Abstract: Storage management techniques involve: acquiring target data in a target storage page in a memory; determining, based on the target data, check information and identification information associated with the target data, the check information being used to verify whether the target data is correct and the identification information being used to identify the target data; and determining, based on the identification information, storage information associated with the target data and the check information, the storage information indicating whether to store the target data and the check information to a persistent storage device. Therefore, the processing efficiency can be improved, and the input/output (I/O) performance can be improved.

Abstract: A storage management technique involves: selecting a first disk from a plurality of disks in a storage system as an anchor disk; allocating a first backup slice from the plurality of disks to a redundant array of independent disks (RAID) associated with the first disk, the first RAID including at least a slice allocated from the first disk; and if it is detected that there is an inaccessible disk in the plurality of disks, determining a backup slice for a slice of the inaccessible disk based on the allocation of the first backup slice to the first RAID, for use in data reconstruction of the inaccessible disk. This can ensure that a backup slice can always be successfully determined for slices of an inaccessible disk without introducing additional time complexity.

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 creating an extent array in a storage system, in response to receiving a request to generate an extent array using idle extents in storage devices, a width of an extent stripe is determined, and a size of the extent array is designated by the storage system. A first extent group and a second extent group are respectively selected from the storage devices based on the width to form a first extent stripe and a second extent stripe, and a first extent at a given position in the first extent group and a second extent at a given position in the second extent group are respectively located in different storage devices. Based on the first extent stripe and the second extent stripe, an address mapping representing the extent array is generated. The address mapping includes association between extent identifiers of extents and extent indexes of the extents.

Abstract: Techniques for managing a storage unit involve: determining space usage indicators of a storage system including disks, each disk is divided into disk slices, and at least part of the disk slices are organized into a storage unit. The techniques further involve: determining a target priority of a data migration task based on the space usage indicators, wherein the data migration task is used to migrate data in a group of disk slices allocated to at least one storage unit to another group of disk slices. The techniques further involve: if the target priority is different from a current priority of the data migration task, adjusting the current priority of the data migration task to the target priority, and determining system resources for the data migration task based on the target priority. Accordingly, a priority of a data migration task can be dynamically adjusted to accommodate different scenarios.

Abstract: Techniques manage a disk array. Such techniques involve determining, from one or more disk arrays constructed based on a plurality of disks, a target disk array to be restriped, the target disk array being associated with disk slices on different disks and including a stripe to be reconstructed, the stripe including extents located in the disk slices; determining, from the disk slices, a first disk slice on which data migration is to be performed, a first extent of the extents being located in the first disk slice; allocating, on the plurality of disks, a second disk slice for storing data from the first disk slice; and reconstructing the stripe by migrating data from the first extent of the first disk slice into the second disk slice. Such techniques significantly reduce the number of input/output operations during stripe reconstruction while avoiding waste of storage space.

Abstract: Techniques perform storage management. The techniques involve: in response to a target request for a target redundant array of independent disks (RAID), determining that data in a first storage block associated with the target RAID needs to be moved or copied, wherein the target request includes one of the following: a restriping request, a type conversion request, or a rebalancing request; creating an intermediate RAID associated with an idle second storage block; and copying the data in the first storage block to a corresponding storage space in the intermediate RAID to write at least part of the data in the second storage block. Based on this mode, RAID restriping, type conversion, or rebalancing can be implemented efficiently.

Abstract: Techniques involve determining whether data read from a redundant array of independent disks (RAID) is corrupted, the RAID including two parity disks. The techniques further involve determining, based on the read data being corrupted, whether single-disk data recovery can recover the corrupted data. The techniques further involve recovering, based on the single-disk data recovery failing to recover the corrupted data, the corrupted data using dual-disk data recovery. Such techniques may present a recovery solution for silent data corruption of a RAID with two parity disks, such that corrupted data can be recovered in the case of either a single-disk failure or a dual-disk failure, thereby improving the storage system performance.

Abstract: Techniques perform data storage. Such techniques may involve writing metadata to a first cache of a first processor, the metadata indicating allocation of a storage resource to user data. Such techniques may further involve determining an address range of the metadata in the first cache. Such techniques may further involve copying only data stored in the address range in the first cache to a second cache of a second processor. Accordingly, the data transmission volume between two processors is reduced, which helps to improve the overall performance of a storage system.

Abstract: Techniques for providing information involve: obtaining, from a first device for updating information, a first copy of the updated information, where a second copy of the information prior to the updating is cached in a first buffer acting as an active buffer and the second copy is provided in response to receiving a first request for providing the information from a second device; caching the first copy in a second buffer acting as a standby buffer; in response to the first copy being cached in the second buffer, switching the second buffer to the active buffer and switching the first buffer to the standby buffer; and in response to receiving a second request for providing the information from the second device, providing, to the second device, the first copy cached in the active buffer. Such techniques can ensure the consistency of the provided information without a lock.

Abstract: Techniques involve: determining corresponding valid metadata rates of a plurality of metadata blocks stored in a metadata storage area of a storage system, the valid metadata rate of each metadata block indicating a ratio of valid metadata in the metadata block to all metadata in the metadata block; selecting a predetermined number of metadata blocks having a valid metadata rate lower than a first valid metadata rate threshold from the plurality of metadata blocks; storing valid metadata in the predetermined number of metadata blocks into at least one metadata block following the plurality of metadata blocks in the metadata storage area; and making the valid metadata in the predetermined number of metadata blocks invalid. Accordingly, such techniques can improve the efficiency of the storage system.

Abstract: Techniques involve dividing a disk in RAID into a plurality of slices, and the plurality of slices include a first slice and a second slice with a first size. The techniques further involve dividing the second slice into a plurality of sub-slices, and each sub-slice in the plurality of sub-slices has a second size smaller than the first size. The techniques further involve forming a first stripe set for storing user data using the first slice and forming a second stripe set for storing metadata using the sub-slices. Such techniques enable configuring a smaller slice size for the set stripe for the metadata, and thus the granularity of storage and migration for the metadata can be reduced, and the metadata can be distributed into more disks in the RAID.

Abstract: Techniques manage a storage system. In accordance with such techniques, an access request for target data is received; a storage position of the target data is determined, the storage position indicating one of a storage device and a cache; a target element corresponding to the target data is determined from a first replacement list and a second replacement list associated with the first replacement list based on the storage position, the first replacement list including at least a counting element, the counting element indicating an access count of data in the storage device, the second replacement list including a low-frequency access element, the low-frequency access element indicating a cache page with a low access frequency in the cache; and a position of the target element in a replacement list where the target element exist is updated. Therefore, the overall performance of the storage system can be improved.

Abstract: Embodiments of the present disclosure relate to a method, device and a computer program product for managing a storage system. The storage system includes a disk array. A method includes determining, based on a first number of disks in the disk array, a second number of spare disks for the disk array. The method further includes creating a spare disk array with the second number of spare disks. The method further includes, in response to a first disk in the disk array failing, allocating a spare logic storage unit from the spare disk array for rebuilding the first disk. In addition, the method further includes rebuilding the first disk with the spare logic storage unit.

Abstract: Techniques for managing data involve determining multiple indications related to a status of a stripe, including a first indication to indicate whether a group of disks related to the stripe is available, a second indication to indicate whether to rebuild the stripe, and a third indication to retain a value of the first indication when a disk is unavailable; in response to detecting that a disk in the group of disks is unavailable, updating the first indication to indicate that the disk is unavailable; and in response to receiving a write operation, determining an updating to the third indication with a first value of the updated first indication; and in response to determining that the unavailable disk is available again within a predetermined time period, updating the second indication with a current value of the updated third indication, to indicate rebuilding of the stripe.

Abstract: Techniques for storage management involve determining an independent redundant disk array RAID associated with a first set of storage disks, a first portion of storage blocks corresponding to the RAID being located in the first set of storage disks; determining, from the first set of storage disks, a plurality of storage disks corresponding to the RAID; and updating a set of association degrees of the first set of storage disks to indicate data coupling between storage disk pairs in the plurality of storage disks. Accordingly, the data coupling degree between storage disks can be determined more accurately.

Abstract: Techniques manage a cache. Such techniques involve creating a primary cache by a cache management module in a storage system. Such techniques further involve: in response to the primary cache being created, sending a first request to a hardware management module to obtain first information about a first virtual disk. Such techniques further involve: in response to receiving the first information from the hardware management module, creating a secondary cache using the first virtual disk. Such techniques further involve: in response to an available capacity of the primary cache being below a predetermined threshold, flushing at least one cache page in the primary cache to the secondary cache. In certain techniques, it is possible to use spare extents in the disk array to create the secondary cache to increase a total capacity of the cache in the system, thereby improving the access performance of the system.

Abstract: Techniques for managing a storage disk involve monitoring a duration of a fault of a faulted storage disk, wherein the faulted storage disk includes a first disk slice configured to store metadata and a second disk slice configured to store user data. The techniques further involve, in response to the duration reaching a first threshold value, replacing the first disk slice with a first available disk slice in a first non-faulted storage disk. The techniques further involve, in response to the duration reaching a second threshold value greater than the first threshold value, replacing the second disk slice with a second available disk slice in a second non-faulted storage disk. Accordingly, fault monitoring windows with different lengths are applied to disk slices for different logical tiers in the faulted storage disk. In this way, the reliability of data of a metadata tier can be effectively improved.

Abstract: Techniques for storage management involve: determining expected usage time of a first storage disk in a set of storage disks, at least a part of the set of storage disks being configured to form at least one redundant array of independent disks (RAID); moving data in a first storage block, associated with a first RAID in the at least one RAID, in the first storage disk to a second storage block in a second storage disk in the set of storage disks based on a determination that the expected usage time is less than a predetermined threshold value; and replacing the first storage block with the second storage block, so that the second storage block is associated with the first RAID. Based on this manner, the stability of a storage system can be improved.

Abstract: Techniques for managing a storage disk involve monitoring a duration of a fault of a faulted storage disk, wherein the faulted storage disk includes a first disk slice configured to store metadata and a second disk slice configured to store user data. The techniques further involve, in response to the duration reaching a first threshold value, replacing the first disk slice with a first available disk slice in a first non-faulted storage disk. The techniques further involve, in response to the duration reaching a second threshold value greater than the first threshold value, replacing the second disk slice with a second available disk slice in a second non-faulted storage disk. Accordingly, fault monitoring windows with different lengths are applied to disk slices for different logical tiers in the faulted storage disk. In this way, the reliability of data of a metadata tier can be effectively improved.