METHOD, APPARATUS AND COMPUTER PROGRAM PRODUCT FOR STORING DATA

• US 20200133858A1
• Filed: 09/12/2019
• Published: 04/30/2020
• Est. Priority Date: 10/26/2018
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Zhang, Leihu, Gong, Chen, Zhang, Ming, Fang, Hao
• Granted Patent: US 11,048,629 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 12/0802 Addressing of a memory level in which the access to the desired data or data block requires associative addressing means, e.g. caches
• CPC Class Codes: G06F 12/0868 Data transfer between cache memory and other subsystems, e.g. storage devices or host systems
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/312 In storage controller
• CPC Class Codes: G06F 2212/401 Compressed data
• CPC Class Codes: G06F 2212/463 File
• CPC Class Codes: G06F 2212/502 using adaptive policy
• CPC Class Codes: G06F 2212/60 Details of cache memory
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0638 Organizing or formatting or addressing of data
• CPC Class Codes: G06F 3/0655 Vertical data movement, i.e. input-output transfer; data movement between one or more hosts and one or more storage devices
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0671 In-line storage system
• CPC Class Codes: G06F 3/0673 Single storage device

Abstract

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.

Claims

1. A method of storing data, comprising:

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.

2. The method of claim 1, wherein determining the type of the file comprises:

obtaining a file name of the file from the request; and

determining the type of the file based on the file name.

3. The method of claim 2, wherein the file name comprises a main file name and an extension file name, and wherein determining the type based on the file name comprises:

matching the extension file name in the file name with a predetermined extension file name indicating a compressed file; and

in response to the extension file name matching the predetermined extension file name, determining that the file is a compressed file.

4. The method of claim 1, wherein determining the type of the file comprises:

in response to the file being created, obtaining from the file a sequence of bytes indicating the type of the file; and

determining the type of the file based on the sequence of bytes.

5. The method of claim 4, wherein determining the type based on the sequence of bytes comprises:

matching the sequence of bytes with a predetermined sequence of bytes indicating a compressed file; and

in response to the sequence of bytes matching the predetermined sequence of bytes, determining that the file is a compressed file.

6. The method of claim 1, wherein determining the type of the file comprises:

in response to the file being created, obtaining metadata of a file system associated with the file, wherein the type of the file is recorded in the metadata of the file system; and

determining the type of the file based on the metadata of the file system.

7. The method of claim 1, wherein determining the compression property of the data comprises:

in response to the type indicating that the file is a compressed file, determining that the data is incompressible; and

in response to the type indicating that the file is an uncompressed file, determining that the data is compressible.

8. The method of claim 1, wherein storing the data in the storage area comprises:

generating a tag indicating the compression property;

storing the tag in association with the data into a cache;

in response to the data being stored into the cache, returning a response to the request; and

flushing the data from the cache to the storage area based on the tag associated with the data.

9. The method of claim 8, wherein flushing the data to the storage area comprises:

in response to the tag indicating that the data is incompressible, flushing the uncompressed data to the storage area.

10. The method of claim 8, wherein flushing the data from the cache to the storage area comprises:

in response to the tag indicating that the data is compressible, compressing the data;

determining a ratio of a first size of the compressed data to a second size of the uncompressed data;

in response to the ratio being below a predetermined threshold, flushing the compressed data to the storage area; and

in response to the ratio exceeding the predetermined threshold, flushing the uncompressed data to the storage area.

11. A device for storing data, comprising:

at least one processing unit;

at least one memory coupled to the at least one processing unit and storing instructions which, when executed by the at least one processing unit cause the device to perform acts comprising;

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.

12. The device of claim 11, wherein determining the type of the file comprises:

obtaining a file name of the file from the request; and

determining the type of the file based on the file name.

13. The device of claim 12, wherein the file name comprises a main file name and an extension file name, and wherein determining the type based on the file name comprises:

matching the extension file name in the file name with a predetermined extension file name indicating a compressed file; and

in response to the extension file name matching the predetermined extension file name, determining that the file is a compressed file.

14. The device of claim 11, wherein determining the type of the file comprises:

in response to the file being created, obtaining from the file a sequence of bytes indicating the type of the file; and

determining the type of the file based on the sequence of bytes.

15. The device of claim 14, wherein determining the type, based on the sequence of bytes, comprises:

matching the sequence of bytes with a predetermined sequence of bytes indicating a compressed file; and

in response to the sequence of bytes matching the predetermined sequence of bytes, determining that the file is a compressed file.

16. The device of claim 11, wherein determining the type of the file comprises:

in response to the file being created, obtaining metadata of a file system associated with the file, wherein the type of the file is recorded in the metadata of the file system; and

determining the type of the file based on the metadata of the file system.

17. The device of claim 11, wherein determining the compression property of the data comprises:

in response to the type indicating that the file is a compressed file, determining that the data is incompressible; and

in response to the type indicating that the file is an uncompressed file, determining that the data is compressible.

18. The device of claim 11, wherein storing the data in the storage area comprises:

generating a tag indicating the compression property;

storing the tag in association with the data into a cache;

in response to the data being stored into the cache, returning a response to the request; and

flushing the data from the cache to the storage area based on the tag associated with the data.

19. The device of claim 18, wherein flushing the data to the storage area comprises:

in response to the tag indicating that the data is incompressible, flushing the uncompressed data to the storage area.

20. The device of claim 18, wherein flushing the data from the cache to the storage area comprises:

in response to the tag indicating that the data is compressible, compressing the data;

determining a ratio of a first size of the compressed data to a second size of the uncompressed data;

in response to the ratio being below a predetermined threshold, flushing the compressed data to the storage area; and

in response to the ratio exceeding the predetermined threshold, flushing the uncompressed data to the storage area.

21. A computer program product having a non-transitory computer readable medium which stores a set of instructions to store data;

the set of instructions, when carried out by computerized circuitry, causing the computerized circuitry to perform a method of;

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.