Abstract: Provided are techniques for task adjustment for uniform performance of drives. Arrays are created for different drive types. Performance benchmarks are run for each of the arrays to compute a stage maximum value and a destage maximum value for each of the drive types. At run time, in response to determining that a mode indictor indicates a uniform performance mode, a maximum number of stage Task Control Blocks (TCBs) are set to a stage maximum uniform value and a maximum number of destage TCBs are set to a destage maximum uniform value. The stage of first data is performed using an actual number of stage TCBs that do not exceed the maximum number of stage TCBs. The destage of second data is performed using an actual number of destage TCBs that do not exceed the maximum number of destage TCBs.

Abstract: Provided are techniques for task adjustment for uniform performance of drives. Arrays are created for different drive types. Performance benchmarks are run for each of the arrays to compute a stage maximum value and a destage maximum value for each of the drive types. At run time, in response to determining that a mode indictor indicates a uniform performance mode, a maximum number of stage Task Control Blocks (TCBs) are set to a stage maximum uniform value and a maximum number of destage TCBs are set to a destage maximum uniform value. The stage of first data is performed using an actual number of stage TCBs that do not exceed the maximum number of stage TCBs. The destage of second data is performed using an actual number of destage TCBs that do not exceed the maximum number of destage TCBs.

Abstract: Provided are a computer program product, system, and method for determining a storage device type on which to store extents of data in a storage system. The storage system provides a first storage device type that has native data compression at a first compression ratio and a second storage device type that has native data compression at a second compression ratio. The second compression ratio is higher than the first compression ratio. A determination is made for an extent to store the extent on the first storage device type or the second storage device type based on access frequency to data in the extent and an Input/Output (I/O) priority level for the extent. The extent is stored on the determined first or second storage device type.

Abstract: Provided are a computer program product, system, and method for determining to migrate data between compressed storage devices and non-compressed storage devices in a storage system. The storage system provides compressed storage devices having native data compression and a non-compressed storage devices not configured to have native compression. A determination is made of storage usage factors for the compressed storage devices and the non-compressed storage devices. A determination is made whether to move data between the compressed storage devices and the non-compressed storage devices based on the storage usage factors. Data is moved between the compressed storage devices and the non-compressed storage devices in response to determining to move the data between the compressed storage devices and the non-compressed storage devices.

Abstract: Provided are a computer program product, system, and method for using trap cache segments to detect malicious processes. A trap cache segment to the cache for data in the storage and indicated as a trap cache segment. Cache segments are added to the cache having data from the storage that are not indicated as trap cache segments. A memory function call from a process executing in the computer system reads data from a region of a memory device to output the read data to a buffer of the memory device. A determination is made as to whether the region of the memory device includes the trap cache segment. The memory function call is blocked and the process is treated as a potentially malicious process in response to determining that the region includes the trap cache segment.

Abstract: Provided are a computer program product, system, and method for using trap cache segments to detect malicious processes. A trap cache segment to the cache for data in the storage and indicated as a trap cache segment. Cache segments are added to the cache having data from the storage that are not indicated as trap cache segments. A memory function call from a process executing in the computer system reads data from a region of a memory device to output the read data to a buffer of the memory device. A determination is made as to whether the region of the memory device includes the trap cache segment. The memory function call is blocked and the process is treated as a potentially malicious process in response to determining that the region includes the trap cache segment.

Abstract: A computer-implemented method according to one embodiment includes identifying a request to migrate data associated with a volume from a first storage pool to a second storage pool; identifying entries in a first table corresponding to rank extents in the first storage pool containing the data; allocating and synchronizing a plurality of second tables for the identified entries of the first table that are located in the volume; transferring the data associated with the volume from the rank extents in the first storage pool containing the data to one or more rank extents in the one or more ranks of the second storage pool; and updating the second tables to correspond to the transferred data in the one or more rank extents in the one or more ranks of the second storage pool.

Abstract: Provided are a computer program product, system, and method for using trap cache segments to detect malicious processes. A trap cache segment to the cache for data in the storage and indicated as a trap cache segment. Cache segments are added to the cache having data from the storage that are not indicated as trap cache segments. A memory function call from a process executing in the computer system reads data from a region of a memory device to output the read data to a buffer of the memory device. A determination is made as to whether the region of the memory device includes the trap cache segment. The memory function call is blocked and the process is treated as a potentially malicious process in response to determining that the region includes the trap cache segment.

Abstract: A computer-implemented method according to one embodiment includes identifying a request to migrate data associated with a volume from a source storage pool having a first rank extent size to a destination storage pool having a second rank extent size smaller than the first rank extent size, creating a correspondence between logical volume extents of the volume and physical offset locations within rank extents of the source storage pool, and migrating data from one or more ranks of the source storage pool to one or more ranks of the destination storage pool, utilizing the correspondence between the logical volume extents of the volume and the physical offset locations within the rank extents of the source storage pool.

Abstract: A computer-implemented method according to one embodiment includes identifying a request to migrate data associated with a volume from a first storage pool to a second storage pool; identifying entries in a first table corresponding to rank extents in the first storage pool containing the data; allocating and synchronizing a plurality of second tables for the identified entries of the first table that are located in the volume; transferring the data associated with the volume from the rank extents in the first storage pool containing the data to one or more rank extents in the one or more ranks of the second storage pool; and updating the second tables to correspond to the transferred data in the one or more rank extents in the one or more ranks of the second storage pool.

Abstract: A method for improving destage performance to a RAID array is disclosed. In one embodiment, such a method periodically scans a cache for first strides that are ready to be destaged to a RAID array. While scanning the cache, the method identifies second strides that are not currently ready to be destaged to the RAID array, but will likely be ready to be destaged during a subsequent scan of the cache. The method initiates preemptive staging of any missing data of the second strides from the RAID array into the cache in preparation for the subsequent scan. Upon occurrence of the subsequent scan, the method destages, from the cache, the second strides from the cache to the RAID array. A corresponding system and computer program product are also disclosed.

Abstract: A method for reducing incidents of data loss in redundant arrays of independent disks (RAIDs) having the same RAID level is disclosed. In one embodiment, such a method identifies, in a data storage environment, a set of RAIDs having a common RAID level. The method also identifies, in the set of RAIDs, higher risk storage drives having a failure risk above a threshold and lower risk storage drives having a failure risk below the threshold. The method swaps, within the RAIDs, higher risk storage drives with lower risk storage drives to more evenly distribute higher risk storage drives across the RAIDs. A corresponding system and computer program product are also disclosed.

Abstract: A method according to one embodiment includes identifying a request to migrate data associated with a volume from a source storage pool to a destination storage pool, identifying volume segment table (VST) entries corresponding to rank extents within the source storage pool containing the data, allocating and synchronizing small VSTs for the identified VST entries within the volume, allocating one or more rank extents within the destination storage pool, transferring the data associated with the volume from the rank extents within the source storage pool containing the data to the one or more rank extents in the one or more ranks of the destination storage pool, updating the small VSTs to correspond to the transferred data in the one or more rank extents in the one or more ranks of the destination storage pool, and freeing the data from the one or more rank extents within the source storage pool.

Abstract: Provided are a computer program product, system, and method for a computer program product, system, and method for determining an availability score based on available resources of different resource types in a distributed computing environment of storage servers to determine whether to perform a failure operation for one of the storage servers. A health status monitor program deployed in the storage servers performs: maintaining information indicating availability of a plurality of storage server resources for a plurality of resource types; calculating an availability score as a function of a number of available resources of the resource types; and transmitting information on the availability score to a management program. The management program uses the transmitted information to determine whether to migrate services from the storage server from which the availability score is received to at least one of the other storage servers in the distributed computing environment.

Abstract: Provided are a computer program product, system, and method for reducing a rate at which data is mirrored from a primary server to a secondary server. A determination is made as to whether a processor utilization at a processor managing access to the secondary storage exceeds a utilization threshold. If so, a determination is made as to whether a specified operation at the processor is in progress. A message is sent to the primary server to cause the primary server to reduce a rate at which data is mirrored from the primary server to the secondary server in response to determining that the specified operation is in progress.

Abstract: Provided are a computer program product, system, and method for determining an optimum number of threads to make available per core in a multi-core processor complex to execute tasks. A determination is made of a first processing measurement based on threads executing on the cores of the processor chip, wherein each core includes circuitry to independently execute a plurality of threads. A determination is made of a number of threads to execute on the cores based on the first processing measurement. A determination is made of a second processing measurement based on the threads executing on the cores of the processor chip. A determination is made of an adjustment to the determined number of threads to execute based on the second processing measurement resulting in an adjusted number of threads. The adjusted number of threads on the cores is utilized to execute instructions.

Abstract: Provided are a computer program product, system, and method for using at least one machine learning module to select a priority queue from which to process an Input/Output (I/O) request. Input I/O statistics are provided on processing of I/O requests at the queues to at least one machine learning module. Output is received from the at least one machine learning module for each of the queues. The output for each queue indicates a likelihood that selection of an I/O request from the queue will maintain desired response time ratios between the queues. The received output for each of the queues is used to select a queue of the queues. An I/O request from the selected queue is processed.

Abstract: A computer-implemented method, according to one approach, is for converting an existing storage pool into an intended storage pool in place. The computer-implemented method includes: reordering volume extents in the existing storage pool such that physical rank extents of the volumes align with boundaries between rank extents of the intended storage pool. The ranks in the existing storage pool are also converted from first rank extent sizes to second rank extent sizes. Moreover, in response to converting the ranks in the existing storage pool, for each of the volumes: a temporary pause/lock is performed on a volume segment table (VST) entry which corresponds to the given volume, and the VST entry is populated with a new structure which corresponds to the respective second rank extent size.

Abstract: Provided are a computer program product, system, and method for fixing anomalies in a preserved data structure used to generate a temporary data structure during system initialization. A preserved data structure in persistent storage is used to build a temporary data structure in a memory of the computing system during initialization of the computing system. The temporary data structure represents computational resources in the computing system and is rebuilt from the preserved data structure during the initialization. The preserved data structure and the temporary data structure are processed to determine whether the preserved data structure includes at least one anomaly that would result in rebuilding the temporary data structure with an error. Information on the preserved data structure and the temporary data structure having the anomaly are processed to determine modifications to correct the preserved data structure. The determined modifications are processed to correct the preserved data structure.

Abstract: A storage controller is configured to perform a full stride destage, a strip destage, and an individual track destage. A machine learning module receives a plurality of inputs corresponding to a plurality of factors that affect performance of data transfer operations and preservation of drive life in the storage controller. In response to receiving the inputs, the machine learning module generates a first output, a second output, and a third output that indicate a preference measure for the full stride destage, the strip destage, and the individual track destage respectively.