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 memory that includes a data partition and an index partition is mounted. The data partition includes an original data and an original index written directly after the original data. The index partition includes the original index at the beginning of the index partition. The first data is written to a data partition of the memory. The first data is written directly after the at least one data on the data partition and the original index is deleted and invalidated. Responsive to a time interval elapsing, a first index is written to the data partition of the memory directly after the first data. The time interval starts at the writing of the first data. Responsive to the time interval elapsing, the first index is written to the index partition of the memory at the closest location, in terms of movement time, to the first index on the data partition.

Abstract: A method, a computer program product, and a computer system for backing up data in a backup storage space. A computer receives a request for backing up a second data file, wherein the second data file is created from a first data file. The computer determines whether a third data file satisfies one or more of predetermined conditions for backup; wherein the third data file is generated when the second data file is created from the first data file and the third data file comprises information for creating the second data file from the first data file. In response to determining that the third data file satisfies the one or more of the predetermined conditions for backup, the computer backs up the third data file, without backing up the second data file.

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: A memory that includes a data partition and an index partition is mounted. The data partition includes an original data and an original index written directly after the original data. The index partition includes the original index at the beginning of the index partition. The first data is written to a data partition of the memory. The first data is written directly after the at least one data on the data partition and the original index is deleted and invalidated. Responsive to a time interval elapsing, a first index is written to the data partition of the memory directly after the first data. The time interval starts at the writing of the first data. Responsive to the time interval elapsing, the first index is written to the index partition of the memory at the closest location, in terms of movement time, to the first index on the data partition.

Abstract: Managing a file on a tape. In response to a request to write a first file to a tape, whether a second file including data identical to the first file already exists on the tape is detected. If the second file exists, a first index of the second file is updated. After completing the write of the first file, metadata, including data starting position and size of the first file, is added to the first index. In response to a request to read the first or second files, the metadata of the first and second indexes are read. Based on the metadata, which of the first or second files can be accessed faster from a current head position is determined. The first file or the second file that can be accessed faster is then read from the 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: Managing a file on a tape. In response to a request to write a first file to a tape, whether a second file including data identical to the first file already exists on the tape is detected. If the second file exists, a first index of the second file is updated. After completing the write of the first file, metadata, including data starting position and size of the first file, is added to the first index. In response to a request to read the first or second files, the metadata of the first and second indexes are read. Based on the metadata, which of the first or second files can be accessed faster from a current head position is determined. The first file or the second file that can be accessed faster is then read from the tape.

Abstract: In an approach for writing data on a tape using a file system, a processor receives a first write request of a first file. A processor obtains data of the first file. A processor writes the data of the first file on a tape. A processor receives a second write request of a second file prior to completion of writing the data of the first file on the tape. A processor adds information about the second file to a first list, wherein the first list includes files waiting to write. Subsequent to writing the data of the first file on the tape, a processor obtains data of the second file based on the first list. A processor writes the data of the second file after the first file on the tape.

Abstract: A mechanism is provided for updating data of a file on a tape in a file system using a tape drive. Data of a file which received a write request is read out from a tape drive and stored in a memory. At least a part of the data of the file is edited and the edited data part of the file is stored in the memory. Combination data with a non-edited data part and the edited data part of the file is written on the tape in the tape drive as a continuous data of the file to have an extent. The extent of the written continuous data of the file is then written on the tape.

Abstract: A computer-implemented method for copying data from a source medium to a target medium in a storage system by a computer system, the storage system including a storage device, a first drive configured to access the source medium, and a second drive configured to access the target medium, the method comprising: estimating a waiting time for copy target data to be transferred from the source medium, selecting migration target data of the storage device based on whether migration of data to the target medium is expected to be finished within the waiting time or not, migrating the migration target data from the storage device to the target medium by the second drive while locating and/or reading the copy target data on the source medium by the first drive, and writing the copy target data to the target medium by the second drive.

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: In an approach for writing data on a tape using a file system, a processor receives a first write request of a first file. A processor obtains data of the first file. A processor writes the data of the first file on a tape. A processor receives a second write request of a second file prior to completion of writing the data of the first file on the tape. A processor adds information about the second file to a first list, wherein the first list includes files waiting to write. Subsequent to writing the data of the first file on the tape, a processor obtains data of the second file based on the first list. A processor writes the data of the second file after the first file on the tape.

Abstract: In an approach for writing data on a tape using a file system, a processor receives a first write request of a first file. A processor obtains data of the first file. A processor writes the data of the first file on a tape. A processor receives a second write request of a second file prior to completion of writing the data of the first file on the tape. A processor adds information about the second file to a first list, wherein the first list includes files waiting to write. Subsequent to writing the data of the first file on the tape, a processor obtains data of the second file based on the first list. A processor writes the data of the second file after the first file on the tape.

Abstract: In an approach for writing data on a tape using a file system, a processor receives a first write request of a first file. A processor obtains data of the first file. A processor writes the data of the first file on a tape. A processor receives a second write request of a second file prior to completion of writing the data of the first file on the tape. A processor adds information about the second file to a first list, wherein the first list includes files waiting to write. Subsequent to writing the data of the first file on the tape, a processor obtains data of the second file based on the first list. A processor writes the data of the second file after the first file on the tape.

Abstract: Managing a file on a tape. In response to a request to write a first file to a tape, whether a second file including data identical to the first file already exists on the tape is detected. If the second file exists, a first index of the second file is updated. After completing the write of the first file, metadata, including data starting position and size of the first file, is added to the first index. In response to a request to read the first or second files, the metadata of the first and second indexes are read. Based on the metadata, which of the first or second files can be accessed faster from a current head position is determined. The first file or the second file that can be accessed faster is then read from the tape.

Abstract: In an approach for writing data on a tape using a file system, a processor receives a first write request of a first file. A processor obtains data of the first file. A processor writes the data of the first file on a tape. A processor receives a second write request of a second file prior to completion of writing the data of the first file on the tape. A processor adds information about the second file to a first list, wherein the first list includes files waiting to write. Subsequent to writing the data of the first file on the tape, a processor obtains data of the second file based on the first list. A processor writes the data of the second file after the first file on the tape.

Abstract: In an approach to determining a storage to which to store a file in a storage system including at least one server and at least two storages which can communicate with the at least one server through a communication network, a computer obtains a file name of a file to be stored in a storage. The computer determines an effect of deduplication of data of the file based on the file name, and responsive to determining the effect of deduplication exists, selects a part of the file name. The computer then calculates a hash value using the part of the file name and determines a storage to which to store the file based on the hash value.