Data is relocated, based on an intelligent data placement algorithm, from a first storage location to a second storage location in a disk storage system. A data placement record is generated including a virtual disk location associated with the data, the second storage location, and a first sequence value. The first sequence value indicates relative sequence when compared to other sequence values. The data placement record is written to a first record location on a first tape cartridge loaded in a tape drive. The data placement records are used with data records to restore data to disk storage from tape backup.

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.

In a general embodiment, a method includes storing 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 comprising at least one tape library. The method further includes migrating and/or recalling, using the hierarchically-organized global configuration information, data to and/or from a tape cartridge pool within a tape library. The migration or recall is performed by an appropriate node of the storage cluster and in response to receiving a migration or recall request at an arbitrary node of the storage cluster.

A computer system for migrating data in a computer storage system. Data is selected to migrate from a first storage to the second storage, wherein selected files are in a resident state. Metadata is obtaining and subsets of data are ordered based on the obtained metadata, the order of the subsets of data following an expectation of update value. The subsets of data are transferring to the second storage based on the order of the subsets of data based on a predetermined schedule. Data determined as inactive is overwritten on the sequential access medium by transferred data. End data to the sequential access medium is set after a last active data is written before the one or more sets of data are determined to be inactive. The one or more sets of data determined to be inactive are deleted from the second storage and a transfer is initiated.

A computer program product for migrating data in a computer storage system. Data is selected to migrate from a first storage to the second storage, wherein selected files are in a resident state. Metadata is obtaining and subsets of data are ordered based on the obtained metadata, the order of the subsets of data following an expectation of update value. The subsets of data are transferring to the second storage based on the order of the subsets of data based on a predetermined schedule. Data determined as inactive is overwritten on the sequential access medium by transferred data. End data to the sequential access medium is set after a last active data is written before the one or more sets of data are determined to be inactive. The one or more sets of data determined to be inactive are deleted from the second storage and a transfer is initiated.

A method and system for migrating data in a storage system by a computer system. The storage system includes a first storage and a second storage with a sequential access medium. The computer system selects a plurality of data to migrate from the first storage to the second storage. The computer system then obtains metadata information of each data and orders the plurality of the data based on the metadata information. The order of the data follows an expectation of update of the data. The computer system transfers the plurality of the data to the second storage based on the order of the data. The computer system determines whether data written in a rear region of the sequential access medium is inactive. The computer system overwrites the data determined to be inactive on the sequential access medium by transferred data.

A method for dynamically changing a buffer threshold in a tape drive, according to another embodiment, includes monitoring a history of sizes of data transactions between sync commands, the data transactions being from a host to a tape drive, determining that a next sync command is expected to be received relatively sooner or relatively later based on the history of data size transactions, writing buffered data to a magnetic recording tape in response to determining that the next sync command will be received relatively sooner, and increasing a buffer threshold for delaying writing to the magnetic recording tape in response to determining that the next sync command will be received relatively later. A computer program product according to one embodiment includes a computer readable storage medium having program code embodied therewith, the program code readable/executable by a processor to perform the foregoing method.

A tape drive system that uses (and/or includes) 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.

In one embodiment, a system includes a disk cache that includes a plurality of hard disk drives (HDDs) and a controller. The controller is configured to create one or more tape-managed partitions in the disk cache, each of the one or more tape-managed partitions being configured to store data that is subject to hierarchical storage management (HSM). The controller is also configured to create a premigration queue configured to service premigration data for all of the one or more tape-managed partitions. Moreover, the controller is configured to receive a premigration delay value for a first tape-managed partition, the premigration delay value defining a time period that elapses prior to queuing the premigration data for the first tape-managed partition to the premigration queue. The premigration delay value is based on a volume creation time. Other systems, methods, and computer program products are described in accordance with more embodiments.

A method and system for migrating data in a storage system by a computer system. The storage system includes a first storage and a second storage with a sequential access medium. The computer system selects a plurality of data to migrate from the first storage to the second storage. The computer system then obtains metadata information of each data and orders the plurality of the data based on the metadata information. The order of the data follows an expectation of update of the data. The computer system transfers the plurality of the data to the second storage based on the order of the data. The computer system determines whether data written in a rear region of the sequential access medium is inactive. The computer system overwrites the data determined to be inactive on the sequential access medium by transferred data.