Abstract: A computer-implemented method, according to one embodiment, includes: detecting a first error while accessing a magnetic tape, determining a first error location on the magnetic tape where the first error occurred, determining one or more areas on the magnetic tape to be examined, independent of a read and/or write operation, inducing relative motion between a tape head and the magnetic tape such that the tape head is positioned adjacent to each of the respective one or more areas in turn, using the tape head to measure a number of servo errors that occur in each of the respective one or more areas, and identifying each of the one or more areas having a respective number of measured servo errors which exceeds a threshold value as a damaged area of the magnetic tape. The one or more areas are determined using a predetermined algorithm which incorporates the first error location.

Abstract: Aspects of the present disclosure relate to a method for timing index write to a tape medium of a tape system. Index write timing data that specifies index write timing based on file metadata attributes is stored. Metadata attributes of a first file are analyzed to determine whether a first index should be written at a first time based on the index write timing data. In response to determining that an index should be written, the first index is written to the tape medium at the first time.

Abstract: A multivolume management method, executed by a computer, includes storing a dataset over a plurality of media storage devices, wherein the plurality of media storage devices has a corresponding plurality of physical identifiers, generating a conversion table that assigns the plurality of physical identifiers to a corresponding plurality of sequentially ordered virtual identifiers, wherein each physical identifier is uniquely assigned to one virtual identifier, receiving a request for the dataset, wherein the request references the plurality of sequentially ordered virtual identifiers, in response to receiving the request, generating a response comprising an ordered list of physical identifiers using the conversion table, and responding to the request with the response. A computer system and computer program product corresponding to the above method are also disclosed herein.

Abstract: A system accesses metadata on a file system of the magnetic tape, where the metadata comprising one or more fields enabling to determine a longitudinal position (LPOS) of one or more files located on the magnetic tape. The system determines the LPOS of the one or more files located on the magnetic tape. The system determines an optimal location of the head on the magnetic tape based on computing an average value to the determined LPOS of the one or more files located on the magnetic tape and moves the head on the magnetic tape to the optimal location.

Abstract: According to an aspect of the present invention, there is a method, computer program product and/or system for storing data that performs the following operations (not necessarily in the following order): (i) receiving a request to migrate a data file from primary storage to secondary storage; (ii) invoking a primary data extraction function, registered by a user, to determine primary data for the data file; and (iii) inserting the primary data into a stub file.

Abstract: One or more processors receive data records from a file system, and convert the data records to a tape image having a format defined by the file system. The tape image is written to a first storage device, and a sequence of data types of the first storage device and a second storage device are monitored to determine whether the first storage device sequence of data types differs from the sequence of data types of the second storage device. Determining that the sequence of data types of the first storage device and second storage device do differ, one or more processors copying, to the second storage device, the data records from the first storage device, from the position on the first storage device that corresponds to the end-of-data position of the second storage device, to the end-of-data position of the first storage device.

Abstract: A system according to one embodiment includes a processor and logic integrated with and/or executable by the processor. The logic is configured to cause the processor to store hierarchically-organized global configuration information for each node and each tape library resource in a storage cluster to at least one memory accessible by each node of the storage cluster. The storage cluster includes at least one tape library. Also, the logic is configured to cause the processor to migrate data to and/or recall data from a tape cartridge pool within a tape library, using the hierarchically-organized global configuration information and via a node which has access to the tape cartridge pool, in response to receiving a migration and/or recall request at any node of the storage cluster. Other systems, methods, and computer program products for management of data and resources in a tiered data storage system are described in more embodiments.

Abstract: Linear Tape File System that can accommodate various storage orders, such as sequential and reverse sequential, on a tape medium. The storage order may be reversed (or otherwise changed) at the block level and also the bit order within the block level. The LFTS related data associated with the LFTS file system stores data sufficient to indicate storage order (for example, reverse), so that the motions of the tape medium and tape drive can be coordinated during reading or erasing operations to be performed in the correct order, with a view to the order the data was stored on the tape. Storing data in reverse order on an LFTS tape can lead to certain operational advantages.

Abstract: A mechanism is provided for providing information about fragmentation of a file on a sequential access medium by a computer system is disclosed. An actual time for reading the file recorded on the sequential access medium is estimated based on a physical position of the file. A total length of the file on the sequential access medium is calculated based on a physical length of each data piece constituting the file. An expected time for reading the file by assuming that the file is rewritten continuously is estimated based on the total length of the file. Information about the fragmentation of the file is then provided based on the actual time and the expected time.

Abstract: An apparatus, method, system, and program product are disclosed for tape copying. One method includes mounting a first source tape of multiple source tapes on a source tape drive. The method includes mounting a destination tape on a destination tape drive. The method also includes copying a first index of an index partition of the first source tape to a first copied index of an index partition of the destination tape. The method includes storing first position information corresponding to the first copied index on the destination tape. The method also includes copying first data of a data partition of the first source tape to a first copied data of a data partition of the destination tape. The method includes storing second position information corresponding to the first copied data on the destination tape.

Abstract: A method, executed by a computer, for recording data includes splitting a file into sequential extents, reordering the sequential extents into non-sequential extents, writing the non-sequential extents to a storage medium, writing dummy data to the storage medium, and writing extent placement information corresponding to a placement for the non-sequential extents to the storage medium. A computer program product and computer system corresponding to the above method are also disclosed herein.

Abstract: The time required for recalling the file is reduced when the file is written in a mounted plurality of tapes in comparison to recalling the file when written in a non-mounted plurality of tapes. In the non-mounted state, criteria does not typically exist in order to recall the written file within the plurality of tapes. Embodiments of the present invention provide systems and methods for recalling files based on criteria which considers: the mounted state of a tape; the type of tape; the type of available tape drive; the number of files included in a tape; and the location of the written file in a tape.

Abstract: The time required for recalling the file is reduced when the file is written in a mounted plurality of tapes in comparison to recalling the file when written in a non-mounted plurality of tapes. In the non-mounted state, criteria does not typically exist in order to recall the written file within the plurality of tapes. Embodiments of the present invention provide systems and methods for recalling files based on criteria which considers: the mounted state of a tape; the type of tape; the type of available tape drive; the number of files included in a tape; and the location of the written file in a tape.

Abstract: A capability to store meta-information related to file access histories on tape recording systems is provided. Base meta-information is stored on a tape. The base meta-information is meta-information that is associated with one or more files that are stored on the tape and is based, at least in part, on a tape access operation history. A first quantity of differentiated meta-information is stored on the tape at a predetermined time interval after storing the base meta-information, wherein the first quantity of differentiated meta-information is based, at least in part, on the tape access operation history and reflects a history of at least one file of the one or more files that are associated with the base meta-information.

Abstract: A method to identify data elements conforming to a policy includes receiving a request to identify data elements in an input set of data elements that conform to one or more requested policies. According to the method, policy output information describing data elements that conform to a requested policy are saved in association with the requested policy. In response to receiving a subsequent request to identify data elements in a subsequent set of data elements that conform to the requested policy, the method includes outputting the saved policy output information based on the policy output information having been saved in association with the requested policy. A computer program product and a system, configured with processors and a memory that can store saved policy information, can implement the method.

Abstract: An approach to reducing overhead to enable high-speed writing even when a large number of small-sized files are written onto a tape in a file system. The method of the present invention includes the steps of: writing multiple files consecutively onto a tape to become one combined file; writing, onto the tape, first index information including the start position and size of the combined file on the tape; and writing, onto the tape, second index information including the start position and size of each of the multiple files in the combined file on the tape.

Abstract: According to one embodiment, a method includes presenting a medium to more than one user as being exclusively occupied by whichever user attempts to access at least one file from the medium, writing a first file managed by a first user to a data partition of the medium, and storing a first user identifier (ID) that identifies the first user as metadata to an index partition of the medium in response to writing the first file managed by the first user. In another embodiment, a method includes reading metadata from an index partition of a medium from a first user of a plurality of users, extracting first file attribute information associated with a first user ID that indicates a first user from the metadata, and reading a first file based on the first file attribute information associated with the first user ID from a data partition of the medium.

Abstract: An apparatus, method, system, and program product are disclosed for tape copying. One method includes mounting a first source tape of multiple source tapes on a source tape drive. The method includes mounting a destination tape on a destination tape drive. The method also includes copying a first index of an index partition of the first source tape to a first copied index of an index partition of the destination tape. The method includes storing first position information corresponding to the first copied index on the destination tape. The method also includes copying first data of a data partition of the first source tape to a first copied data of a data partition of the destination tape. The method includes storing second position information corresponding to the first copied data on the destination tape.

Abstract: A request to open a file from a plurality of files in a storage is received from an application. The storage is made up of an index partition, containing recordings of file system indexes, and a data partition, containing recordings of the indexes and the file system data body. A file descriptor is created with an update flag that references the file. A determination is made that the file is being updated by the application, and the update flag is set to a value representing that the file is being updated. A request to write an index of the file system is received. A determination is made whether a specific file from the plurality of files is being updated. The index is written to the storage with an extended attribute for the specific file indicating that the specific file was being updated at the time the index was written.

Abstract: A request to open a file from a plurality of files in a storage is received from an application. The storage is made up of an index partition, containing recordings of file system indexes, and a data partition, containing recordings of the indexes and the file system data body. A file descriptor is created with an update flag that references the file. A determination is made that the file is being updated by the application, and the update flag is set to a value representing that the file is being updated. A request to write an index of the file system is received. A determination is made whether a specific file from the plurality of files is being updated. The index is written to the storage with an extended attribute for the specific file indicating that the specific file was being updated at the time the index was written.