Emc IP Holding Company LLC

Leihu Zhang

Chen Gong

Shuo Lv

Ming Lei Zhang

Huan Chen

Hao Fang

Xiaohua Fan

Techniques involve: selecting a stream from a plurality of streams having respective update frequencies, the update frequency of the selected stream matching an update frequency of to-be-written data; determining a label of the data based on a label of the selected stream; and sending a write request for the data to a storage system, the write request comprising the label of the data, so that the storage system performs a write operation for the data based on the stream identified by the label. Accordingly, a write amplification factor can be reduced, thereby increasing the effective life of a storage device and improving read and write performance of the storage system.

Method, device and computer program for data storage

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

Techniques for data writing involve: determining an unavailable storage zone in multiple storage zones of a storage area, wherein each storage zone is used to store a zip header and compressed data corresponding to the zip header; acquiring a reference zip header for the unavailable storage zone, wherein the reference zip header includes metadata indicating a zone length of the unavailable storage zone; and generating consecutive write requests for the storage area based at least on target data to be written to the storage area and the reference zip header, so as to write the target data to available storage zones in the multiple storage zones. Accordingly, rewriting of data can be implemented by constructing large consecutive write requests, thus improving the write performance of the storage device.

Method, device and computer program product for data writing

A data compression technique involves: selecting, from a data block, a plurality of bit strings as sample data. The technique further involves: determining a set of characters included in the sample data. Each character in the set of characters is represented by at least one bit string among the plurality of bit strings. The technique further involves: compressing the data block if statistical characteristics of the set of characters match predetermined statistical characteristics. Accordingly, incompressible data can be filtered out efficiently and accurately, so as to utilize computing resources more efficiently.

Data compression method, electronic device and computer program product

Data overwriting techniques involve: comparing, based on a request for overwriting target data in a storage area to cover original data, a first compression ratio with a second compression ratio; in accordance with a determination that the first compression ratio is larger, compressing the target data into fragments at the first compression ratio; storing the fragments in segments in the storage area, the segments being previously used for storing corresponding fragments of the original data; and storing at least one padding data fragment in at least one free segment interleaved with the segments and/or free sectors in the segments. Accordingly, the overwritten data can be stored in the storage area in a continuous manner, while the write alignment requirement of the storage device can be satisfied, thereby saving the additional read overheads incurred by the write request and enhancing the write performance of the storage device.

Method, device, and computer program product for overwriting data

Computerized techniques involve dividing a plurality of entries included in an indirect block of an inode into a plurality of entry groups. Each non-null entry of the plurality of entries has one of a pointer pointing to an associated data block and an identifier specific to a byte pattern of an associated data block. The techniques further involve determining, for an entry group of the plurality of entry groups, whether entries having an identifier in the entry group all have a same predetermined identifier. The techniques further involve in response to determining that the entries having an identifier in the entry group all have the same predetermined identifier, identifying the entry group as recoverable if the indirect block is corrupted. Such techniques improve reliability and performance of a storage system.

Method, apparatus and computer program product for improving inline pattern detection

Techniques store data. Such techniques involve: in response to receiving a request for writing data to a file, determining a type of the file; determining a compression property of the data based on the determined type; determining a storage area corresponding to the data to be written in a storage device for storing the file; and storing the data into the storage area, based on the compression property. Such techniques can determine, based on a type of a file involved in an input/output (I/O) request, a compression property of the data for the I/O request, and further determine whether a data compression operation is to be performed prior to storing the data. Accordingly, the techniques can avoid an unnecessary compression operation while reducing the storage space required for storing data as much as possible, thereby improving performance of system.

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Beijing, China

Leihu Zhang