Emc IP Holding Company LLC

Dell Products Inc.

Emc Corporation

Chen Gong

Lester Zhang

Huan Chen

Ming Lei Zhang

Shuo Lv

Denny Dengyu Wang

Leihu Zhang

Leon Zhang

Ming Zhang

Qiaosheng Zhou

Joe Jian Liu

Jian Gao

Geng Han

Henry Hao Fang

Junping Zhao

Sheng Wang

Wei Cui

Yingchao Zhou

Hao Fang

Changxu Jiang

Chao Han

Walter Wang

Fei Wang

Donglei Wang

Jian Liu

Weigang Zhong

Yongli Wang

Tao Sun

Ruiyong Jia

Lei Gao

Wai Chuen Yim

Kevin Xu

Sitaram D Pawar

Jian Qiang Liu

Wei Kang

Tianfang Xiong

Qi Qu

Weibing Zhang

Dapeng Chi

Bean Bin Zhao

Xiaohua Fan

Guoyu Hu

Congyue Gu

Brown Zan Liu

Ted Guangkai Zhang

Huamin Chen

Yanbei Wang

Joseph Yuan Gu

Liangfeng Zhu

Techniques for recovering data involve determining, in response to a request of user equipment, at least one storage block to be recovered under the request, wherein the at least one storage block is composed of storage regions. Such techniques further involve acquiring a cache type of the at least one storage block in a buffer, wherein the cache type is based on the number of recovery regions indicated by the buffer for the at least one storage block. Such techniques further involve determining, based on the cache type, cache regions from regions composing the at least one storage block. Such techniques further involve updating recovery data in the cache regions to the buffer. Such techniques further involve recovering, in response to a recovery confirmation operation, data of the at least one storage block in the user equipment based on the recovery data cached in the buffer after the update.

Method, electronic device, and computer program product for recovering data

Techniques perform data detection. Such techniques involve determining, based on a start sector address of a first mapping range composed of sectors in a physical address space, a first mapping region where the start sector address is located, the first mapping range corresponding to a first virtual block. Such techniques further involve comparing the first mapping region with a second mapping region, a second mapping range corresponding to a second virtual block different from the first virtual block at least partially corresponding to the second mapping region. Such techniques further involve comparing the first mapping range with the second mapping range in response to the first mapping region being the same as the second mapping region. Such techniques further involve determining that the first mapping range overlaps the second mapping range in response to that the first mapping range and the second mapping range have a common range.

Method, electronic device, and computer program product for data detection

A technique for computing resource management involves determining a first resource request frequency based on the number of trigger signals received from a storage device during a first period. The trigger signals are generated when a data amount of modified metadata stored in the storage device reaches a threshold data amount. The technique further involves determining a second resource request frequency based on the number of trigger signals received from the storage device during a second period subsequent to the first period. The technique further involves adjusting computing resources for performing an operation of copying the modified metadata in the storage device to a storage medium based on a comparison of the first resource request frequency and the second resource request frequency. Accordingly, computing resources can be fully utilized, and an operation of copying modified metadata to a magnetic disk can be timely performed.

Computing resource management method, electronic equipment and program product

Techniques for de-duplicating data involve: determining a target physical block in a first storage device. The techniques further involve: determining a compression ratio of a target data block in a plurality of data blocks to be transferred. The techniques further involve: determining a target hash value of the target data block in response to the compression ratio being lower than a threshold compression ratio. The techniques further involve: determining a de-duplication operation for the target data block based on the target hash value and a de-duplication hash table, the de-duplication hash table storing hash values of data blocks that have been transferred from the first storage device to the second storage device. Accordingly, the amount of data that needs to be transferred can be reduced, and the storage space of the storage devices can be improved, thus increasing the resource utilization and improving the user experience.

Method, device, and computer program product for de-duplicating data

Techniques for transferring data involve: determining a first physical block in a first storage device, the first physical block having a plurality of data blocks stored thereon. The techniques further involve: determining, based on a first data block of the plurality of data blocks, whether a set of logically contiguous data blocks that comprise the first data block exist in the first physical block, the set of data blocks having a target heat greater than a threshold heat. The techniques further involve: transferring, in response to the existence of the set of data blocks in the first physical block, the set of data blocks into a second storage device for contiguous storage in a second physical block of the second storage device. Accordingly, relatively high heat data blocks are transferred to device with higher access speed, thereby reducing data access time, increasing data processing efficiency, and improving user experience.

Method, device and computer program product for transferring data

Techniques for data storage involve selecting a target Redundant Array of Independent Disks (RAID) from a plurality of RAIDs in a storage resource pool. Such techniques further involve determining a local neighbor matrix of the target RAID based on the target RAID, wherein the local neighbor matrix indicates distribution of a plurality of storage extents of a plurality of RAID extents of the target RAID on the storage resource pool. Such techniques further involve performing a resource reallocating operation on the storage resource pool based on the local neighbor matrix. Accordingly, a local neighbor matrix can be calculated at the granularity of an individual RAID, and the local neighbor matrix can be applied to balance a local neighboring relationship, so as to ensure overall balance of the neighbor matrix of the entire storage resource pool and improve IO performance.

Method, electronic device, and computer program product for data storage

In techniques for flushing data, based on a maturity level of a storage segment, the storage segment is inserted into a list to be flushed corresponding to the maturity level in a plurality of lists to be flushed, the plurality of lists to be flushed respectively correspond to different maturity levels, and the maturity level at least indicates a proportion of the number of data-written blocks to the total number of blocks of the storage segment; and the list to be flushed for the corresponding maturity level in the plurality of lists to be flushed is flushed to a disk array according to a descending order of the maturity levels. In this way, the bandwidth utilization of the disk array can be improved.

Method, electronic device, and computer program product for flushing data

A method of performing synchronous replication from a primary storage system apparatus (PSSA) to a secondary storage system apparatus (SSSA) is provided. The method includes (a) in response to write requests received by the PSSA, (i) calculating metadata changes by the PSSA for accommodating the write requests, (ii) generating, by the PSSA, metadata journal log entries that describe the metadata changes, and (iii) mirroring the metadata journal log entries from the PSSA to the SSSA; (b) regenerating the metadata changes by the SSSA based on the metadata journal log entries mirrored from the PSSA to the SSSA; and (c) writing the regenerated metadata changes to persistent storage of the SSSA. A method performed by the SSSA is also provided. An apparatus, system, and computer program product for performing similar methods are also provided.

Reducing redundancy in synchronous replication of metadata with a journal log

Techniques for flushing metadata involve: receiving a flushing request, the flushing request instructing to flush metadata in at least one cache region to a persistent storage device; acquiring a plurality of target indicators, the target indicator at least indicating a type of a cache region and a block in the cache region, where the plurality of target indicators are classified based on types of cache regions indicated by the target indicators among the plurality of target indicators; determining, from the plurality of target indicators, at least one target indicator of the same type as the at least one cache region; and flushing metadata in a block indicated by the at least one target indicator. Such techniques avoid flushing a cache region that does not need to be flushed, shortens the response time to the flushing request, and reduces the occupancy of system resources.

Method, electronic device and computer program product for flushing metadata

Techniques for tracking a lock involve creating an event comprising object information, and extracting the object information in the event through a thread in a thread pool. Such techniques further involve recording lock information comprising the object information according to a determination that the thread executes a lock operation. Such a lock tracking technique for a threading model can record lock information of an object when a thread performs locking and unlocking, and realize tracking of a lock operation and generating a lock analysis report.

Method, device and computer program product for tracking lock

A technique for managing a storage system involves determining, in response to a first write operation on a first data block on a persistent storage device, whether a first group of data corresponding to the first data block is included in a cache; updating the first group of data in the cache if it is determined that the first group of data is included in the cache; and adding the first group of data to an associated data set of the cache to serve as a first record. Accordingly, such a technique can associatively manage different types of cached data corresponding to a data block, thereby optimizing the system performance.

Managing data of different cache types within a storage system

Implementations of the present disclosure relate to method and device for managing a storage system. The method comprises in response to receiving a write request at a storage system, determining whether storage units allocated to a logic storage unit of the storage system are sufficient for data associated with the write request. The method also comprises in response to determining that the allocated storage units are insufficient, allocating a new storage unit to the logic storage unit. The method further comprises updating metadata associated with allocation of the storage units of the storage system, the metadata indicating a mapping between the logic storage unit and the storage units. The method also comprises encrypting the updated metadata. Other implementations of the present disclosure also involve corresponding method, device and computer-readable medium for decryption metadata and recovering the logic storage unit using the decrypted metadata.

Method and device for managing storage system

Techniques provide for data deduplication. Such techniques involve: allocating a storage area in a storage device, the storage area including a first storage segment for storing an incompressible data block and a second storage segment for storing a compressed data block, a first size of the first storage segment being greater than a second size of the second storage segment; in response to receiving a write request, determining whether data block to which the write request is related is compressible; in response to determining that the data block is incompressible, adding header information to the data block to generate a first data segment of the first size; and storing the first data segment in the first storage segment through a deduplication operation. Accordingly, such techniques can increase the flexibility and efficiency of data deduplication.

Method, device, and computer readable medium for data deduplication

Techniques for storage management involve: in accordance with a determination that an input/output (I/O) request of a storage system is received, determining a target storage device to which the I/O request is directed. The techniques further involve: in accordance with a determination that the target storage device is a storage device of a first type, processing the I/O request by accessing a memory of the storage system. The techniques further involve: in accordance with a determination that the target storage device is a storage device of a second type different from the first type, processing the I/O request without accessing the memory, the storage device of the second type having an access speed higher than that of the storage device of the first type. Accordingly, such techniques can improve performance of a storage system.

Optimized access to high-speed storage device

Techniques for storing data involve estimating a hit ratio of a digest cache associated with a target storage device, the digest cache recording a digest of data that is stored in the target storage device after preprocessing; generating, according to a determination that the hit ratio is lower than a predetermined threshold, a digest for target data to be stored and performing the preprocessing; and storing, according to a determination that the digest of the target data is missing in the digest cache, the preprocessed target data in the target storage device, and recording the digest of the target data in the digest cache. Such techniques can achieve good system performance in both cases of high data repetition and low data repetition.

Method, electronic device and computer program product for storing data

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Beijing, China

Chen Gong