METHOD, ELECTRONIC DEVICE AND COMPUTER PROGRAM PRODUCT FOR READING DATA

• US 20200133495A1
• Filed: 10/18/2019
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Yang, Lifeng, Li, Xiongcheng, Xu, Xinlei
• Granted Patent: US 11,314,430 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0673 Single storage device

Abstract

Techniques read data. Such techniques involve: in response to receiving a read request from the user for data on a physical data block, determining whether there is data state information corresponding to the physical data block. The data state information may include a plurality of units for respectively indicating availability of data stored in a plurality of sub-blocks of the physical data block. Such techniques further involve: in response to determining that there is data state information, selecting a target sub-block from the plurality of sub-blocks of the physical storage block based on the data state information. Such techniques further involve: providing the user with data stored in the target sub-block. Such techniques are capable of determining the availability of data at a finer granularity.

Claims

1. A method of reading data, comprising:

in response to receiving a read request from the user for data on a physical data block, determining whether there is data state information corresponding to the physical data block, the data state information comprising a plurality of units for respectively indicating availability of data stored in a plurality of sub-blocks of the physical data block;

in response to determining that there is the data state information, selecting a target sub-block from the plurality of sub-blocks of the physical storage block based on the data state information; and

providing the user with data stored in the target sub-block.

2. The method according to claim 1, further comprising:

in response to determining that the data state information is absent, returning data read failure information.

3. The method according to claim 1, wherein determining whether there is the data state information corresponding to the physical data block comprises:

determining a virtual entry for storing location information of the physical data block according to the read request; and

detecting the data state information from the virtual entry.

4. The method according to claim 1, wherein selecting the target sub-block from the plurality of sub-blocks of the physical storage block based on the data state information comprises:

determining, from the plurality of units of the data state information, a unit marked as available; and

determining a sub-block corresponding to the determined unit as the target sub-block.

5. The method according to claim 1, further comprising:

deleting the data state information after providing the user with the data.

6. The method according to claim 1, further comprising:

in response to receiving a write request to write data to the physical data block, determining a sub-block of the physical data block to which the data is to be written; and

marking, in the data state information, a unit corresponding to the determined sub-block as available.

7. The method according to claim 6, wherein the marking the unit corresponding to the determined sub-block as available comprises:

determining, from the data state information, the unit corresponding to the determined sub-block; and

setting the determined unit to a predetermined value.

8. An electronic device, comprising:

at least one processing unit; and

at least one memory coupled to the at least one processing unit and storing machine-executable instructions, the instructions, when executed by the at least one processing unit, causing the device to perform acts, the acts comprising;

in response to receiving a read request from the user for data on a physical data block, determining whether there is data state information corresponding to the physical data block, the data state information comprising a plurality of units for respectively indicating availability of data stored in a plurality of sub-blocks of the physical data block;

in response to determining that there is the data state information, selecting a target sub-block from the plurality of sub-blocks of the physical storage block based on the data state information; and

providing the user with data stored in the target sub-block.

9. The device according to claim 8, wherein the acts further comprise:

in response to determining that the data state information is absent, returning data read failure information.

10. The device according to claim 9, wherein determining whether there is the data state information corresponding to the physical data block comprises:

determining a virtual entry for storing location information of the physical data block according to the read request; and

detecting the data state information from the virtual entry.

11. The device according to claim 8, wherein selecting the target sub-block from the plurality of sub-blocks of the physical storage block based on the data state information comprises:

determining, from the plurality of units of the data state information, a unit marked as available; and

determining a sub-block corresponding to the determined unit as the target sub-block.

12. The device according to claim 8, wherein the acts further comprise:

deleting the data state information after providing the user with the data.

13. The device according to claim 8, wherein the acts further comprise:

in response to receiving a write request to write data to the physical data block, determining a sub-block of the physical data block to which the data is to be written; and

marking, in the data state information, a unit corresponding to the determined sub-block as available.

14. The device according to claim 13, wherein the marking the unit corresponding to the determined sub-block as available comprises:

determining, from the data state information, the unit corresponding to the determined sub-block; and

setting the determined unit to a predetermined value.

15. A computer program product having a non-transitory computer readable medium which stores a set of instructions to read 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 read request from the user for data on a physical data block, determining whether there is data state information corresponding to the physical data block, the data state information comprising a plurality of units for respectively indicating availability of data stored in a plurality of sub-blocks of the physical data block;

in response to determining that there is the data state information, selecting a target sub-block from the plurality of sub-blocks of the physical storage block based on the data state information; and

providing the user with data stored in the target sub-block.