Abstract: Provided are techniques for capturing compression efficiency metrics for processing data. In response to retrieving native data for a first operation, perform the first operation; perform a second operation to generate a compression efficiency metric from the native data based on a ratio of the native data to compressed native data; and store the compression efficiency metric persistently for subsequent use in prioritizing compression of the native data.

Abstract: Provided are techniques for capturing compression efficiency metrics for processing data. In response to retrieving native data for a first operation, perform the first operation; perform a second operation to generate a compression efficiency metric from the native data based on a ratio of the native data to compressed native data; and store the compression efficiency metric persistently for subsequent use in prioritizing compression of the native data.

Abstract: Provided are techniques for capturing compression efficiency metrics for processing data. In response to retrieving native data for a first operation, perform the first operation; perform a second operation to generate a compression efficiency metric from the native data based on a ratio of the native data to compressed native data; and store the compression efficiency metric persistently for subsequent use in prioritizing compression of the native data.

Abstract: In one embodiment, a method includes moving data from an original, unmoved stride from an original array to target stripes of a target stride in a distributed array in response to a determination that all target stripes of the target stride are in a blank state indicating no data is stored therein, delaying movement of the data from the original stride to the target stripes of the target stride in response to a determination that any of the target stripes of the target stride are in an old state indicating unmoved data is stored therein, and moving the data from the original stride to the target stripes of the target stride after delaying and in response to a determination that all the target stripes of the target stride that were in the old state have switched to the blank state.

Abstract: In one embodiment, a method includes moving data from an original, unmoved stride from an original array to target stripes of a target stride in a distributed array in response to a determination that all target stripes of the target stride are in a blank state indicating no data is stored therein, delaying movement of the data from the original stride to the target stripes of the target stride in response to a determination that any of the target stripes of the target stride are in an old state indicating unmoved data is stored therein, and moving the data from the original stride to the target stripes of the target stride after delaying and in response to a determination that all the target stripes of the target stride that were in the old state have switched to the blank state.

Abstract: In one embodiment, a method includes iteratively selecting an original, unmoved stride from an original array until all original strides have been moved, determining a target stride location in a distributed array, determining a state of the target stride from the following states: an old state indicating unmoved data, a blank state indicating no data, and a new state indicating migrated data, determining that all target stripes are blank, moving data from the original stride to the target stripes when all the target stripes are blank, delaying the moving of the data from the original stride to the target stripes in the target stride when any of the target stripes of the target stride are in the old state and waiting until all the target stripes of the target stride are in the blank state, and determining that all original strides from the original array have been moved.

Abstract: Provided are techniques for capturing compression efficiency metrics for processing data. In response to retrieving native data for a first operation, perform the first operation; perform a second operation to generate a compression efficiency metric from the native data based on a ratio of the native data to compressed native data; and store the compression efficiency metric persistently for subsequent use in prioritizing compression of the native data.

Abstract: In one embodiment, a method includes iteratively selecting an original, unmoved stride from an original array until all original strides have been moved, determining a target stride location in a distributed array, determining a state of the target stride from the following states: an old state indicating unmoved data, a blank state indicating no data, and a new state indicating migrated data, determining that all target stripes are blank, moving data from the original stride to the target stripes when all the target stripes are blank, delaying the moving of the data from the original stride to the target stripes in the target stride when any of the target stripes of the target stride are in the old state and waiting until all the target stripes of the target stride are in the blank state, and determining that all original strides from the original array have been moved.

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 method and controller for implementing dynamic banding of a storage device, such as a Self Encrypting Device (SED) in a data storage array, and a design structure on which the subject controller circuit resides are provided. The controller dynamically identifies band boundaries for the storage device at the time a data storage array is created, when one or more devices are added into an existing data storage array, and when a replacement device is rebuilt into an exposed array, or an array with a failed device. A storage device band definition is provided based upon the dynamically identified band boundaries for the storage device.

Abstract: A method according to one embodiment includes defining a new encryption band with a length that is consistent with a redundant array of inexpensive disks (RAID) parity strip; freeing a working extent in a working stride on the RAID. In an iterative process until each stride in a source band is depleted of data: marking a source extent in a source stride from which to gather data to be re-encrypted; marking parity inconsistent in the working stride in the new encryption band; performing a second iterative process; and freeing the working extent. The second iterative process is performed until each extent in a source stride is depleted of data. Additional systems, methods and computer program products are also presented.

Abstract: A method and controller for implementing dynamic banding of a storage device, such as a Self Encrypting Device (SED) in a data storage array, and a design structure on which the subject controller circuit resides are provided. The controller dynamically identifies band boundaries for the storage device at the time a data storage array is created, when one or more devices are added into an existing data storage array, and when a replacement device is rebuilt into an exposed array, or an array with a failed device. A storage device band definition is provided based upon the dynamically identified band boundaries for the storage device.

Abstract: Provided are a method, system, and article of manufacture for error checking addressable blocks in storage. Addressable blocks of data are stored in a storage in stripes, wherein each stripe includes a plurality of data blocks for one of the addressable blocks and at least one checksum block including checksum data for the addressable block. A write request is received to modify data in one of the addressable blocks. The write and updating the checksum are performed in the stripe having the modified addressable block. An indication is made to perform an error checking operation on the stripe for the modified addressable block in response to the write request, wherein the error checking operation reads the data blocks and the checksum in the stripe to determine if the checksum data is accurate. An error handling operation is initiated in response to determining that the checksum data is not accurate.

Abstract: A method according to one embodiment includes defining a new encryption band with a length that is consistent with a redundant array of inexpensive disks (RAID) parity strip; freeing a working extent in a working stride on the RAID. In an iterative process until each stride in a source band is depleted of data: marking a source extent in a source stride from which to gather data to be re-encrypted; marking parity inconsistent in the working stride in the new encryption band; performing a second iterative process; and freeing the working extent. The second iterative process is performed until each extent in a source stride is depleted of data. Additional systems, methods and computer program products are also presented.

Abstract: A RAID system is provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: A RAID system is provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: Methods are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: Method, system and computer program product are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: Method, system and computer program product are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.

Abstract: Methods are provided for detecting and correcting dropped writes in a storage system. Data and a checksum are written to a storage device, such as a RAID array. The state of the data is classified as being in a “new data, unconfirmed” state. The state of written data is periodically checked, such as with a timer. If the data is in the “new data, unconfirmed” state, it is checked for a dropped write. If a dropped write has occurred, the state of the data is changed to a “single dropped write confirmed” state and the dropped write error is preferably corrected. If no dropped write is detected, the state is, changed to a “confirmed good” state. If the data was updated through a read-modified-write prior to being checked for a dropped write event, its state is changed to an “unquantifiable” state.