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: 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 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: 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 method, executed by at least one processor, includes receiving a migration request for a plurality of files, assigning files of the plurality of files that are smaller than a selected size to one or more small-file secondary storage devices, assigning files of the plurality of files that are larger than the selected size to one or more large-file secondary storage devices, and initiating migration of the plurality of files from one or more primary storage devices to the secondary storage devices to which they are assigned. A corresponding computer program product and computer system are also disclosed herein.

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: 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 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: 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: 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: An information providing system and method, including a computer, for providing time taken to read a file, which includes an acquisition unit. The acquisition unit obtains information on a recording position of a file when the file is recorded in a storage device. A recording unit writes information on the obtained recording position to an index referred to access the file. A calculation unit calculates time taken to read the file using the information on the recording position written to the index in response to a request to obtain the time taken to read the file, and providing the calculated time to a requester that requests the time.

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: 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: 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 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: 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: 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: 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 method of a virtual tape server (VTS) for processing a mount request from a host system, the method comprising the steps of receiving a logical-volume (LVOL) mount request from the host system using a virtual-tape drive (VTD) of the virtual tape server; determining whether the logical volume is present in a virtual storage region (cache) using a controller in the virtual tape server; determining using the controller, if it is determined that the logical volume is not present in the virtual storage region, whether the mount request is a write request; and notifying, if it is determined that the mount request is a write request, the host system of completion of the mounting without reading the requested logical volume from a physical tape library that is externally connected to the virtual tape server into the virtual storage region.

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.