Abstract: In certain techniques, a plurality of storage devices of a storage system are sorted into a sequence of storage devices by capacity. A first number of at least one storage device with maximum capacity in the sequence of storage devices is determined. A group of storage devices are selected from the sequence of storage devices based on the first number, a device number of storage devices in the sequence and a threshold device number, the number of storage devices in the group of storage devices being less than or equal to the threshold device number. A user storage system is built based on storage space in the group of storage devices, the user storage system having a predetermined width for representing a sum of a data width and a parity width in one stripe of the user storage system. Accordingly, efficiency of storage space utilization can be improved.

Abstract: A storage system comprises stripes, extents comprised in one stripe among the stripes residing on storage devices in the storage system, respectively. A failed stripe is determined among the stripes, the failed stripe comprising a group of failed extents residing on a group of failed storage devices, respectively, a number of failed storage devices in the group being less than or equal to parity width of the storage system. Distribution of the group of failed extents in the failed stripe is obtained. A rebuild parameter for rebuilding data in the failed stripe is generated based on the obtained distribution. The generated rebuild parameter is stored for rebuilding the storage system. Accordingly, a rebuild parameter generated for one failed stripe is reused for other failed stripe with the same distribution. The performance of rebuild operations may be improved, and time of rebuild operations may be reduced.

Abstract: Techniques manage an encryption key in a storage system. The techniques involve: transmitting an encryption key request from a storage management component to a key management service component; obtaining, via the key management service component, an encryption key encrypted by the key management service component based on the encryption key request; providing the obtained encrypted encryption key to the storage management component; maintaining, in the storage management component, correspondence between the encrypted encryption key and a storage device; and registering, according to the correspondence, the encrypted encryption key corresponding to the storage device to an encryption hardware unit, such that the encryption hardware unit can decrypt the encrypted encryption key to obtain the encryption key corresponding to the storage device. Effective management of the encryption key is thus realized.

Abstract: Techniques perform failure recovery of a storage device. The techniques involve: determining, based on failure data indicating at least one failed disk, whether the at least one failed disk comprises a system disk associated with an extent pool of the storage device, the extent pool being built based on system disks and user disks; in response to determining that the at least one failed disk comprises a system disk, rebuilding the user data of the system disk to one or more further disks associated with the extent pool; and in response to the system disk being replaced with an updated system disk, restoring the rebuilt user data from the one or more further disks to the updated system disk, an association of the system disk with the extent pool being maintained until the system disk is replaced by the updated system disk.

Abstract: Deuterated polymer-biomolecule conjugates and the synthesis and use of deuterated polymer-biomolecule conjugates for detecting the location of specific molecules, e.g., cell surface molecules, in a subject, and for imaging various processes within the body, for detecting the location of molecules associated with disease pathology, and for monitoring disease progression are disclosed.

Abstract: Techniques provide for data rebuilding in a storage system. The techniques involve: in response to failure of a first disk in the storage system, determining a second disk having a high risk of failure in the storage system; determining whether the second disk contains a second data block that is associated with a first data block to be rebuilt in the first disk, the first and second data blocks being from a same data stripe in the storage system; and in response to determining that the second disk contains the second data block and the second data block has not yet been replicated into a third disk for backup in the storage system, reading the second data block from the second disk to rebuild the first data block, and replicating the read second data block into the third disk.

Abstract: Techniques for processing data involve: receiving a request for moving data from a first slice group in a first logical unit to a second logical unit; determining, based on the request, a second slice group from the second logical unit, the size of the second slice group being larger than or equal to the size of the first slice group; and moving data in the first slice group into the second slice group. Such techniques enable moving data into slices in a specified address range in a specified logical unit, moving data into appropriate slices in a target logical unit when data cannot be moved to slices in a specific address range because an address range is not specified or a specified address range is unavailable can be achieved, and moving disk extents (DEs) by a Redundant Array of Multi-Core Disks (MCR) and redistributing IOs between disk extents.

Abstract: Techniques for copying data involve: in response to receiving a request for copying data in a source address to a destination address, sending a first query and a second query to a first array associated with the source address and a second array associated with the destination address; receiving, from the first array, a first identifier as a response to the first query, the first identifier indicating a first logical storage unit in the first storage array corresponding to the source address; receiving, from the second array, a second identifier as a response to the second query, the second identifier indicating a second logical storage unit in the second array corresponding to the destination address; and triggering, based on the first and second identifiers, an inter-array data copy to perform copying the data. The first and second identifiers are globally unique at least for the storage array being triggered.

Abstract: In accordance with certain techniques, at a first processor of a dual-processor storage system, a change in an initial logical unit corresponding to a storage area in a physical storage device of the storage system is detected. Based on the change in the initial logical unit, a plurality of update operations to be performed on a mapped logical unit driver mapping a plurality of initial logical units including the initial logical unit to a plurality of mapped logical units are determined. An indication of the plurality of update operations is sent to a second processor of the storage system, to cause the second processor to perform the plurality of update operations on a peer mapped logical unit driver associated with the mapped logical unit driver.

Abstract: State information indicates wear levels of respective storage devices and free spaces in the respective storage devices. In response to receiving a request for allocating storage space to the storage system from the storage resource pool, corresponding available spaces in the respective storage devices are determined on the basis of the wear level and the free spaces of the respective storage devices, here the corresponding available spaces represent storage spaces in the respective storage devices which are allocatable to the storage system. A group of storage devices are selected from a plurality of storage devices on the basis of the corresponding available spaces. Requested storage spaces are allocated to the storage system from available spaces in the group of storage devices. Thereby, wear levels of various storage devices in the resource pool may be balanced, and further the overall life of the resource pool may be prolonged.

Abstract: Techniques perform data recovery. The techniques involve: in response to receiving to-be-written data at a first cache module, storing metadata in the data into a first non-volatile cache of the first cache module. The techniques further involve storing user data in the data into a first volatile cache of the first cache module. The techniques further involve sending the metadata and the user data to a second cache module for performing data recovery on the user data. Accordingly, a larger and better guaranteed data storage space may be provided to a cache data backup/recovery system without a need to increase the battery supply capacity and even without a battery.

Abstract: Techniques for managing storage devices involve: combining storage devices in a redundant array of independent disks (RAID) into a group of devices in an order of physical storage capacities; determining a first number of device sets based on a number of devices in the group and a threshold number of devices to be divided into each set, the number of the devices being greater than the threshold number; selecting at least one capacity promotion set from the group, each capacity promotion set including a second number of devices having a same physical capacity, the second number being equal to a sum of a width of the RAID and a number of devices in each set that is reserved; and forming the first number of sets by combining each of capacity promotion set and devices in the group other than each capacity promotion set.

Abstract: Techniques involve managing a storage system. In accordance with the techniques, a plurality of copies of metadata of the storage system are read from a plurality of storage devices in a resource pool of the storage system. The resource pool includes a first number of storage devices, and the metadata describes configuration information of the storage system. A second number of copies are selected from the plurality of copies based on version information in the plurality of copies, where the second number of copies comprises the metadata in the same version. It is determined whether a relation between the first number and the second number satisfies a predetermined condition. The second number of copies are identified as trusted metadata based on determining the relation satisfies the predetermined condition. With the foregoing example implementation, the metadata in the storage system may be managed with higher reliability.

Abstract: Data access techniques involve: determining whether there is a copy operation that is being performed from a first LU to a second LU in response to receiving a write operation request for a first data block in the first logic unit (LU); detecting a copy status of data in the first data block in response to determining that there is the copy operation that is being performed; and determining a processing strategy of the write operation request during execution of the copy operation based on the copy status.

Abstract: Techniques perform resource reallocation for a disk system. Such techniques involve: determining, based on conditions of allocated disk extents in a plurality of disks and wear levels of the plurality of disks, an enhanced neighbor matrix characterizing both distribution evenness of the disk extents on the plurality of disks and the wear levels of the plurality of disks; and performing a resource reallocation operation on the plurality of disks based on the enhanced neighbor matrix. Accordingly, it is possible to, through the enhanced neighbor matrix that is based on the wear level, simultaneously consider both the distribution evenness of disk extents and the wear level of the disk while performing resource reallocation, thereby avoiding the problem of ping-pang resource reallocation caused by inconsistent standards between different resource reallocation methods, and having good compatibility with existing storage systems.

Abstract: Techniques manage an encryption key in a storage system. The techniques involve: transmitting an encryption key request from a storage management component to a key management service component; obtaining, via the key management service component, an encryption key encrypted by the key management service component based on the encryption key request; providing the obtained encrypted encryption key to the storage management component; maintaining, in the storage management component, correspondence between the encrypted encryption key and a storage device; and registering, according to the correspondence, the encrypted encryption key corresponding to the storage device to an encryption hardware unit, such that the encryption hardware unit can decrypt the encrypted encryption key to obtain the encryption key corresponding to the storage device. Effective management of the encryption key thus realized.

Abstract: Techniques for copying data involve: in response to receiving a request for copying data in a source address to a destination address, sending a first query and a second query to a first array associated with the source address and a second array associated with the destination address; receiving, from the first array, a first identifier as a response to the first query, the first identifier indicating a first logical storage unit in the first storage array corresponding to the source address; receiving, from the second array, a second identifier as a response to the second query, the second identifier indicating a second logical storage unit in the second array corresponding to the destination address; and triggering, based on the first and second identifiers, an inter-array data copy to perform copying the data. The first and second identifiers are globally unique at least for the storage array being triggered.

Abstract: Techniques perform I/O management. The techniques involve: in response to receiving an I/O request for a redundant array of independent disks (RAID), determining a stripe of the RAID related to the I/O request; determining metadata corresponding to the stripe, the metadata indicating validity of current data in a corresponding data block of the RAID, the data block comprising one or more stripes; in response to the metadata indicating that the current data is valid, executing the I/O request by accessing the RAID; and in response to the metadata indicating that the current data is invalid, responding to the I/O request with zero data as the current data. Accordingly, disk access is reduced, metadata cache efficiency is increased, I/O performance is improved and the RAID reliability is enhanced.

Abstract: In accordance with certain techniques, at a first processor of a dual-processor storage system, a change in an initial logical unit corresponding to a storage area in a physical storage device of the storage system is detected. Based on the change in the initial logical unit, a plurality of update operations to be performed on a mapped logical unit driver mapping a plurality of initial logical units including the initial logical unit to a plurality of mapped logical units are determined. An indication of the plurality of update operations is sent to a second processor of the storage system, to cause the second processor to perform the plurality of update operations on a peer mapped logical unit driver associated with the mapped logical unit driver. Accordingly, there is improved performance of the dual-processor storage system.

Abstract: State information indicates wear levels of respective storage devices and free spaces in the respective storage devices. In response to receiving a request for allocating storage space to the storage system from the storage resource pool, corresponding available spaces in the respective storage devices are determined on the basis of the wear level and the free spaces of the respective storage devices, here the corresponding available spaces represent storage spaces in the respective storage devices which are allocatable to the storage system. A group of storage devices are selected from a plurality of storage devices on the basis of the corresponding available spaces. Requested storage spaces are allocated to the storage system from available spaces in the group of storage devices. Thereby, wear levels of various storage devices in the resource pool may be balanced, and further the overall life of the resource pool may be prolonged.