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: 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.

Abstract: A control apparatus connected to different types of storage devices include a performance-information storing section that stores performance information on the storage devices; a list storing section that stores a list of data on the storage devices; a monitoring section that monitors the load statuses of the storage devices and the control apparatus; a detecting section; an estimating section; and a determining section.

Abstract: A mechanism is provided for tape writing of small transactions. A first file is written as a plurality of fixed-length data sets (DS), the DS number of the final DS in the plurality of DS is stored in memory as #N(DS#N) and the WP number as #M(WP#M), and the final first file and the second file in the DS following the final DS(DS#N, WP#M) containing the first file are packed and written in sequential DS units, and are stored as DS#N, DS#N+1, etc, and WP#M+1 in sequential order in DS containing the second file. The remaining first, second, or third file is packed and DS#N with WP#M is overwritten as DS#N with WP#M+2, and the remaining #N in the DS numbers of the second file and the third file in the subsequent DS are written as DS#N+1, N+2, etc. with WP#M+2, and the DS#N, #N+1, #N+2, etc. with WP+M+2 are stored.

Abstract: In a controller of a tape drive, a CM input-output unit recognizes a tape format; a tape variable acquisition unit acquires tape variables; a setting variable acquisition unit acquires setting variables; and a minimum number calculator calculates a minimum number m of sub datasets, which are to be written to a tape to secure resistance to burst error, by using the tape variables and setting variables. When a command processor receives a synchronization command, the buffer manager generates n sub datasets for storing data in the buffer. If n is smaller than m, m sub datasets are padded out and set as write data. If n is m or more, the n sub datasets are set as write data. Then, the channel input-output unit writes the write data to the tape.

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.

Abstract: A data storage device for writing data. When data is written to tape, a predetermined length of tape is allocated on a first track for the data. The data is forward written on a first track and reverse written, in the same sequence, on a second track on the tape. If the data cannot be written on the predetermined length of tape, then a linking writer writes the data in a length unrestricted on the tape, and the predetermined length of tape is adjusted for the next data to be written to the tape.

Abstract: A control apparatus connected to different types of storage devices include a performance-information storing section that stores performance information on the storage devices; a list storing section that stores a list of data on the storage devices; a monitoring section that monitors the load statuses of the storage devices and the control apparatus; a detecting section; an estimating section; and a determining section.

Abstract: A storage area, among multiple storage areas, which meets a predetermined requirement is determined to be a target for access. In a controller for controlling a multi-tiered storage subsystem, the following components operate under the control of a file write unit and a file read unit. First, a list acquiring unit obtains a list of tiers that can meet file access requirements. A requisite energy calculating unit calculates an additional energy amount necessary to satisfy file access requirements for each tier, an allowable energy calculating unit calculates an allowable additional energy amount, and a path retrieving unit determines a path to a target tier based on the energy amounts. An identifier acquiring unit obtains a file identifier, and an access point generating unit determines a file access point based on the path and the file identifier. A method for controlling a multi-tiered storage subsystem is also described.

Abstract: A write/read control method for recording at least one datum on a magnetic tape within a predetermined distance is provided. The method includes sequentially accumulating a plurality of blocks of data of variable length in a buffer divided into fixed length segments and writing the contents of each segment to the tape. If the segment contains at least one block of data, the data is written to the tape as a dataset and if the segment does not contain any data, then a null dataset is written to the tape within the predetermined distance. The predetermined distance may vary depending upon the format of a tape drive embodying the method. In response to a request to read a block of data, reading at least one dataset that includes the requested block of data from the tape to segments in the buffer, and reading the requested block of data for invalidating data transfer of a null dataset in the segment. By invalidating the transfer of a null dataset, blocks of data separated by the null dataset can be reconstructed.

Abstract: A write/read control method for recording at least one datum on a magnetic tape within a predetermined distance is provided. The method includes sequentially accumulating a plurality of blocks of data of variable length in a buffer divided into fixed length segments and writing the contents of each segment to the tape. If the segment contains at least one block of data, the data is written to the tape as a dataset and if the segment does not contain any data, then a null dataset is written to the tape within the predetermined distance. The predetermined distance may vary depending upon the format of a tape drive embodying the method. In response to a request to read a block of data, reading at least one dataset that includes the requested block of data from the tape to segments in the buffer, and reading the requested block of data for invalidating data transfer of a null dataset in the segment. By invalidating the transfer of a null dataset, blocks of data separated by the null dataset can be reconstructed.

Abstract: Magnified and/or reduced areas of a display are easily determined by the shades of color and a pattern densities which correspond to the magnification or reduction ratio of areas of the display. The areas that have been magnified and/or reduced are presented by varying color intensity within areas reduced in size displayed with a deep hue in color to indicate that the area is compressed and a magnified area is displayed with a lighter color to indicate its expansion. Moreover, images of the display can be presented with a specification corresponding to each magnification or reduction ratio by linking the display with a movement of a pointing device, thus realizing a very easy-to-operate user interface.

Abstract: Backspacing over data to overwrite the data as recorded on magnetic tape is provided logically, rather than by causing a magnetic tape to drive to backhitch. The data is written to the magnetic tape as it was before it was logically changed in order to insure that the data is preserved on tape. Recovery of the data is from a succeeding data set which logically invalidates the original data by a superseding identifier. Control logic arranges data transactions for writing to magnetic tape as data sets; and, in response to backspace and overwrite commands, or when transactions are accumulated into a succeeding data set, rewrites the original transaction adjusted in accordance with the commands as a superseding data set downstream from the original transaction, logically invalidating the original transaction by setting a superseding identifier in the superseding data set(s).

Abstract: A data storage device for writing data. When data is written to tape, a predetermined length of tape is allocated on a first track for the data. The data is forward written on a first track and reverse written, in the same sequence, on a second track on the tape. If the data cannot be written on the predetermined length of tape, then a linking writer writes the data in a length unrestricted on the tape, and the predetermined length of tape is adjusted for the next data to be written to the tape.

Abstract: Magnified and/or reduced areas of a display are easily determined by the shades of color and a pattern densities which correspond to the magnification or reduction ratio of areas of the display. The areas that have been magnified and/or reduced are presented by varying color intensity within areas reduced in size displayed with a deep hue in color to indicate that the area is compressed and a magnified area is displayed with a lighter color to indicate its expansion. Moreover, images of the display can be presented with a specification corresponding to each magnification or reduction ratio by linking the display with a movement of a pointing device, thus realizing a very easy-to-operate user interface.