Abstract: A method of preparing cathode particles using a co-precipitation reaction in a reactor is disclosed. A feed stream (a) containing metal cations is fed into the reactor, and a feed stream (b) containing anions is fed into the reactor, wherein a ratio of the metal cations in the feed stream (a) is continuously changed from A1 at time t1 to A2 at time t2. The feed stream (a) and the feed stream (b) are contacted in the reactor to form precipitated precursor particles, and at least one transition metal component in the particle has a non-linear continuous concentration gradient profile over at least a portion along a thickness direction of the particle.

Abstract: Techniques for managing metadata storage units involve: in response to receiving, from a client, a request for allocating a target number of metadata storage units, determining a first number of available metadata storage units remaining in a metadata storage space of a storage system after the allocation is performed; and if the first number is not less than a reserved number, allocating the target number of metadata storage units from the metadata storage space for the client to use, wherein the reserved number is associated with a usage condition of the metadata storage units in the storage system. Accordingly, such techniques can effectively manage metadata and improve the performance of a system.

Abstract: Techniques for managing metadata storage units involve: in response to receiving, from a client, a request for allocating a target number of metadata storage units, determining a first number of available metadata storage units remaining in a metadata storage space of a storage system after the allocation is performed; and if the first number is not less than a reserved number, allocating the target number of metadata storage units from the metadata storage space for the client to use, wherein the reserved number is associated with a usage condition of the metadata storage units in the storage system. Accordingly, such techniques can effectively manage metadata and improve the performance of a system.

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 redundant arrays of independent drives (RAID). The techniques involve: in response to a target stripe to be built in the RAID, determining, from a resource pool, whether there are spare extents associated with at least one system disk. The techniques further involve: in response to determining that there are spare extents associated with at least one system disk, determining an adjacent relationship of used extents associated with the at least one system disk within a RAID stripe. The techniques further involve: determining, based on the adjacent relationship and the spare extents, an extent for building the target stripe. Accordingly, the total number of the RAID stripes including extents associated with the system disks can be reduced significantly, and a balance can be achieved within spare extents associated with system disks and spare extents associated with user disks for building a RAID stripe.

Abstract: Techniques manage a redundant array of independent disks. In such a technique, an instruction to expand the RAID is received, the RAID being formed by a first group of storage devices and including a first group of RAID extents. A second group of RAID extents created on a second group of storage devices and logical units are created on the second group of RAID extents. In response to receiving an indication for a failure of the creation of the second group of RAID extents or the logical units, a notification is generated for indicating a failure of the expansion of the RAID without triggering a shuffling operation, the shuffling operation causing storage extents in the first and second groups of RAID extents to be distributed in the first and second groups of storage devices.

Abstract: Techniques involve determining updated disk sets. The techniques further involve determining, from the updated disk sets, a target disk set for a storage unit associated with a plurality of storage disks. The techniques further involve determining position information of disk slices corresponding to the storage unit in the plurality of storage disks, in which the position information indicates respective updated disk sets in which the disk slices are located. The techniques further involve in accordance with a determination that an updated disk set indicated by position information of at least one of the disk slices is different from the target disk set, moving data in the at least one disk slice to the target disk set. Accordingly, an arrangement of a storage units across different disk sets can be avoided, and utilization rates of a plurality of storage disks can be made more uniform.

Abstract: Techniques involve determining updated disk sets. The techniques further involve determining, from the updated disk sets, a target disk set for a storage unit associated with a plurality of storage disks. The techniques further involve determining position information of disk slices corresponding to the storage unit in the plurality of storage disks, in which the position information indicates respective updated disk sets in which the disk slices are located. The techniques further involve in accordance with a determination that an updated disk set indicated by position information of at least one of the disk slices is different from the target disk set, moving data in the at least one disk slice to the target disk set. Accordingly, an arrangement of a storage units across different disk sets can be avoided, and utilization rates of a plurality of storage disks can be made more uniform.

Abstract: Techniques manage a redundant array of independent disks. In such a technique, an instruction to expand the RAID is received, the RAID being formed by a first group of storage devices and including a first group of RAID extents. A second group of RAID extents created on a second group of storage devices and logical units are created on the second group of RAID extents. In response to receiving an indication for a failure of the creation of the second group of RAID extents or the logical units, a notification is generated for indicating a failure of the expansion of the RAID without triggering a shuffling operation, the shuffling operation causing storage extents in the first and second groups of RAID extents to be distributed in the first and second groups of storage devices.

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 redundant arrays of independent drives (RAID). The techniques involve: in response to a target stripe to be built in the RAID, determining, from a resource pool, whether there are spare extents associated with at least one system disk. The techniques further involve: in response to determining that there are spare extents associated with at least one system disk, determining an adjacent relationship of used extents associated with the at least one system disk within a RAID stripe. The techniques further involve: determining, based on the adjacent relationship and the spare extents, an extent for building the target stripe. Accordingly, the total number of the RAID stripes including extents associated with the system disks can be reduced significantly, and a balance can be achieved within spare extents associated with system disks and spare extents associated with user disks for building a RAID stripe.