library that selectively loads and unloads a plurality of cartridges from a plurality of slots to a drive for transmitting to the file system archived data retrieved from a particular cartridge. The file system includes a cache and receives a request from a requestor to access the tape library, estimates a first data transfer rate from an anticipated tape library operation completion duration and from a capacity of cached data to be transmitted from the cache to the requestor, initiates access to the tape library, and adapts the first data transfer rate to a second data transfer rate to transmit the capacity of the cached data to the requestor throughout the anticipated tape library operation completion duration.

Abstract: A copy-source tape storage medium is prepared and includes a index partition for storing updated file metadata and associated metadata indexes and a data partition (DP) for storing valid data and associated valid data indexes and for storing invalid data that has changed or has been deleted or has been invalidated by the update and for storing associated invalid data indexes. Metadata indexes are retrieved and analyzed and a valid record number list indicating a range of record numbers of valid data is created. Records are read from the DP and data in records corresponding to record numbers not included on the valid record number list is replaced with meaningless data which is written to a copy-destination tape storage medium. Records corresponding to record numbers included on the valid record number list are copied to the copy-destination tape storage medium without alteration.

Abstract: Provided is a method for recording data to a tape medium in such a manner as to achieve the easy management of mutually related multiple data pieces. First data and second data continuously received as a file from a higher level apparatus are accumulated in multiple buffer segments in the form of multiple successive data sets. A data structure is determined for each of the accumulated data sets. Management information indicating a result of the determination is added to the data sets, and the data sets and the management information thereof are stored into the tape medium.

Abstract: According to one embodiment, a method for a plurality of users to write at least one file to a medium in such a manner that the file is divisionally managed in a system environment in which an input/output control is performed on a storage system includes saving, in the medium as metadata, a user identifier (ID) for identifying a user and file attribute information about the file managed by a user associated with the user ID, and writing, as data, the file managed by the user to the medium as indicated by the file attribute information. In other embodiments, a writing program product, a reading program product, and a system are presented that allow a plurality of users to write at least one file to a medium in such a manner that the file is divisionally managed in a system environment.

Abstract: According to one embodiment, a method for writing a file to a plurality of media includes loading a parent medium into a first drive to retrieve ID information about the parent medium from metadata, writing a first file part to the parent medium and, at about a same time, saving a file name, attribute information, and attribute information about the first file part to the parent medium as metadata, loading a child medium into a second drive in order to write subsequent file parts and retrieving ID information about the child medium from metadata, writing the subsequent file parts to the child medium and, at about a same time, saving the ID information and attribute information about the subsequent file parts to the parent medium, and additionally saving the ID information about the child medium and the attribute information about the subsequent file parts as metadata in the child medium.

Abstract: In a controller of a tape drive, when a command processing unit receives a Write FM0 command, a channel input/output unit writes the data in the buffer and a speculative FM onto the tape, and a CM input/output unit records speculative FM presence information in a cartridge memory. When the command processing unit receives Write FM1 command next, the CM input/output unit erases the speculative FM presence information from the cartridge memory. When the command processing unit receives a command other than Write FM1 command next, the channel input/output unit overwrites a speculative FM.

Abstract: Provided is a tape recorder that has a tape including at least one partition and that controls access to the tape. The tape recorder includes: means for identifying a position of data on the tape; means for sequentially reading necessary data areas in the data; means for sequentially copying the necessary data areas to the beginning of an empty area on the tape; means for creating a continuous front empty area formed of unnecessary data areas and copy source areas of the necessary data areas on the tape; and means for moving a beginning of the partition (BOP) to a position immediately after the front empty area and for updating the position information on the beginning of the partition.