Abstract: For data processing in a computing storage environment by a processor device, the computing storage environment incorporating at least high-speed and lower-speed caches, and managed tiered levels of storage, a Solid State Device (SSD) tier is variably shared between the lower-speed cache and the managed tiered levels of storage such that the managed tiered levels of storage are operational on large data segments, and the lower-speed cache is allocated with the large data segments, yet operates with data segments of a smaller size than the large data segments and within the large data segments, where if selected data segments are cached in the lower-speed cache and are determined to become uniformly hot, the selected group from the lower-speed cache are migrated to the SSD tier.

Abstract: A controller receives a request to perform a release space operation. A determination is made that a new discard scan has to be performed on a cache, in response to the received request to perform the release space operation. A determination is made as to how many task control blocks are to be allocated to the perform the new discard scan, based on how many task control blocks have already been allocated for performing one or more discard scans that are already in progress.

Abstract: For efficient track destage in secondary storage in a more effective manner, for temporal bits employed with sequential bits for controlling the timing for destaging the track in a primary storage, if a first bit has at least one of a lower amount of holes and a hotter data heat metric, it is moved to the lower speed cache level. If the first bit has a hotter data heat and greater than a predetermined number of holes, the first bit is discarded.

Abstract: A mechanism is provided in a data processing system for accessing a solid state drive. Responsive to receiving request to write an update to a block of data in the solid state drive with an update option set, the mechanism reads the block of data from the solid state drive. The mechanism determines a difference between the update and the block of data. The mechanism compresses the difference to form an update record. The mechanism stores the update record and modifies metadata of the block of data to reference the update record.

Abstract: For data processing in a computing storage environment by a processor device, the computing storage environment incorporating at least high-speed and lower-speed caches, and tiered levels of storage, groups of data segments are migrated between the tiered levels of storage such that if a selected group is cached in the lower-speed cache and is determined to become uniformly hot, migrating the selected group from the lower-speed cache to the SSD portion while refraining from processing data retained in the lower-speed cache until the selected group is fully migrated to the SSD portion.

Abstract: Various embodiments for cache management in a distributed computing storage environment are provided. In one embodiment, a processor device, for a plurality of input/output (I/O) operations, initiates a process, separate from a process responsible for data segment assembly, for waking a predetermined number of waiting I/O operations.

Abstract: For cache/data management in a computing storage environment, incoming data segments into a Non Volatile Storage (NVS) device of the computing storage environment are validated against a bitmap to determine if the incoming data segments are currently in use. Those of the incoming data segments determined to be currently in use are designated to the computing storage environment to protect data integrity.

Abstract: Storage tracks from at least one host are destaged from the write cache rank when it is determined that the at least one host is idle with respect to a first set of ranks, and storage tracks are refrained from being destaged from each rank when it is determined that the at least one host is not idle with respect to a second set of ranks.

Abstract: In a distributed server storage environment, a set of like tasks to be performed is organized into a first group, and a last used processing group associated with the like tasks is stored. Upon a subsequent dispatch, the last used processing group is compared to other processing groups and the tasks are assigned to a processing group based upon a predetermined threshold.

Abstract: A computational device maintains a first type of cache and a second type of cache. The computational device receives a command from the host to release space. The computational device synchronously discards tracks from the first type of cache, and asynchronously discards tracks from the second type of cache.

Abstract: A controller receives a request to perform staging or destaging operations with respect to an area of a cache. A determination is made as to whether more than a threshold number of discard scans are waiting to be performed. The controller avoids satisfying the request to perform the staging or the destaging operations or a read hit with respect to the area of the cache, in response to determining that more than the threshold number of discard scans are waiting to be performed.

Abstract: A set of like tasks to be performed is organized into a first group, and a last used processing group associated with the like tasks is stored. Upon a subsequent dispatch, the last used processing group is compared to other processing groups and the tasks are assigned to a processing group based upon a predetermined threshold.

Abstract: A disk drive receives a request to write at least one block of a first block size, wherein the disk drive is configured to store blocks of a second block size that is larger in size than the first block size. The disk drive stores a plurality of emulated blocks of the first block size in each block of the second block size. The disk drive generates a read error, in response to reading a selected block of the second block size in which the at least block of the first block size is to be written via an emulation. The disk drive performs a destructive write of selected emulated blocks of the first block size that caused the read error to be generated. The disk drive writes the at least one block of the first block size in the selected block of the second block size.

Abstract: A first data structure stores indications of storage locations that need to be copied for forming a consistency group. A second data structure stores indications of new host writes subsequent to starting a point in time copy operation to form the consistency group. Read access is secured to a metadata storage area and a determination is made as to whether the second data structure indicates that there are any new host writes. In response to determining that the second data structure indicates that there are new host writes, write access is secured to the metadata storage area, the first data structure is updated with contents of the second data structure to determine which additional storage locations need to be copied for formation of a next consistency group, and the second data structure is updated to indicate that that the second data structure is in an initialized state.

Abstract: A mechanism is provided in a data processing system. The mechanism determines a maximum queue depth of a queue for each solid state drive in a plurality of solid state drives. A given data block is mirrored between a group of solid state drives within the plurality of solid state drives. The mechanism tracks outstanding input/output operations in a queue for each of the plurality of solid state drives. For a given read operation to read the given data block, the mechanism identifies a solid state drive within the group of solid state drives based on a number of empty slots in the queue of each solid state drive within the group of solid state drives.

Abstract: A first data structure stores indications of storage locations that need to be copied for forming a consistency group. A second data structure stores indications of new host writes subsequent to starting a point in time copy operation to form the consistency group. Read access is secured to a metadata storage area and a determination is made as to whether the second data structure indicates that there are any new host writes. In response to determining that the second data structure indicates that there are new host writes, write access is secured to the metadata storage area, the first data structure is updated with contents of the second data structure to determine which additional storage locations need to be copied for formation of a next consistency group, and the second data structure is updated to indicate that that the second data structure is in an initialized state.

Abstract: Tracks are selected for destaging from a least recently used (LRU) list and the selected tracks are moved to a destaging wait list. The selected tracks are grouped and destaged from the destaging wait list.

Abstract: For data processing in a computing storage environment by a processor device, the computing storage environment incorporating at least high-speed and lower-speed caches, and tiered levels of storage, and at a time in which at least one data segment is to be migrated from one level to another level of the tiered levels of storage, a data migration mechanism is initiated by copying data resident in the lower-speed cache corresponding to the at least one data segment to be migrated to a target on the another level, reading remaining data, not previously copied from the lower-speed cache, from a source on the one level, and writing the remaining data to the target, and subsequent to the reading and the writing of the remaining data, destaging updates corresponding to the at least one data segment from either the higher and lower speed caches to the target.

Abstract: For data processing in a computing storage environment by a processor device, the computing storage environment incorporating at least high-speed and lower-speed caches, and tiered levels of storage, and at a time in which at least one data segment is to be migrated from one level to another level of the tiered levels of storage, a data migration mechanism is initiated by copying data resident in the lower-speed cache corresponding to the at least one data segment to be migrated to a target on the another level, reading remaining data, not previously copied from the lower-speed cache, from a source on the one level, and writing the remaining data to the target, and subsequent to the reading and the writing of the remaining data, destaging updates corresponding to the at least one data segment from either the higher and lower speed caches to the target.

Abstract: A processor, operable in a computing storage environment, for each rank in a storage management device in the computing storage environment, allocates a lower maximum count, and a higher maximum count, of Task Control Blocks (TCBs) to be implemented for performing a storage operation, and performs the storage operation using up to the lower maximum count of TCBs, yet only allows those TCBs above the lower maximum count to be allocated for performing the storage operation satisfying at least one criterion.