JPH07146810A - Computer system - Google Patents

Abstract

PURPOSE:To efficiently perform the matching processing of a data file even when a transmitter with comparatively slow data transfer speed and to remarkably reduce initialization processing time when a computer whose operation is being stopped is initialized. CONSTITUTION:In a computer system in which the matching processing of the data file is performed by performing data transmission mutually via the transmitter between first and second computers 1A, 1B provided with the same data files 2A, 2B individually and connected to each other by the transmitter, the data files 2A, 2B are divided into plural blocks, respectively, and difference is detected by comparing the cyclic check codes 3A. 3B of the data files 2A, 2B at every block, and consequently, data with only blocks with difference is transmitted via the transmitter.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data file by transmitting data via a transmission device between a plurality of computers each having the same data file and connected to each other by a transmission device. The present invention relates to a computer system that performs a matching process, and more particularly to a computer system that efficiently performs a data file matching process and can significantly reduce the initialization process time when a stopped computer is initialized.

[0002]

2. Description of the Related Art Generally, in a computer system having a plurality of computers each having the same data file and connected to each other by a transmission device, the contents of the data file which each computer has are A so-called data file matching process (consistency of the same data) is performed so that the data is always matched by being transmitted through the transmission device.

That is, when the content of a data file is changed in one computer, the data of the changed data file is notified to another computer via the transmission device, and the data of the data file in each computer is changed. I try to maintain consistency.

Further, when the contents of the data file are changed by one computer, and there is a computer that is stopped, the data changed during this stop is reflected on the computer. It will be left unattended. And
In this case, when the stopped computer is initialized, the data in the data file of its own computer is updated with the latest data from another computer.

In this case, when the contents of the data file are changed in one computer and the stopped computer is initialized, the number and size of data files for managing the consistency with other computers are If it is relatively small, the data update time of the data file is not a big problem.

However, if there are a large number of data files that require matching processing or if the size is relatively large, the data transmission time will increase accordingly, and thus the matching processing of the data files will take a long time. As a result, the initialization processing time of the computer becomes long.

On the other hand, in order to shorten the data transmission time, it is possible to use a transmission device having a relatively high data transmission rate as a transmission device. In this case, however, the computer system is expensive accordingly. It becomes a thing.

[0008]

As described above, in the conventional computer system, since it takes a long time to perform the data file matching processing, the initialization processing time becomes long when the stopped computer is initialized. There was a problem.

An object of the present invention is to efficiently perform data file matching processing even when a transmission device having a relatively low data transmission rate is used, and the initialization processing time when the stopped computer is initialized. It is to provide an extremely reliable computer system capable of significantly reducing the cost.

[0010]

In order to achieve the above object, according to the present invention, a transmission device is provided between a first computer and a second computer that individually have the same data file and are connected to each other by the transmission device. In a computer system that performs data file matching processing by transmitting data through each other, each data file is divided into a plurality of blocks, and when the second computer initializes the data in the second computer, A means for creating a cyclic check code for each block of the file and transmitting the cyclic check code to the first computer through a transmission device, and a cyclic check for each block of the data file in the first computer A means for creating a code, data of the cyclic check code created by the first computer, and Means for comparing the cyclic check code data transmitted from the computer in sequence for each block, and when a difference is detected in the cyclic check code data as a result of the comparison, the first computer Based on the means for transmitting the data of the corresponding block of the data file to the second computer via the transmission device, and the data of the corresponding block of the data file of the second computer based on the block data transmitted from the first computer. And means for updating.

[0011]

Therefore, in the computer system of the present invention,
When performing the matching process of each data file of the first and second computers, instead of transmitting all the data of the data file through the transmission device, each data file for which data matching is attempted is performed by a plurality of data files. Divide into blocks and detect the difference by comparing the cyclic check codes for each block of each data file.If there is a difference as a result, only the data of the corresponding block of the data file is transferred to the transmission device. By transmitting via data, unnecessary data transmission does not occur as much as in the case of a data file with high data equality, so it is possible to significantly reduce the time for data file matching processing, This significantly increases the initialization processing time when the stopped computer (second computer) is initialized. It is possible to shrinkage.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, not all the data in a data file is transmitted through a transmission device, but each data file for which data matching is to be performed is divided into a plurality of blocks, and each data file The difference is detected by comparing cyclic check codes (hereinafter referred to as CRC) for each block, and as a result, data of only the block having the difference is transmitted through the transmission device.

As a result, unnecessary data transmission does not occur as much as in the case of a data file having a high data equality,
The time required for the data file matching process is greatly shortened.

An embodiment of the present invention based on the above concept will be described below in detail with reference to the drawings.
FIG. 1 is a block diagram showing an example of the overall configuration of a computer system according to the present invention. It should be noted that, here, as the computer system, a case of a computer system including two computers will be described as an example.

In FIG. 1, the first computer 1A and the second computer 1B individually have the same data file 2A and data file 2B whose data contents should be the same value, and are transmitted. Devices are connected to each other.

The data file 2A and the data file 2B are each divided into a plurality of blocks as shown. On the other hand, when the second computer 1B itself initializes, it creates a CRC3B for each block of the data file 2B in the second computer 1B, and transmits this CRC3B to the first computer 1A. It has a function to transmit through.

When the CRC 3B is transmitted from the second computer 1B to the first computer 1A, the first computer 1A
A function of creating a CRC3A for each block of the data file 2A in A, a function of sequentially comparing the created data of the CRC3A and the data of the CRC3B transmitted from the second computer 1B for each block, As a result of this comparison, when a difference is detected in the data of CRC3A and CRC3B, it is determined that the data of the corresponding block is different between the data files 2A and 2B, and the first computer 1
The data of the corresponding block of the data file 2A of A
And the function to transmit to the computer 1B of
The above process is repeated until there is no difference between the data of C3A and CRC3B, and CRC3A and CRC3B
When the comparison of the data of all the blocks has been completed, a function of notifying the end of transmission to the second computer 1B via the transmission device is provided.

Further, the second computer 1B updates the data of the corresponding block of the data file 2B of the second computer 1B based on the block data transmitted from the first computer 1A, and sends an affirmative response. It also has a function of returning to the first computer 1A via a transmission device.

In the above, CRC3A and C3
The RC3B creates a 16-bit CRC for each block of the data file 2A of the first computer 1A, and C
It is assumed that the RC3B creates a 16-bit CRC for each block of the data file 2B of the second computer 1B.

More specifically, the CRC 3A and the CRC 3B are obtained by compressing and replacing the data of blocks of the data file 2A and the data file 2B, for example, as numerical values.

Next, the data file matching process in the computer system of the present embodiment having the above-mentioned configuration will be described with reference to the flow chart shown in FIG. Note that, here, the case where the content of the data file 2B of the second computer 1B is set to the same value as the content of the data file 2A of the first computer 1A (when the second computer 1B is initialized) will be described.

When the second computer 1B, which has been stopped, is initialized, first, in the second computer 1B, the data in the data file 2B in the computer 1B becomes the first data.
A 16-bit CRC 3B for each block of the data file 2B is created to check whether or not the data matches the data of the data file 2A in the computer 1A (S1). Then, the 16-bit CRC 3B for each block of the data file 2B created by the second computer 1B
Are transmitted to the first computer 1A via the transmission device (S
2).

On the other hand, the first computer 1A creates a 16-bit CRC3A for each block of the data file 2A, triggered by the transmission of the CRC3B from the second computer 1B (S3).

Further, in the first computer 1A, the computer 1A
16-bit CRC3A for each block of the data file 2A created in 1. and 16-bit CRC3 for each block of the data file 2B transmitted from the second computer 1B
The data of each CRC with B are sequentially compared for each block (S4).

As a result of this comparison, CRC3A and C
When a difference between RC3B and RC3B is detected, the data of the corresponding block is the data file 2A and data file 2
B is determined to be different, and the data of the corresponding block of the data file 2A is transmitted to the second computer 1B via the transmission device (S5).

On the other hand, in the second computer 1B, the data of the corresponding block of the data file 2B is updated by the block data of the data file 2A transmitted from the first computer 1A, and an affirmative response is sent to the first computer 1A. To the transmission device (S6).

Thereafter, until there is no difference between the CRC3A and the CRC3B, the above-mentioned S4,
The process of S5 is performed again in the second computer 1B.
The processing of 6 is repeated (S7).

As described above, the first computer 1A compares the data of CRC3A and CRC3B by the process S4, and when the data of all the blocks of CRC3A and CRC3B have been compared, the transmission termination is completed by the second computer. 1B is notified via the transmission device (S8).

As a result, the second computer 1 which has been stopped
The content of the data file 2B of B is set to the same value as the content of the data file 2A of the first computer 1A, and the matching processing of the data file 2A and the data file 2B is performed.

As described above, in this embodiment, the first and second computers 1A and 1B, which individually have the same data files 2A and 2B and are connected to each other by the transmission device, are connected via the transmission device. In a computer system that performs matching processing of the data files 2A and 2B by transmitting data to each other, each data file 2A and 2B is divided into a plurality of blocks, and the second computer 1B initializes itself. Sometimes, a 16-bit CRC3B for each block of the data file 2B in the second computer 1B is created, and this CRC3
B has a function of transmitting B to the first computer 1A via a transmission device, and the first computer 1A includes a second computer 1B.
When the CRC3B is transmitted, the 16-bit CRC for each block of the data file 2A in the first computer 1A
3A, a function of sequentially comparing the created CRC3A data and the CRC3B data transmitted from the second computer 1B for each block, and the result of this comparison, the CRC3A and CRC3B data When a difference is detected in the data block, it is determined that the data of the corresponding block is different between the data files 2A and 2B, and the data of the corresponding block of the data file 2A of the first computer 1A is transferred to the second computer 1B. The function of transmitting through a transmission device,
The above processing is repeated until there is no difference in the data of CRC3A and CRC3B, and CRC3A and CRC3
When the comparison of the data of all the blocks of 3B is completed, a function of notifying the end of transmission to the second computer 1B via the transmission device is provided, and further, the second computer 1B is provided with the function of transmitting the data from the first computer 1A. Based on the transmitted block data,
The second computer 1B is provided with a function of updating the data in the corresponding block of the data file 2B and returning an affirmative response to the first computer 1A via the transmission device.

Therefore, when the data of the data files 2A and 2B of the first computer 1A and the second computer 1B are completely identical, each block of the data file 2B created by the second computer 1B It is possible to confirm that there is no difference between the two data files 2A and 2B by simply transmitting the 16-bit CRC 3B to the first computer 1A.

Further, even if there is a difference between the two data files 2A and 2B, only the data of the different block is transmitted in the unit of dividing the data files 2A and 2B into blocks, and the data files of the both are transmitted. 2A, 2
The matching of B can be ensured.

As a result, even when the computers 1A and 1B are connected to each other by using a transmission device having a relatively low transmission speed, unnecessary data transmission is increased in the case of a data file having a high data equality. Since this does not occur, the matching process of each data file 1A, 1B can be efficiently performed.

Therefore, the initialization processing time when the stopped second computer 1B initializes can be greatly shortened. That is, when the computer (second computer 1B) that has stopped is initialized when the content of the data file 2A is changed by one computer (first computer 1A), the first computer 1A Even if the number and size of the data files 2B for managing the consistency with the data file 2B are relatively large, unnecessary data transmission can be eliminated, and the data transmission time can be shortened by that much. Time (data update time of the data file 2B) is shortened, and as a result, the initialization processing time of the second computer 1B can be significantly shortened.

For the above reason, in order to shorten the data transmission time, the conventional transmission device is
Since it is not necessary to use a transmission device having a relatively high data transmission rate, the computer system can be made inexpensive accordingly.

The present invention is not limited to the above embodiment, but can be implemented in the same manner as described below. (A) In the above embodiment, the case where the present invention is applied to a computer system that has two computers that individually have the same data file and that are connected to each other by a transmission device has been described, but the present invention is not limited to this. Alternatively, the present invention is similarly applied to a computer system including a plurality of computers of three or more, and the same effect as the above case can be obtained.

(B) In the above embodiment, the second computer 1B
The case where the contents of the data file 2B of the above is set to the same value as the contents of the data file 2A of the first computer 1A (when the second computer 1B is initialized) has been described.
Not limited to this, the data file 2A of the first computer 1A
In the case where the contents of the above are set to the same values as the contents of the data file 2B of the second computer 1B (when the first computer 1A is initialized), the respective functions described above are provided in the opposite manner to the case of the above embodiment. By doing so, it can be similarly implemented.

(C) In the above embodiment, the case of creating a 16-bit CRC for each block of the data files 2A and 2B as the CRC 3A and CRC 3B has been described, but the present invention is not limited to this.

(D) In the above embodiment, the second computer 1B
The CRC3B created by 1. is transmitted block by block to the first computer 1A and compared with the data of the CRC3A created by the first computer 1A. However, the present invention is not limited to this. Created C
RC3B, all blocks at once the first computer 1A
CRC3 created by the first computer 1A
Compared with the data of all blocks of A, CR with difference
Only the data of the block C may be transmitted to the second computer 1B. In addition, the present invention can be variously modified and implemented within the scope of the invention.

[0040]

As described above, according to the present invention, data is transferred between the first and second computers that individually have the same data file and are connected to each other by the transmission device via the transmission device. In a computer system that performs matching processing of data files by transmitting each other, each data file is divided into a plurality of blocks, and when a second computer initializes, each block of the data file in the second computer is divided. A means for creating a cyclic check code and transmitting the cyclic check code to the first computer through a transmission device;
Means for creating a cyclic check code for each block of the data file in the computer of No. 2, a data of the cyclic check code created by the first computer, and a second
Means for comparing the cyclic check code data transmitted from the computer in sequence for each block, and when a difference is detected in the cyclic check code data as a result of the comparison, the first computer Based on the means for transmitting the data of the corresponding block of the data file to the second computer via the transmission device, and the data of the corresponding block of the data file of the second computer based on the block data transmitted from the first computer. Since it is equipped with a means for updating, even if a transmission device with a relatively low data transmission rate is used, data file matching processing can be performed efficiently, and initialization can be performed when the stopped computer is initialized. An extremely reliable computer system that can significantly reduce the processing time can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a computer system according to the present invention.

FIG. 2 is a flowchart for explaining the contents of data file matching processing in the computer system of the embodiment.

[Explanation of symbols]

1A ... 1st computer, 1B ... 2nd computer, 2A ... data file, 2B ... data file, 3A ... block CRC of data file 2A, 3B ... data file 2B
Block CRC.

Claims (1)

[Claims] 1. Matching of the data files by mutually transmitting data via the transmission device between first and second computers that have the same data file individually and are connected to each other by the transmission device. In a computer system that performs processing, each of the data files is divided into a plurality of blocks, and when the second computer initializes the second data file,
Means for creating a cyclic check code for each block of a data file in the computer, and transmitting the cyclic check code to the first computer via the transmission device, and data in the first computer A means for creating a cyclic check code for each block of the file, data of the cyclic check code created by the first computer, and data of the cyclic check code transmitted from the second computer, Means for sequentially comparing each block, and as a result of the comparison, when a difference is detected in the data of the cyclic check code, the data of the corresponding block of the data file of the first computer is transferred to the second computer. Means for transmitting via the transmission device, based on the block data transmitted from the first computer And a means for updating the data of the corresponding block of the data file of the second computer, the computer system comprising: