Solid state drive slc migration start and completion time test method and apparatus

Abstract

This application relates to a method, apparatus, computer device, and storage medium for testing the start and completion time of SLC migration of a solid-state drive (SSD). The method includes: performing a secure erase on the SSD under test to ensure its initial state is consistent; waiting for the temperature to stabilize and recording the initial temperature of the SSD under test; performing a sequential write operation on the SSD under test using FIO, writing a certain percentage of the total disk capacity and immediately recording the temperature upon completion; allowing the drive to stand still and recording the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the completion temperature, and the temperature stabilizes; modifying the percentage of the write volume and repeating the erasure and temperature recording steps; and determining the start and end times of the SLC migration based on the temperature changes recorded during the resting period. This invention can confirm whether SLC migration has occurred and the start and completion times of SLC migration, and is applicable to all SSDs conforming to standard protocols without additional hardware costs.

Description

Technical Field

[0001] This invention relates to the field of solid-state drive (SSD) testing technology, and in particular to a method, apparatus, computer device, and storage medium for testing the startup and completion time of SSD (Solid-State Drive) migration. Background Technology

[0002] SLC (Single Level Cache, 1 bit per cell) is fast and has a long lifespan, but its price is several times higher than NAND media such as MLC (Multi-Level Cell, 2 bits per cell), TLC (Trinary-Level Cell, 3 bits per cell), and QLC (Quad-level Cell, 4 bits per cell). Currently, mainstream consumer-grade SSDs use TLC media. Its write performance bandwidth is less than one-third that of SLC and its lifespan is short, but its advantages are low price and large capacity, so it has gradually become the mainstream SSD. To enable TLC-based SSDs to provide SLC-level performance during testing and use, and to meet the high bandwidth requirements of specific scenarios, various companies simulate an SLC layer on top of the TLC layer as an SLC cache. During user operation, the amount of data on the drive continuously increases, causing the available SLC cache size to continuously decrease. When the amount of data written exceeds the limit of the cache capacity, the write speed will drop significantly. When the host stops writing data to the solid-state drive, the solid-state drive will start moving the data in the SLC cache to the TLC cache. The cleanup of the SLC cache will restore the read and write performance to the performance of simulated SLC.

[0003] Currently, most methods for verifying SSD SLC cache performance involve testing the drive after it has been empty and filled to 50-90% capacity for a period of time. This method cannot pinpoint the exact start and completion times of SLC migration; it often relies on waiting a sufficiently long time to ensure completion. If the SLC cache is not fully released after a period of inactivity, it will lead to lower performance when writing data again. While firmware code could be used to add start and completion logs to output the SLC migration times, this method lacks universality and is unavailable for any SSD purchased online. Summary of the Invention

[0004] Therefore, it is necessary to provide a method, apparatus, computer equipment, and storage medium for testing the startup and completion time of SLC solid-state drive migration in response to the above-mentioned technical problems.

[0005] A method for testing the boot and completion times of SLC (Solid State Drive) migration, the method comprising:

[0006] Perform a secure erase on the solid-state drive under test to bring it back to its initial state.

[0007] After the temperature stabilizes, record the initial temperature of the solid-state drive under test;

[0008] FIO was used to sequentially write to the solid-state drive under test, with the amount of writing being a certain percentage of the total disk capacity, and the temperature at the time of completion was recorded immediately.

[0009] Let it stand still and record the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the temperature at the end and the temperature is stable;

[0010] Modify the percentage of the write volume and repeat the erase and temperature recording steps described above;

[0011] The start and end times of SLC transfer are determined by recording temperature changes during the settling period.

[0012] In one embodiment, the step of sequentially writing to the solid-state drive under test using FIO, writing a certain percentage of the total disk capacity, and immediately recording the temperature upon completion includes:

[0013] FIO was used to sequentially write to the solid-state drive under test, with the write volume being 10% of the total disk capacity, and the temperature at the time of completion was recorded immediately.

[0014] In one embodiment, the percentage of the write amount is modified and the erase and temperature recording steps described above are repeated:

[0015] The write percentages were changed sequentially to 20%, 30%, 50%, 70%, 90%, and 100%, and the erase and temperature recording steps were repeated.

[0016] In one embodiment, the step of determining the start and end times of SLC transfer based on the recorded temperature changes during the resting period includes:

[0017] If the recorded temperature maintains a positive increase over a certain continuous period of time, the initial moment of maintaining the positive increase is the time when the SLC transfer begins.

[0018] If the recorded temperature maintains a negative growth over a certain continuous period of time, the initial moment of maintaining the negative growth is the time when the SLC transfer ends.

[0019] A device for testing the startup and completion time of SLC (Solid State Drive) migration, the device comprising:

[0020] A secure erase module is used to securely erase the solid-state drive under test to ensure that the initial state of the solid-state drive under test is consistent.

[0021] The first recording module is used to record the initial temperature of the solid-state drive under test after the temperature has stabilized.

[0022] The disk filling test module is used to perform sequential write filling on the solid-state drive under test using FIO, with the write volume being a certain percentage of the total disk capacity and the temperature immediately recorded upon completion.

[0023] The second recording module is used to allow the temperature to stand still and record the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the temperature at the end and the temperature is stable.

[0024] A loop test module is used to modify the percentage of the write volume and repeatedly execute the above-mentioned erase and temperature recording steps;

[0025] The result judgment module is used to determine the start and end times of SLC transfer based on the temperature changes recorded during the resting period.

[0026] In one embodiment, the filling test module is further configured to:

[0027] FIO was used to sequentially write to the solid-state drive under test, with the write volume being 10% of the total disk capacity, and the temperature at the time of completion was recorded immediately.

[0028] In one embodiment, the loop test module is further configured to:

[0029] The write percentages were changed sequentially to 20%, 30%, 50%, 70%, 90%, and 100%, and the erase and temperature recording steps were repeated.

[0030] In one embodiment, the result determination module is further configured to:

[0031] If the recorded temperature maintains a positive increase over a certain continuous period of time, the initial moment of maintaining the positive increase is the time when the SLC transfer begins.

[0032] If the recorded temperature maintains a negative growth over a certain continuous period of time, the initial moment of maintaining the negative growth is the time when the SLC transfer ends.

[0033] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of any of the methods described above.

[0034] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the above methods.

[0035] The aforementioned method, apparatus, computer equipment, and storage medium for testing the start and completion time of SLC migration for solid-state drives (SSDs) involve: performing a secure erase on the SSD under test to ensure a consistent initial state; waiting for the temperature to stabilize and recording the initial temperature of the SSD; using FIO to sequentially write to the SSD, writing a certain percentage of the total disk capacity and immediately recording the temperature upon completion; allowing the drive to stand still and recording the temperature per second for a period until the recorded temperature is lower than the average of the initial and completion temperatures and stabilizes; modifying the percentage of the write volume and repeating the erasure and temperature recording steps; and determining the start and end times of SLC migration based on the temperature changes recorded during the resting period. This invention utilizes FIO to fill the disk under test with different proportions and then monitors the SMART temperature to confirm whether SLC migration has occurred and the start and completion of the migration. It is applicable to all SSDs conforming to standard protocols and incurs no additional hardware cost. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating a method for testing the startup and completion time of SLC disk transfer in one embodiment.

[0037] Figure 2 This is a flowchart illustrating the startup and completion time testing method for SLC solid-state drive migration in another embodiment.

[0038] Figure 3 This is a flowchart illustrating the startup and completion time testing method for SLC solid-state drive migration in another embodiment.

[0039] Figure 4 This is a schematic diagram of the test results for a product under test at a fill ratio of 20%.

[0040] Figure 5 This is a schematic diagram of the test results for a product under test at a fill ratio of 30%.

[0041] Figure 6 This is a schematic diagram showing the test results of another product under test at a fill ratio of 20%.

[0042] Figure 7 This is a schematic diagram showing the test results of another product under test at a fill ratio of 30%.

[0043] Figure 8 This is a structural block diagram of a device for testing the startup and completion time of SLC (Solid State Drive) migration in one embodiment.

[0044] Figure 9 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0046] Currently, most methods for verifying SSD SLC cache performance involve testing the drive after it has been empty and filled to 50-90% capacity for a period of time. This method cannot pinpoint the exact start and completion times of SLC migration; it often relies on waiting a sufficiently long time to ensure completion. If the SLC cache is not fully released after a period of inactivity, it will lead to lower performance when writing data again. While firmware code could be used to add start and completion logs to output the SLC migration times, this method lacks universality and is unavailable for any SSD purchased online.

[0047] Based on this, the present invention proposes a method for testing the start and completion time of SLC migration of solid-state drives, which aims to efficiently confirm whether SLC migration has occurred and the start and completion of SLC migration.

[0048] In one embodiment, such as Figure 1 As shown, a method for testing the startup and completion time of SLC solid-state drive migration is provided. The method includes:

[0049] Step 102: Perform a secure erase on the solid-state drive under test to ensure that the solid-state drive under test is in the same initial state as the solid-state drive under test.

[0050] Step 104: After the temperature stabilizes, record the initial temperature of the solid-state drive under test.

[0051] Step 106: Use FIO to perform sequential write to the solid-state drive under test, writing a certain percentage of the total disk capacity and immediately recording the temperature when it is completed.

[0052] Step 108: Let the temperature stand still and record the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the temperature at the end of the process and the temperature stabilizes.

[0053] Step 110: Modify the percentage of the write volume and repeat the erase and temperature recording steps described above;

[0054] Step 112: Determine the start and end times of SLC transfer based on the temperature changes recorded during the resting period.

[0055] In this embodiment, a method for testing the start and completion time of SLC migration of solid-state drives is proposed. This method is designed to test the start and completion time of SLC cache migration of solid-state drives. After filling the test disk with different proportions using FIO, the presence of SLC migration and the start and completion of SLC migration are confirmed by monitoring the SMART temperature. This method is applicable to all solid-state drives that comply with standard protocols.

[0056] Specifically, first, the disk is safely erased using the NVME format command as a slave drive to ensure the consistency of the disk's initial state. After the temperature stabilizes (the temperature difference is less than 2 for 5 consecutive seconds), the initial temperature of the solid-state drive under test is recorded.

[0057] Next, FIO was used to sequentially write to the solid-state drive under test, with the write volume being a certain percentage (10%) of the total disk capacity, and the temperature at the time of completion was recorded immediately. The drive was left to stand and the temperature was recorded every second for a period of time until the recorded temperature was lower than the average of the initial temperature and the temperature at the time of completion and the temperature stabilized (the temperature difference was less than 2 for 5 consecutive seconds).

[0058] Then, modify the percentage of the write volume (20%, 30%, 50%, 70%, 90%, 100%) and repeat the above erase and temperature recording steps; finally, determine the start and end times of SLC transfer based on the recorded temperature changes during the resting period.

[0059] In this embodiment, a secure erase is performed on the SSD under test to ensure its initial state is consistent. After the temperature stabilizes, the initial temperature of the SSD under test is recorded. A sequential write operation is performed on the SSD under test using FIO, with the write amount being a certain percentage of the total disk capacity, and the temperature at completion is immediately recorded. The disk is left to stand, and the temperature is recorded every second for a period of time until the recorded temperature is lower than the average of the initial temperature and the completion temperature, and the temperature stabilizes. The percentage of the write amount is modified, and the erase and temperature recording steps are repeated. The start and end times of SLC migration are determined based on the temperature changes recorded during the resting period. This solution utilizes FIO to fill the disk under test with different proportions, and then monitors the SMART temperature to confirm whether SLC migration has occurred and the start and completion of SLC migration. It is applicable to all SSDs conforming to standard protocols and incurs no additional hardware cost.

[0060] In one embodiment, the step of sequentially writing to the solid-state drive under test using FIO, writing a certain percentage of the total disk capacity, and immediately recording the temperature upon completion includes: sequentially writing to the solid-state drive under test using FIO, writing 10% of the total disk capacity, and immediately recording the temperature upon completion.

[0061] In one embodiment, the percentage of the write amount is modified and the erase and temperature recording steps described above are repeated: the write amount is modified sequentially to 20%, 30%, 50%, 70%, 90%, and 100%, and the erase and temperature recording steps described above are repeated.

[0062] In one embodiment, such as Figure 2 As shown, a method for testing the start and completion time of SLC transfer of a solid-state drive is provided. The method includes the following steps for determining the start and end times of SLC transfer based on temperature changes recorded during a resting period:

[0063] Step 202: When the recorded temperature maintains a positive increase for a certain continuous time, the initial moment of maintaining the positive increase is the time when the SLC transfer begins.

[0064] Step 204: When the recorded temperature maintains a negative growth over a certain continuous period of time, the initial moment of maintaining the negative growth is the time when the SLC transfer ends.

[0065] In one embodiment, a method for testing the startup and completion time of SLC hard drive migration is provided, and the test environment is as follows:

[0066] Hardware Requirements: The computer under test is an ASUS Z690. The specific model is not mandatory. In this embodiment, the ASUS Z690 is preferred. The solid-state drive (SSD) under test is a TLC SSD that supports simulated SLC caching. The testing method described herein is applicable to various multi-layer storage unit SSDs with simulated SLC. For ease of description, the most mainstream TLC SSD is used as the test and description object.

[0067] Software requirements: The operating system is Linux Red Hat; the testing tools are FIO (an open-source testing tool mainly used for stress testing and performance verification of hard drives) and smartmontools (an open-source tool for obtaining hard drive SMART information); the test scripts are self-written batch scripts; there are no strict requirements for the testing OS and tools, but Red Hat, FIO and smartmontools are preferred in this embodiment.

[0068] Specifically, refer to Figure 3 The diagram shows the test method for startup and completion time of SLC solid-state drive migration. The test process includes:

[0069] 1. Use the NVME format command to perform a secure erase on the disk as a slave disk to ensure the consistency of the disk's initial state.

[0070] 2. After the temperature stabilizes (the temperature difference is less than 2 for 5 consecutive seconds), record the solid-state drive temperature A read by SMART.

[0071] 3. Use FIO to perform a 128KB sequential write to the disk under test using Q32T1, with the write amount being 10% of the total disk capacity (X = 10%), and immediately record the temperature B when the write is completed.

[0072] 4. Let stand still, and collect the temperature C1, C2, C3...Cn per second for at least 60 seconds until Cn < (A+B) / 2 and the temperature stabilizes (the temperature difference for 5 consecutive seconds is less than 2).

[0073] 5. Repeat steps 1-4, modifying X to 20%, 30%, 50%, 70%, 90%, and 100% respectively.

[0074] 6. Determine the start and end times of SLC transfer based on the changes in Cn. The specific method for determining the start time of transfer is as follows: if the temperature increases positively for 5 consecutive seconds, Cn ≤ Cn+1 ≤ Cn+2 ≤ Cn+3 ≤ Cn+4, then n is the start time of transfer. The specific method for determining the end time of transfer is as follows: if the temperature increases negatively for 5 consecutive seconds, Cm > Cm+1 ≥ Cm+2 ≥ Cm+3 ≥ Cm+4, then m is the end time of transfer.

[0075] Specifically, the following table shows whether two products will undergo SLC relocation when the pad is 20% and 30% full, and the start and end times of the SLC relocation:

[0076]

[0077] In this embodiment, the start and completion times of SLC cache migration of solid-state drives can be tested quickly and efficiently. By filling the test disk with different proportions, the SMART temperature is monitored to confirm whether SLC migration has occurred and the start and completion times of SLC migration.

[0078] It should be understood that, although Figures 1-7 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figures 1-7 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0079] In one embodiment, such as Figure 8As shown, a solid-state drive (SLC) migration startup and completion time testing device 800 is provided, the device comprising:

[0080] A secure erase module 801 is used to securely erase the solid-state drive under test so that the initial state of the solid-state drive under test is consistent.

[0081] The first recording module 802 is used to record the initial temperature of the solid-state drive under test after waiting for the temperature to stabilize.

[0082] The disk filling test module 803 is used to perform sequential write filling on the solid-state drive under test using FIO, with the write amount being a certain percentage of the total disk capacity and the temperature immediately recorded upon completion.

[0083] The second recording module 804 is used to stand still and record the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the temperature at the end and the temperature is stable.

[0084] The cyclic test module 805 is used to modify the percentage of the write amount and repeatedly execute the above-mentioned erase and temperature recording steps;

[0085] Result judgment module 806 is used to determine the start and end times of SLC transfer based on the recorded temperature changes during the resting period.

[0086] In one embodiment, the filling test module 803 is further configured to:

[0087] FIO was used to sequentially write to the solid-state drive under test, with the write volume being 10% of the total disk capacity, and the temperature at the time of completion was recorded immediately.

[0088] In one embodiment, the loop test module 805 is further configured to:

[0089] The write percentages were changed sequentially to 20%, 30%, 50%, 70%, 90%, and 100%, and the erase and temperature recording steps were repeated.

[0090] In one embodiment, the result determination module 806 is further configured to:

[0091] If the recorded temperature maintains a positive increase over a certain continuous period of time, the initial moment of maintaining the positive increase is the time when the SLC transfer begins.

[0092] If the recorded temperature maintains a negative growth over a certain continuous period of time, the initial moment of maintaining the negative growth is the time when the SLC transfer ends.

[0093] For specific limitations on the test apparatus for the startup and completion time of SLC SSD migration, please refer to the limitations on the test method for startup and completion time of SLC SSD migration mentioned above, which will not be repeated here.

[0094] In one embodiment, a computer device is provided, the internal structure of which can be shown as follows: Figure 9 As shown, the computer device includes a processor, memory, and a network interface connected via a device bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores operating devices, computer programs, and a database. The internal memory provides an environment for the operation of the operating devices and computer programs stored in the non-volatile storage medium. The network interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a method for testing the boot and completion times of SLC (Solid State Drive) relocation.

[0095] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0096] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps in the various method embodiments described above.

[0097] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the various method embodiments described above.

[0098] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0099] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0100] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for testing the startup and completion time of SLC transfer of a solid-state drive, the method comprising: Perform a secure erase on the solid-state drive under test to bring it back to its initial state. After the temperature stabilizes, record the initial temperature of the solid-state drive under test; FIO was used to sequentially write to the solid-state drive under test, with the amount of writing being a certain percentage of the total disk capacity, and the temperature at the time of completion was recorded immediately. Let it stand still and record the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the temperature at the end and the temperature is stable; Modify the percentage of the write volume and repeat the erase and temperature recording steps described above; The start and end times of SLC transfer are determined by recording temperature changes during the settling period. The steps for determining the start and end times of SLC transfer based on temperature changes recorded during the resting period include: If the recorded temperature maintains a positive increase over a certain continuous period of time, the initial moment of maintaining the positive increase is the time when the SLC transfer begins. If the recorded temperature maintains a negative growth over a certain continuous period of time, the initial moment of maintaining the negative growth is the time when the SLC transfer ends.

2. The method of claim 1, wherein, The steps of sequentially writing to the solid-state drive under test using FIO, writing a certain percentage of the total disk capacity, and immediately recording the temperature upon completion include: FIO was used to sequentially write to the solid-state drive under test, with the write volume being 10% of the total disk capacity, and the temperature at the time of completion was recorded immediately.

3. The method for testing the startup and completion time of SLC transfer of a solid-state drive according to claim 2, characterized in that, The percentage of the write amount is modified, and the erase and temperature recording steps described above are repeated: The write percentages were changed sequentially to 20%, 30%, 50%, 70%, 90%, and 100%, and the erase and temperature recording steps were repeated.

4. A device for testing the startup and completion time of SLC hard drive migration, characterized in that, The device includes: A secure erase module is used to securely erase the solid-state drive under test to ensure that the initial state of the solid-state drive under test is consistent. The first recording module is used to record the initial temperature of the solid-state drive under test after the temperature has stabilized. The disk filling test module is used to perform sequential write filling on the solid-state drive under test using FIO, with the write volume being a certain percentage of the total disk capacity and the temperature immediately recorded upon completion. The second recording module is used to allow the temperature to stand still and record the temperature per second for a period of time until the recorded temperature is less than the average of the initial temperature and the temperature at the end and the temperature is stable. A loop test module is used to modify the percentage of the write volume and repeatedly execute the above-mentioned erase and temperature recording steps; The result judgment module is used to determine the start and end times of SLC transfer based on the temperature changes recorded during the resting period. The result judgment module is also used for: If the recorded temperature maintains a positive increase over a certain continuous period of time, the initial moment of maintaining the positive increase is the time when the SLC transfer begins. If the recorded temperature maintains a negative growth over a certain continuous period of time, the initial moment of maintaining the negative growth is the time when the SLC transfer ends.

5. The device for testing the startup and completion time of SLC transfer of a solid-state drive according to claim 4, characterized in that, The filling test module is also used for: FIO was used to sequentially write to the solid-state drive under test, with the write volume being 10% of the total disk capacity, and the temperature at the time of completion was recorded immediately.

6. The device for testing the startup and completion time of SLC solid-state drive migration according to claim 5, characterized in that, The loop test module is also used for: The write percentages were changed sequentially to 20%, 30%, 50%, 70%, 90%, and 100%, and the erase and temperature recording steps were repeated.

7. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 3.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 3.

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