Abstract: A data storage subsystem having a plurality of data compression engines configured to compress data, each having a different compression algorithm. A data handling system is configured to determine a present rate of access to data; select at least one sample of data; determine the greatest degree of compression of said data compression engines; determine the compression ratios of the operated data compression engines with respect to the selected sample(s); compressing said selected at least one sample with a plurality of said data compression engines at said selected tier; operate a selected data compression engines with respect to the selected sample and determine the greatest degree of compression of the data compression engines; compress the data from which the sample was selected with one of the operated data compression engines determined to have the greatest degree of compression; and store the compressed data in data storage repositories.

Abstract: A data storage subsystem having a plurality of data compression engines configured to compress data, each having a different compression algorithm. A data handling system is configured to determine a present rate of access to data; select at least one sample of data; determine the greatest degree of compression of said data compression engines; determine the compression ratios of the operated data compression engines with respect to the selected sample(s); compressing said selected at least one sample with a plurality of said data compression engines at said selected tier; operate a selected data compression engines with respect to the selected sample and determine the greatest degree of compression of the data compression engines; compress the data from which the sample was selected with one of the operated data compression engines determined to have the greatest degree of compression; and store the compressed data in data storage repositories.

Abstract: A data storage subsystem having a plurality of data compression engines configured to compress data, each having a different compression algorithm. A data handling system is configured to determine a present rate of access to data; select at least one sample of data; determine the greatest degree of compression of said data compression engines; determine the compression ratios of the operated data compression engines with respect to the selected sample(s); compressing said selected at least one sample with a plurality of said data compression engines at said selected tier; operate a selected data compression engines with respect to the selected sample and determine the greatest degree of compression of the data compression engines; compress the data from which the sample was selected with one of the operated data compression engines determined to have the greatest degree of compression; and store the compressed data in data storage repositories.

Abstract: Exemplary embodiments of the present invention disclose a method and system for reducing a probability of generating an unrecoverable error on a disk array during a disk rebuild. In a step, an exemplary embodiment identifies a disk to be replaced in the disk array, the disk array including a spare disk. In another step, an exemplary embodiment locates a region in the disk array that incurs a high number of reads and writes during a period prior to replacing the disk in the disk array. In another step, an exemplary embodiment scrubs data in a region in the disk array that has incurred a high number of accesses. In another step, an exemplary embodiment replaces the disk identified to be replaced with the spare disk in the disk array. In another step, an exemplary embodiment rebuilds data on the replaced disk on the spare disk in the disk array.

Abstract: A data storage subsystem having a plurality of data compression engines configured to compress data, each having a different compression algorithm. A data handling system is configured to determine a present rate of access to data; select at least one sample of data; determine the greatest degree of compression of said data compression engines; determine the compression ratios of the operated data compression engines with respect to the selected sample(s); compressing said selected at least one sample with a plurality of said data compression engines at said selected tier; operate a selected data compression engines with respect to the selected sample and determine the greatest degree of compression of the data compression engines; compress the data from which the sample was selected with one of the operated data compression engines determined to have the greatest degree of compression; and store the compressed data in data storage repositories.

Abstract: In one embodiment, pursuant to migrating the data from the first to the second storage medium, the data is allocated to the second storage medium while retaining an allocation of the data in the first storage medium. If the data is migrated from the second storage medium back to the first storage medium, the data is pointed to the allocation of the data in the first storage medium to alleviate data movement from the second storage medium to the first storage medium. If the allocation of the data in the first storage medium is determined to be needed for other data, the allocation of the data in the first storage medium is freed.

Abstract: In one embodiment, pursuant to migrating the data from the first to the second storage medium, the data is allocated to the second storage medium while retaining an allocation of the data in the first storage medium. If the data is migrated from the second storage medium back to the first storage medium, the data is pointed to the allocation of the data in the first storage medium to alleviate data movement from the second storage medium to the first storage medium. If the allocation of the data in the first storage medium is determined to be needed for other data, the allocation of the data in the first storage medium is freed.

Abstract: A method for more effectively distributing the I/O workload in a data replication system is disclosed herein. In selected embodiments, such a method may include generating an I/O request and identifying a storage resource group associated with the I/O request. In the event the I/O request is associated with a first storage resource group, the I/O request may be directed to a first storage device and a copy of the I/O request may be mirrored from the first storage device to a second storage device. Alternatively, in the event the I/O request is associated with a second storage resource group, the I/O request may be directed to a second storage device and a copy of the I/O request may be mirrored from the second storage device to the first storage device.

Abstract: In one embodiment, pursuant to migrating the data from the first to the second storage medium, the data is allocated to the second storage medium while retaining an allocation of the data in the first storage medium. If the data is migrated from the second storage medium back to the first storage medium, the data is pointed to the allocation of the data in the first storage medium to alleviate data movement from the second storage medium to the first storage medium. If the allocation of the data in the first storage medium is determined to be needed for other data, the allocation of the data in the first storage medium is freed.

Abstract: A method for managing extents in a data storage system includes monitoring usage statistics for an extent residing on one or more powered-up storage devices. In the event the extent has not been accessed for specified period of time (as determined from the usage statistics), the method automatically compresses the extent and migrates the extent to an intermediate repository. Once the amount of data in the intermediate repository reaches a specified level, the method migrates the extent from the intermediate repository to one or more normally powered-down storage devices. If I/O is received for the extent while it resides in the normally powered-down storage devices or the intermediate repository, the method automatically migrates the extent from the normally powered-down storage devices or the intermediate repository to the normally powered-up storage devices. A corresponding apparatus and computer program product are also disclosed.

Abstract: A method for managing extents in a data storage system includes monitoring usage statistics for an extent residing on one or more powered-up storage devices. In the event the extent has not been accessed for specified period of time (as determined from the usage statistics), the method automatically compresses the extent and migrates the extent to an intermediate repository. Once the amount of data in the intermediate repository reaches a specified level, the method migrates the extent from the intermediate repository to one or more normally powered-down storage devices. If I/O is received for the extent while it resides in the normally powered-down storage devices or the intermediate repository, the method automatically migrates the extent from the normally powered-down storage devices or the intermediate repository to the normally powered-up storage devices. A corresponding apparatus and computer program product are also disclosed.

Abstract: Exemplary method, system, and computer program embodiments for data migration between first and second storage mediums of an available plurality of storage mediums in a computing storage environment are provided. In one embodiment, pursuant to migrating the data from the first to the second storage medium, the data is allocated to the second storage medium while retaining an allocation of the data in the first storage medium. If the data is migrated from the second storage medium back to the first storage medium, the data is pointed to the allocation of the data in the first storage medium to alleviate data movement from the second storage medium to the first storage medium. If the allocation of the data in the first storage medium is determined to be needed for other data, the allocation of the data in the first storage medium is freed.

Abstract: A method for more effectively distributing the I/O workload in a data replication system is disclosed herein. In selected embodiments, such a method may include generating an I/O request and identifying a storage resource group associated with the I/O request. In the event the I/O request is associated with a first storage resource group, the I/O request may be directed to a first storage device and a copy of the I/O request may be mirrored from the first storage device to a second storage device. Alternatively, in the event the I/O request is associated with a second storage resource group, the I/O request may be directed to a second storage device and a copy of the I/O request may be mirrored from the second storage device to the first storage device. A corresponding system, apparatus, and computer program product are also disclosed and claimed herein.

Abstract: A data storage subsystem having a plurality of data compression engines configured to compress data, each having a different compression algorithm. A data handling system is configured to select at least one sample of data; operate a plurality of the data compression engines to compress the selected sample(s); determine the compression ratios of the operated data compression engines with respect to the selected sample(s); and select the data compression engine having the greatest compression ratio with respect to the selected sample(s), to compress the data. Further, the data compression engines may be in tiers from low to high in accordance with expected latency to compress data and to uncompress compressed data; and a data compression engine is selected from a tier that is inverse to the present rate of access.

Abstract: A system for analyzing mutually exclusive conflicts among a plurality of redundant devices in a computer system includes a data management module operable on the computer system. The data management module parses through status data generated by the plurality of redundant devices to identify an error condition in one of the plurality of redundant devices, generate metadata describing the error condition, and take action to resolve the error condition. A method of analyzing mutually exclusive conflicts among redundant devices in a computer system includes collecting status data from the redundant devices, identifying an error condition, generating metadata describing the condition, analyzing the metadata to determine a lowest-level or least impacting redundant device that is the root cause of the condition, and taking an action to resolve the condition.