A computer-implemented method, according to one embodiment, includes: sending one or more instructions to calculate a combined size of fragments included in the fragmented files, sending one or more instructions to designate a portion of cache which corresponds to at least the combined size of the fragments, sending one or more instructions to send a copy of each non-fragmented file from a first drive directly to a second drive in which the second sequential storage medium is loaded, sending one or more instructions to use the designated portion of the cache to accumulate the fragments included in the fragmented files, and sending one or more instructions to send a copy of each of the fragments corresponding to a given fragmented file from the cache to the second drive in response to determining that all of the fragments corresponding to the given fragmented file have been accumulated in the cache.

The direction of a WRAP and the logical points on which a file are written influence the efficiency of a recall of the file. Embodiments of the present invention provide methods and systems which can be applied to an upper storage layer and a lower storage layer in a hierarchical storage system. In turn, the migration and recall of a plurality of files, which contain data, are more rapid and efficient by preferring one logical point over another logical point.

A computer-implemented method includes identifying a source data object of a distributed computing environment. The distributed computing environment includes two or more storage nodes. The source data object exists as two or more slices. At least one of the slices is replicated on at least two storage nodes. The computer-implemented method further includes associating the source data object with a tape. The tape is written by a tape drive controlled from the distributed computing environment. The computer-implemented method further includes copying the source data object to the tape by, for each source slice of the two or more slices, in sequence: selecting a source node of the two or more storage nodes whereon the source slice is replicated, mounting the tape drive to the source node, appending the source slice to the tape, and unmounting the tape drive. A corresponding computer program product and computer system are also disclosed.

A computer-implemented method includes identifying a source data object of a distributed computing environment. The distributed computing environment includes two or more storage nodes. The source data object exists as two or more slices. At least one of the slices is replicated on at least two storage nodes. The computer-implemented method further includes associating the source data object with a tape. The tape is written by a tape drive controlled from the distributed computing environment. The computer-implemented method further includes copying the source data object to the tape by, for each source slice of the two or more slices, in sequence: selecting a source node of the two or more storage nodes whereon the source slice is replicated, mounting the tape drive to the source node, appending the source slice to the tape, and unmounting the tape drive.

An apparatus, method, system, and program product are disclosed for Tape positioning. One method includes identifying a first position on a first tape between a start of the first tape and an end of the first tape. The method includes determining that an access position of the first tape reaches the first position. The method also includes providing an indication indicating that the access position of the first tape has reached the first position.

A tape drive system that uses a tape cartridge having more than one file storage partition, sometimes herein referred to as virtual tapes. The tape file sub-system (which controls tape addressing) is identical to conventional single file storage partition tape cartridges, because: (i) a tape control sub-system controls writing of the multiple virtual tapes on a single tape cartridge, but communicates with the tape file sub-system as if the multiple virtual tapes were actually located on different physical tape cartridges; and (ii) a tape control sub-system controls reading of the multiple virtual tapes from a single tape cartridge, but communicates with the tape file sub-system as if the multiple virtual tapes were actually located on different physical tape cartridges. The multiple virtual tapes stored on a single physical tape cartridge are useful because they help circumvent certain per tape restrictions that are inherent in the tape file sub-system.

A dynamic premigration protocol is implemented in response to a secondary tier returning to an operational state and an amount of data associated with a premigration queue of a primary tier exceeding a first threshold. The dynamic premigration protocol can comprise at least a temporary premigration throttling level. An original premigration protocol is implemented in response to an amount of data associated with the premigration queue decreasing below the first threshold.

A dynamic premigration protocol is implemented in response to a secondary tier returning to an operational state and an amount of data associated with a premigration queue of a primary tier exceeding a first threshold. The dynamic premigration protocol can comprise at least a temporary premigration throttling level. An original premigration protocol is implemented in response to an amount of data associated with the premigration queue decreasing below the first threshold.

A tape drive that can select one or more wraps from any available wraps on a tape medium for writing temporary data upon detecting a flush condition. The one or more wraps selected for writing temporary data can be selected from wraps otherwise reserved for normal writing operations. Selection of the one or more wraps for temporary writing may be based on multiple considerations, including proximity to the wrap of current data writing operations and tape medium degradation. The one or more wraps selected for writing temporary data may be selected with or without regard of their assigned read/write direction. Assigning wraps based on proximity and/or degradation can lead to certain operational advantages including reducing tape write head movement in the transverse direction and spreading tape medium wear more evenly across the surface of the tape medium.

A tape drive that can select one or more wraps from any available wraps on a tape medium for writing temporary data upon detecting a flush condition. The one or more wraps selected for writing temporary data can be selected from wraps otherwise reserved for normal writing operations. Selection of the one or more wraps for temporary writing may be based on multiple considerations, including proximity to the wrap of current data writing operations and tape medium degradation. The one or more wraps selected for writing temporary data may be selected with or without regard of their assigned read/write direction. Assigning wraps based on proximity and/or degradation can lead to certain operational advantages including reducing tape write head movement in the transverse direction and spreading tape medium wear more evenly across the surface of the tape medium.