Abstract: A system and method for preventing inefficient recalls in a hierarchical storage management (HSM) system are presented. Difference data may be received for updating a target file stored in a first storage system having at least an upper storage layer and a lower tape layer. The difference data may be stored in a stub file located on the upper storage layer and corresponding to the target file in the first storage system located on the lower tape layer. A recall operation may be executed that copies the target file from the lower tape layer to the upper storage layer. The difference data stored in the stub file may be copied to the target file copied onto the upper storage layer from the lower tape layer according to one or more predetermined events.

Abstract: A system and method for preventing inefficient recalls in a hierarchical storage management (HSM) system are presented. Difference data may be received for updating a target file stored in a first storage system having at least an upper storage layer and a lower tape layer. The difference data may be stored in a stub file located on the upper storage layer and corresponding to the target file in the first storage system located on the lower tape layer. A recall operation may be executed that copies the target file from the lower tape layer to the upper storage layer. The difference data stored in the stub file may be copied to the target file copied onto the upper storage layer from the lower tape layer according to one or more predetermined events.

Abstract: A system for managing a plurality of storage devices that are configured to store a database. The system includes an access instruction acquiring unit configured for acquiring an access instruction to access the database. The system also includes a predicting unit configured for predicting a table to be accessed in response to the acquired access instruction. The system further includes a relocation unit configured for mirroring the table predicted by the predicting unit, the mirroring between the plurality of storage devices.

Abstract: An approach for dynamically changing a copy policy associated with a cluster grid for tape storage virtualization which involves monitoring one or more statuses of a plurality of clusters associated with the cluster grid, wherein the one or more of the plurality of clusters are assigned one of a plurality of copy modes, detecting that at least one of the plurality of clusters, having a highest priority copy mode associated with the cluster grid, is unavailable, selecting an available second cluster of the plurality of clusters and changing the copy policy wherein the available second cluster is assigned the highest priority copy mode.

Abstract: In one embodiment, a computer program product for dynamic volume mounting includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the circuitry to perform a method including receiving, from a host, a command directed to a volume. The command includes a parameter. A policy associated with the host is evaluated. Based on the evaluation, a value of the parameter included in the command is determined. In response to the parameter including a first value, two copies of the volume are opened. The parameter is set to include the first value when the one of the two copies of the volume is already open, and the two copies of the volume are opened in response thereto. In response to the parameter including a second value, only one of the two copies of the volume are opened.

Abstract: In a storage system including plural source storage devices, a target storage device selects which source storage device to accept a copy request from the target storage device so as to minimize the load on the entire system. The system calculates first and second load values for job loads being processed. System load values for the system are derived from job load value of a specific data, and respective load values for first and second source storage devices. The system compares the system load values to select a storage device to provide the data copy so as to minimize the load on the entire system.

Abstract: In one embodiment, a computer program product for disaster recovery (DR) testing includes a computer readable storage device having program code embodied therewith. The program code is readable and/or executable by a hardware processor to define a DR family including one or more DR clusters accessible to a DR host and one or more production clusters accessible to a production host, create a backup copy of data stored to the one or more production clusters, store the backup copy to the one or more DR clusters, establish a time-zero in the DR family, create a snapshot of each backup copy stored to the one or more DR clusters, share a point-in-time data consistency at the time-zero among all clusters within the DR family and perform DR testing. The DR host is configured to replicate data from the one or more production clusters to the one or more DR clusters.

Abstract: A computer-implemented method for storing data in a storage area, includes: storing a first data unit in a first area of the storage area, in response to a request to store a first data unit having a first attribute in the storage area, when at least one data unit having the first attribute is stored in the first area; and generating, a second area by reducing the first area, when no data unit having the second attribute is stored in the storage area in response to a request to store a second data unit having a second attribute in the storage area; furthermore, storing the second data unit in the second area.

Abstract: 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.

Abstract: In a storage system including plural source storage devices, a target storage device selects which source storage device to accept a copy request from the target storage device so as to minimize the load on the entire system. The system calculates first and second load values for job loads being processed. System load values for the system are derived from job load value of a specific data, and respective load values for first and second source storage devices. The system compares the system load values to select a storage device to provide the data copy so as to minimize the load on the entire system.

Abstract: In one embodiment, a computer program product for dynamic volume mounting includes a computer readable storage medium having program instructions embodied therewith. The program instructions are executable by a processing circuit to cause the circuitry to perform a method including receiving, from a host, a command directed to a volume. The command includes a parameter. A policy associated with the host is evaluated. Based on the evaluation, a value of the parameter included in the command is determined. In response to the parameter including a first value, two copies of the volume are opened. The parameter is set to include the first value when the one of the two copies of the volume is already open, and the two copies of the volume are opened in response thereto. In response to the parameter including a second value, only one of the two copies of the volume are opened.

Abstract: A computer-implemented method for storing data in a storage area, includes: storing a first data unit in a first area of the storage area, in response to a request to store a first data unit having a first attribute in the storage area, when at least one data unit having the first attribute is stored in the first area; and generating, a second area by reducing the first area, when no data unit having the second attribute is stored in the storage area in response to a request to store a second data unit having a second attribute in the storage area; furthermore, storing the second data unit in the second area.

Abstract: In one embodiment, a system includes a processor and logic configured to create a backup copy of data stored to one or more production clusters and store the backup copy to one or more disaster recovery (DR) clusters. Moreover, the logic is configured to establish a time-zero in the DR family and create a snapshot of each backup copy stored to the one or more DR clusters. Each snapshot represents data stored to the one or more DR clusters at the time-zero, and each snapshot is a point-in-time flash copy of at least a user data portion of all virtual tapes of the one or more DR clusters with the proviso that the snapshot does not include a metadata portion of the virtual tapes. The logic is further configured to share a point-in-time data consistency at the time-zero among all clusters within the DR family.

Abstract: In a storage system including plural source storage devices, a target storage device selects which source storage device to accept a copy request from the target storage device so as to minimize the load on the entire system. The system calculates first and second load values for job loads being processed. System load values for the system are derived from job load value of a specific data, and respective load values for first and second source storage devices. The system compares the system load values to select a storage device to provide the data copy so as to minimize the load on the entire system.

Abstract: In one embodiment, an apparatus comprises a processor and logic integrated with and/or executable by the processor, the logic being configured to cause the processor to receive, from a host, a command directed to a volume, the command including a parameter. The logic is further configured to cause the processor to evaluate a policy associated with the host, and, based on the evaluation of the policy associated with the host, determine a value of the parameter included in the command. Still yet, the logic is configured to cause the processor to open two copies of the volume in response to the parameter including a first value, and open only one of the two copies of the volume in response to the parameter including a second value.

Abstract: An approach for dynamically changing a copy policy associated with a cluster grid for tape storage virtualization which involves monitoring one or more statuses of a plurality of clusters associated with the cluster grid, wherein the one or more of the plurality of clusters are assigned one of a plurality of copy modes, detecting that at least one of the plurality of clusters, having a highest priority copy mode associated with the cluster grid, is unavailable, selecting an available second cluster of the plurality of clusters and changing the copy policy wherein the available second cluster is assigned the highest priority copy mode.

Abstract: A computer-implemented method for storing data in a storage area, includes: storing a first data unit in a first area of the storage area, in response to a request to store a first data unit having a first attribute in the storage area, when at least one data unit having the first attribute is stored in the first area; and generating, a second area by reducing the first area, when no data unit having the second attribute is stored in the storage area in response to a request to store a second data unit having a second attribute in the storage area; furthermore, storing the second data unit in the second area.

Abstract: In one embodiment, a method is provided for copying data in a virtual sequential access volume (VSAV) among at least two computers. The method of the present invention includes the operations of: writing first data in a first VSAV, into a first storage device of a first computer; updating version information on the first VSAV, and storing the updated version information and information on a write start position of the first data, into the first storage device; transmitting the information on the write start position of the first data to a second computer; writing the first data into a second storage device of the second computer, from the write start position of the first data; and updating version information on the first VSAV, and storing the updated version information and the received information on the write start position of the first data, into the second storage device.

Abstract: A method can include transmitting a first data from a first adapter to a buffer of a channel adapter device driver at a buffer memory transfer rate. The channel adapter device driver also receives a second data at a first port of the first adapter from a host at a first time. The method also includes determining a second time to send a device end status to the host, the device end status closes a channel from the host to the first adapter. The method also includes sending the device end status to the host at the second time through the first port. The method also includes transferring the second data from the first adapter to the buffer of the channel adapter device driver.

Abstract: 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.