Error detection and recovery method and device for data in memory area of hot backup computer

Abstract

The invention discloses a hot backup computer memory area data error detection and recovery method and device, and belongs to the field of memory data error detection and recovery. The method comprises the following steps: partitioning a memory area of each single machine, wherein the partitioning results of the single machines are the same; aiming at each control period, executing the following steps: calculating a mark value of each memory block based on the public data; comparing the mark values of the memory blocks at the same position of each single machine so as to determine the fault memory block of each single machine based on whether the mark values are consistent or not; if the fault memory blocks exist, whether public data recovery converges or not is judged on the basis of a plurality of historical control periods adjacent to the current control period and the number of the fault memory blocks of the current control period, so that a recovery strategy is determined. According to the scheme, a public data memory partition block marking comparison mode is utilized, the memory partition blocks with wrong public data can be quickly identified and positioned, data recovery can be quickly performed, and large-range diffusion of faults can be effectively prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of memory data error detection and recovery, and in particular to a method and device for detecting and recovering the error of the memory area data of a hot backup computer. Background Art

[0002] High-reliability computers usually back up multiple identical machines. These machines receive and process information at the same time. The result data is output after voting and can correct errors in real time, so they have extremely high reliability. In order to output and work to achieve the hot backup capability, the machines in the hot backup computer need to exchange and compare internal data within a fixed period, including receiving data, sending data, intermediate calculation results, etc. Therefore, the hot backup computer has a high tolerance for data errors in the internal storage area of ​​the machine, but it is precisely because of this that the errors in the storage area data of the hot backup computer are highly hidden, resulting in a lag in the identification of the faulty machine, and the fault may spread during the lag period, which brings great difficulties to the fault location and recovery after fault identification. Even the data errors in the storage area may have spread widely and the fault cannot be recovered.

[0003] Therefore, there is an urgent need to provide a fast error detection and recovery method for hot backup computer memory area data, which can detect and recover the erroneous data in the data storage area before it spreads. Summary of the invention

[0004] The present invention provides a method for detecting and recovering the data in the memory area of ​​a hot backup computer, which can solve the problem that the error recognition of the data in the memory area of ​​the hot backup computer is delayed, which easily leads to the spread of the fault and brings great difficulties to the location and recovery of the fault. The technical solution is as follows:

[0005] On the one hand, a method for detecting and recovering errors in a hot backup computer memory area is provided, the method comprising:

[0006] The memory area of ​​each stand-alone machine is divided into blocks, and the block division results of each stand-alone machine are the same;

[0007] For each control cycle, the following are executed:

[0008] Based on the public data of each memory block, calculate the tag value of each memory block;

[0009] Compare the tag values ​​of the memory blocks at the same position of each single machine to determine the faulty memory block of each single machine based on whether the tag values ​​are consistent;

[0010] If there is a faulty memory block, whether the public data recovery is converged is determined based on several historical control cycles adjacent to the current control cycle and the number of faulty memory blocks in the current control cycle, so as to determine a recovery strategy based on the determination result.

[0011] On the other hand, a device for detecting and recovering errors in a hot backup computer memory area is provided, the device comprising:

[0012] The block division unit is used to divide the memory area of ​​each single machine into blocks, and the block division results of each single machine are the same;

[0013] The marking unit is used to perform, for each control cycle: calculating a marking value of each memory block based on the public data of each memory block;

[0014] A detection unit, used to compare the tag values ​​between the memory blocks at the same position of each single machine, so as to determine the faulty memory block of each single machine based on whether the tag values ​​are consistent;

[0015] The recovery unit is used to determine whether the public data recovery converges based on the number of historical control cycles adjacent to the current control cycle and the number of faulty memory blocks in the current control cycle if there is a faulty memory block, so as to determine the recovery strategy based on the judgment result.

[0016] On the other hand, a computer device is provided, which includes a memory and a processor, wherein the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory to implement the steps of the above-mentioned method.

[0017] On the other hand, a computer-readable storage medium is provided, wherein a computer program is stored in the storage medium, and when the computer program is executed by a processor, the steps of the above-mentioned method are implemented.

[0018] On the other hand, a computer program product is provided, comprising a computer program, wherein the computer program implements the steps of the above method when executed by a processor.

[0019] The technical solution provided by the present invention can at least bring the following beneficial effects:

[0020] Dividing the memory area of ​​each hot standby machine into blocks can make fault location more accurate and improve the recovery speed. Combined with the tag value comparison method, the error detection speed can be improved. In addition, the number of faulty memory blocks in the historical control cycle and the current control cycle is used to determine whether the public data recovery has converged, and to formulate a recovery strategy, which can effectively prevent the fault from spreading on a large scale. Therefore, this solution uses the public data memory area block tag comparison method to quickly identify and locate the public data erroneous memory blocks and quickly perform data recovery, and can effectively prevent the fault from spreading on a large scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a flow chart of an error detection and recovery method for hot backup computer memory area data provided by one embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of a flow chart provided by an embodiment of the present invention;

[0024] Figure 3 It is a structural diagram of an error detection and recovery device for hot backup computer memory area data provided by one embodiment of the present invention;

[0025] Figure 4 It is a hardware architecture diagram of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] The specific implementation of the above concept is described below.

[0028] Please refer to Figure 1 , an embodiment of the present invention provides a method for detecting and recovering errors in a hot backup computer memory area, the method comprising:

[0029] Step 100, dividing the memory area of ​​each stand-alone machine into blocks, and the block division results of each stand-alone machine are the same;

[0030] Step 102, for each control cycle, is performed: based on the public data of each memory block, calculating the tag value of each memory block;

[0031] Step 104, comparing the tag values ​​of the memory blocks at the same position of each single machine, so as to determine the faulty memory block of each single machine based on whether the tag values ​​are consistent;

[0032] Step 106 , if there is a faulty memory block, judging whether the public data recovery is converged based on the number of faulty memory blocks in several historical control cycles adjacent to the current control cycle and the current control cycle, so as to determine the recovery strategy based on the judgment result.

[0033] In the embodiment of the present invention, the memory area of ​​each hot standby machine is divided into blocks, which can make fault location more accurate and improve the recovery speed. In combination with the tag value comparison method, the error detection speed can be improved. In addition, the number of faulty memory blocks in the historical control cycle and the current control cycle is used to determine whether the public data recovery has converged, and to formulate a recovery strategy, which can effectively prevent the fault from spreading on a large scale. Therefore, this solution uses the public data memory area block tag comparison method to quickly identify and locate the public data erroneous memory blocks and quickly perform data recovery, and can effectively prevent the fault from spreading on a large scale.

[0034] Described below Figure 1 How the various steps are performed.

[0035] For step 100:

[0036] In the embodiment of the present invention, the memory area data of each stand-alone computer of the hot standby computer is divided into private data and public data, wherein the public data is related to the system function calculation of the control computer, and the private data is not related to the system function calculation of the control computer. Under normal circumstances, the public data in the memory area of ​​each stand-alone computer of the hot standby computer is completely synchronized and identical. Under abnormal circumstances, part of the public data of a stand-alone computer is not synchronized with other stand-alone computers. Only by restoring the unsynchronized data before the normal calculation task of the current control cycle or the next control cycle can the faulty stand-alone computer be restored.

[0037] For example, there are two stand-alone machines, and the memory partition results of the two stand-alone machines need to be the same. Assuming that stand-alone 1 is divided into three memory blocks, then stand-alone 2 needs to be partitioned in the same way according to the address space corresponding to each memory block of stand-alone 1, that is, stand-alone 2 is also divided into three memory blocks, and each memory block of stand-alone 1 has a one-to-one correspondence with each memory block of stand-alone 2.

[0038] In some implementations, the memory block sizes of a single machine are non-uniform.

[0039] In this embodiment, the division of memory blocks is not necessarily of fixed size. It can be comprehensively considered in combination with the probability of data being rewritten, the importance of the data area, and the computing resources. When the probability of data being rewritten is high and the data is important, the memory blocks can be made smaller and denser, so that faulty data can be located more accurately and quickly.

[0040] For steps 102 and 104:

[0041] It should be noted that a single machine executes a normal task once in each control cycle. In a normal task, a certain memory block of all single machines may be rewritten synchronously. This is required by normal tasks. When the tag values ​​of memory blocks at the same position between single machines are inconsistent, it means that the public data of the memory block is wrong and needs to be restored.

[0042] In some implementations, the tag value is the cumulative sum of the public data of the memory partition.

[0043] It can be understood that the tag value can be the ECC (Error Correction Code) of the memory block partition or the parity check value. However, the ECC calculation will take a lot of time, and the tag value will also occupy more storage resources, resulting in large resource consumption. Although the parity check value is relatively simple to calculate and takes up less time and resources, when a two-bit error occurs in the memory partition, the soft fault will not be recognized. Therefore, this embodiment uses the cumulative sum as the tag value, which will not cause a large amount of time and resources to be consumed, and can avoid the situation where the fault cannot be recognized.

[0044] After obtaining the tag value of each memory block of each single machine, the tag values ​​of the memory blocks at the same position of each single machine are compared. For example, the tag values ​​of memory block 1 of single machine 1, memory block 1 of single machine 2, and memory block 1 of single machine 3 are compared. If they are consistent, it means that the memory blocks 1 of the three single machines are not faulty and do not need to be restored. If the tag value of the memory block 1 of single machine 1 is inconsistent with that of the other two single machines, it is determined that memory block 1 of single machine 1 is not a faulty memory machine, so as to obtain the faulty memory blocks of each single machine in each control cycle.

[0045] Regarding step 106:

[0046] You can refer to Figure 2 Flow chart of the process, if there is no faulty memory block in the current control cycle, then no data recovery is performed in the current control cycle, and only the original normal task is executed.

[0047] When there are many faulty memory blocks, if only the idle time of the current control cycle is used to exchange and recover the faulty memory block data, one control cycle may not be completed and multiple control cycles may be required to complete it. However, when the recovery is not completed, the normal tasks in the control cycle may use the unrecovered erroneous data, which may cause the fault to spread, so that the number of faulty memory blocks in the next control cycle increases compared with the previous control cycle, that is, the public data recovery has not converged (the speed of data recovery is lower than the speed of data rewriting). In this case, the recovery strategy needs to be adjusted to give priority to public data recovery.

[0048] In some implementations, step 106 may include:

[0049] Count the amount of public data of all faulty memory blocks in the current control cycle, and determine the number of cycles P required for data recovery based on the amount of data, the idle time of the current control cycle, and the switching bandwidth of a single machine;

[0050] In several historical control cycles adjacent to the current control cycle and the current control cycle, if the number of faulty memory blocks does not increase, it is determined that the public data recovery can converge, and the recovery strategy is to use the faulty memory blocks to perform data recovery in the normal memory blocks corresponding to other single machines during the idle time of P control cycles;

[0051] In several historical control cycles adjacent to the current control cycle and the current control cycle, if the number of faulty memory blocks increases, it is determined that public data recovery cannot converge, and a recovery strategy is determined based on the cycle number P and the safety priority of the faulty memory blocks in the current control cycle.

[0052] In the embodiment of the present invention, the number of cycles P required for data recovery is calculated by the following formula:

[0053]

[0054] In the formula, N is the amount of data, D is the switching bandwidth of a single machine, and T x It is the idle time of the current control cycle.

[0055] It can be understood that the original idle time and the exchange bandwidth of a single machine can be determined in advance. Under normal circumstances, it should not affect the progress of normal tasks, and public data recovery is only performed during idle time.

[0056] For example, if the number of faulty memory blocks in the first two historical control cycles adjacent to the current control cycle is 2 and 2 respectively, and the number of faulty memory blocks in the current control cycle is 2, then it can be determined that the current public data recovery can converge, and the recovery strategy is to use the faulty memory blocks in the normal memory blocks corresponding to other single machines to perform data recovery during the idle time of the P control cycles calculated above. It can be understood that steps 102-106 need to be re-executed for each control cycle, that is, the recovery strategy needs to be re-determined for each control cycle.

[0057] In the previous two historical control cycles adjacent to the current control cycle, the number of faulty memory blocks is 2 and 3 respectively, while the number of faulty memory blocks in the current control cycle is 4. It can be determined that the current public data recovery cannot converge, and the recovery strategy can be determined based on the security priority of the faulty memory block and the number of cycles P. Instead of reducing the normal exchange task time as long as it is considered not to converge, because the security priority of the public data of some faulty memory blocks is not high, the usage rate is low, and there is no need to affect the normal exchange task.

[0058] In some implementations, a recovery strategy is determined based on the cycle number P and the safety priority of the faulty memory partition of the current control cycle, including:

[0059] When the number of cycles P is equal to 1, the recovery strategy is determined to perform data recovery using the normal memory block corresponding to the faulty memory block during the idle time of the current control cycle;

[0060] When the number of cycles P is greater than 1, it is determined whether the total value of the safety priority of the fault memory block in the current control cycle is greater than the threshold;

[0061] If it is not greater than, the recovery strategy is to use the normal memory block corresponding to the faulty memory block to recover data during the idle time of P control cycles;

[0062] If it is greater, the recovery strategy is determined to increase the idle time of the current control cycle so as to use the normal memory blocks corresponding to the faulty memory blocks to perform data recovery first.

[0063] In this embodiment, if the cycle number P is equal to 1, it means that although the number of faulty memory blocks has increased, data recovery can still be completed by utilizing the idle time of the current control cycle. Therefore, there is no need to reduce the normal exchange task time to increase the idle time to prioritize data recovery.

[0064] If the number of cycles P is greater than 1, the recovery strategy can be determined according to the security priority. For faulty memory blocks with high security priority, the strategy of reducing the normal exchange task time and giving priority to data alignment and recovery is adopted; for faulty memory blocks with low security priority, it is considered that the faulty memory blocks have a certain degree of fault tolerance, and data exchange and recovery are carried out during the idle time of the normal exchange task. The faulty memory blocks are overwritten. Although convergence cannot be achieved, the further spread of faulty data can still be effectively suppressed.

[0065] It can be understood that since the recovery strategy will be re-determined for each control cycle, even if the recovery strategy is to increase the idle time of the current control cycle, regardless of whether the recovery is completed after the increase, the original idle time will be restored in the next control cycle. Only when the cycle number P is greater than 1 and it is judged that the total security priority value of the faulty memory block in the next control cycle is greater than the threshold, the idle time of the next control cycle will be increased for data recovery.

[0066] Please refer to Figure 3 The embodiment of the present invention provides an error detection and recovery device for hot backup computer memory area data, the device comprising:

[0067] The block division unit 301 is used to divide the memory area of ​​each stand-alone machine into blocks, and the block division results of each stand-alone machine are the same;

[0068] The marking unit 302 is used to perform, for each control cycle: calculating a marking value of each memory block based on the public data of each memory block;

[0069] The detection unit 303 is used to compare the tag values ​​between the memory blocks at the same position of each single machine, so as to determine the faulty memory block of each single machine based on whether the tag values ​​are consistent;

[0070] The recovery unit 304 is used to determine whether the public data recovery converges based on the number of historical control cycles adjacent to the current control cycle and the number of faulty memory blocks in the current control cycle if there is a faulty memory block, so as to determine the recovery strategy based on the judgment result.

[0071] In one embodiment of the present invention, the sizes of the memory blocks of a single machine in the block unit 301 are non-uniform.

[0072] In one embodiment of the present invention, the tag value in the tag unit 302 is the accumulated sum of the public data of the memory blocks.

[0073] In one embodiment of the present invention, the recovery unit 304 is used to perform:

[0074] Count the amount of public data of all faulty memory blocks in the current control cycle, and determine the number of cycles P required for data recovery based on the amount of data, the idle time of the current control cycle, and the switching bandwidth of a single machine;

[0075] In several historical control cycles adjacent to the current control cycle and the current control cycle, if the number of faulty memory blocks does not increase, it is determined that the public data recovery can converge, and the recovery strategy is to use the faulty memory blocks to perform data recovery in the normal memory blocks corresponding to other single machines during the idle time of P control cycles;

[0076] In several historical control cycles adjacent to the current control cycle and the current control cycle, if the number of faulty memory blocks increases, it is determined that public data recovery cannot converge, and a recovery strategy is determined based on the cycle number P and the safety priority of the faulty memory blocks in the current control cycle.

[0077] In one embodiment of the present invention, when the recovery unit 304 determines the recovery strategy based on the cycle number P and the safety priority of the faulty memory block of the current control cycle, it is used to:

[0078] When the number of cycles P is equal to 1, the recovery strategy is determined to perform data recovery using the normal memory block corresponding to the faulty memory block during the idle time of the current control cycle;

[0079] When the number of cycles P is greater than 1, it is determined whether the total value of the safety priority of the fault memory block in the current control cycle is greater than the threshold;

[0080] If it is not greater than, the recovery strategy is to use the normal memory block corresponding to the faulty memory block to recover data during the idle time of P control cycles;

[0081] If it is greater, the recovery strategy is determined to increase the idle time of the current control cycle so as to use the normal memory blocks corresponding to the faulty memory blocks to perform data recovery first.

[0082] In one embodiment of the present invention, the number of cycles P required for data recovery in the recovery unit 304 is calculated by the following formula:

[0083]

[0084] In the formula, N is the amount of data, D is the switching bandwidth of a single machine, and T x It is the idle time of the current control cycle.

[0085] It should be noted that the error detection and recovery device for hot backup computer memory area data provided in the above embodiment is only illustrated by the division of the above functional units. In actual application, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional units to complete all or part of the functions described above. In addition, the above device embodiment and the method embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0086] The embodiment of the present application also provides a computer device, please refer to Figure 3The computer device includes a processor and a memory, in which at least one instruction, at least one program, code set or instruction set is stored, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement the error detection and recovery method of the hot backup computer memory area data provided by the above-mentioned method embodiments.

[0087] An embodiment of the present application also provides a computer-readable storage medium, on which is stored at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor to implement the error detection and recovery method for hot backup computer memory area data provided in the above-mentioned method embodiments.

[0088] An embodiment of the present application also provides a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium, and the processor executes the computer program, so that the computer device executes the error detection and recovery method for hot backup computer memory area data described in any of the above embodiments.

[0089] For the convenience of description, the above system or device is described by dividing it into various modules or units according to its functions. Of course, when implementing the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0090] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly contributed to the prior art in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present application or certain parts of the embodiments.

[0091] Finally, it should be noted that, in this article, relational terms such as first, second, third and fourth are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0092] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for detecting and recovering errors in a hot backup computer memory area, characterized in that: The method comprises: The memory area of ​​each stand-alone machine is divided into blocks, and the block division results of each stand-alone machine are the same; For each control cycle, the following are executed: Based on the public data of each memory block, calculate the tag value of each memory block; Compare the tag values ​​of the memory blocks at the same position of each single machine to determine the faulty memory block of each single machine based on whether the tag values ​​are consistent; If there is a faulty memory block, whether the public data recovery is converged is determined based on several historical control cycles adjacent to the current control cycle and the number of faulty memory blocks in the current control cycle, so as to determine a recovery strategy based on the determination result.

2. The method according to claim 1, characterized in that The sizes of the memory blocks of the single machine are non-uniform.

3. The method according to claim 1, characterized in that The tag value is the cumulative sum of the public data of the memory block.

4. The method according to claim 1, characterized in that The method of judging whether the public data recovery is convergent based on a number of historical control cycles adjacent to the current control cycle and the number of faulty memory blocks in the current control cycle, and determining a recovery strategy based on the judgment result, includes: Counting the amount of public data of all faulty memory blocks in the current control cycle, and determining the number of cycles P required for data recovery based on the amount of data, the idle time of the current control cycle, and the switching bandwidth of a single machine; In several historical control cycles adjacent to the current control cycle and the current control cycle, if the number of faulty memory blocks does not increase, it is determined that the public data recovery can converge, and the recovery strategy is to use the faulty memory blocks to perform data recovery in the normal memory blocks corresponding to other single machines during the idle time of P control cycles; In several historical control cycles adjacent to the current control cycle and the current control cycle, if the number of faulty memory blocks increases, it is determined that public data recovery cannot converge, and a recovery strategy is determined based on the cycle number P and the safety priority of the faulty memory blocks in the current control cycle.

5. The method according to claim 4, characterized in that The recovery strategy is determined based on the number of cycles P and the safety priority of the faulty memory block of the current control cycle, including: When the number of cycles P is equal to 1, the recovery strategy is determined to perform data recovery using the normal memory block corresponding to the faulty memory block during the idle time of the current control cycle; When the cycle number P is greater than 1, it is determined whether the total value of the safety priority of the fault memory block in the current control cycle is greater than a threshold; If it is not greater than, the recovery strategy is to use the normal memory block corresponding to the faulty memory block to recover data during the idle time of P control cycles; If it is greater, the recovery strategy is determined to increase the idle time of the current control cycle so as to use the normal memory blocks corresponding to the faulty memory blocks to perform data recovery first.

6. The method according to claim 4 or 5, characterized in that The number of cycles P required for data recovery is calculated by the following formula: Where N is the amount of data, D is the switching bandwidth of a single machine, and T x It is the idle time of the current control cycle.

7. An error detection and recovery device for hot backup computer memory area data, characterized in that: The device comprises: The block division unit is used to divide the memory area of ​​each single machine into blocks, and the block division results of each single machine are the same; The marking unit is used to perform, for each control cycle: calculating a marking value of each memory block based on the public data of each memory block; A detection unit, used to compare the tag values ​​between the memory blocks at the same position of each single machine, so as to determine the faulty memory block of each single machine based on whether the tag values ​​are consistent; The recovery unit is used to determine whether the public data recovery converges based on the number of historical control cycles adjacent to the current control cycle and the number of faulty memory blocks in the current control cycle if there is a faulty memory block, so as to determine the recovery strategy based on the judgment result.

8. A computer device, characterized in that: The computer device includes a memory and a processor, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory to implement the steps of any one of the methods described in claims 1-6.

9. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The method comprises a computer program, wherein when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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