JP4894789B2 - Data back system and data backup control method - Google Patents

Description

  The present invention provides a data backup system and data capable of improving backup transfer performance without using useless system resources in a data backup system that backs up computer data with a backup device connected to another computer. The present invention relates to a backup control method.

  The amount of data handled by companies is increasing as the performance and capacity of storage devices increase. From the viewpoint of disaster countermeasures and compliance with laws and regulations, backup of these data is important.

  Regarding the backup environment, in order to eliminate the increase in backup facilities accompanying the increase in the number of servers owned by companies and the complexity of operation, backup is performed on multiple servers with a single backup device from the method of performing backup individually for each server. Tend to implement. In a backup environment in which a backup of a plurality of servers is performed, a configuration may be employed in which one backup server is installed and data of the plurality of servers is backed up by a backup device connected to the backup server.

  In addition, when the business disk cannot be accessed directly from the backup server, a circulating file on the storage device (shared disk) connected to both servers can be used as a method of transferring data between the server and the backup server. Yes (see, for example, Patent Document 1).

  The circular file processing method described in Patent Document 1 is composed of a data processing device and a circular file. In the circular file, the position following the physical end position of the sequential file is the physical start position of the sequential file. It is configured by defining. The data processing device includes a data output unit, a data input unit, and a circular file management unit. The circular file management unit includes a file data final position management unit and a file data head position management unit. When the data output unit stores data in a circular file or when the data input unit refers to data from the circular file, the writing position or the reading position is shifted to the next point, respectively. By such a method, data can be stored infinitely in one file.

JP-A-2-242350 (pages 3, 4 and 7)

  The backup / restore performance depends on the data transfer performance between the storage device and the business server. In general, the transfer performance increases when the buffer length of the data transfer buffer is increased. When increasing the buffer length, it is necessary to set the buffer length of the data transfer buffer to an appropriate value in order to use a lot of system resources such as a memory used as a buffer and a CPU used for transfer processing.

  However, when backing up using a circular file on the shared disk, data transfer between the business disk and the shared disk in the business server and data transfer between the shared disk and the backup device in the backup server are executed in parallel. Therefore, it is necessary to set both the buffer length on the business server side and the buffer length on the backup server side to appropriate values in consideration of storage device performance, server system resources, processing capacity, and the like.

  Also, when taking the form of backing up the data of multiple business servers with a single backup server, the amount of backup requests from each business server affects the system resources and processing capacity of the backup server. It is difficult to set an appropriate value.

  Therefore, an object of the present invention is to provide a data back system and a data backup control method capable of appropriately controlling the buffer length and improving transfer performance without using useless system resources.

The data backup system according to the present invention is a circulation that temporarily stores data in a computer that can request backup and restore of data, with the restriction that new data is not written in an area in which unread data is stored. A data backup system for backing up to a backup device connected to another computer via a format storage means, the computer temporarily storing data to be output to the circulation format storage means, and a temporary storage means Whether or not data output waiting based on the constraint conditions occurred when outputting data to the cyclic format storage means, and data that can be read to the cyclic format storage means when another computer is reading data from the cyclic format storage means Does not exist, waits for data input Output waiting / input waiting detecting means for detecting whether or not data input waiting that is in the state is generated, and the output waiting / input waiting detecting means when the data in the temporary storage means is output to the circular format storage means. When it is detected that an output wait has occurred, the storage capacity of the temporary storage means is decreased, and when the output wait / input wait detection means detects that a data input wait has occurred, the temporary storage means can be stored. Storable amount determination means for increasing the amount, and when the output wait / input wait detection means inputs data from the cyclic format storage means to the temporary storage means, a data output wait of another computer occurs based on the constraint condition And whether or not a data input wait has occurred when data is being read from the cyclic storage means, and the storable amount determination means When data is input to the temporary storage means, if the output wait / input wait detection means detects that a data input wait has occurred, the storable amount of the temporary storage means is decreased and the output wait / input wait detection is detected. When the means detects that a data output wait has occurred, the storable amount of the temporary storage means is increased .

The data backup control method according to the present invention is such that data in a computer that has temporary storage means and can request data backup and restoration is not written to an area in which unread data is stored. As a data backup method applied to a system for backing up to a backup device connected to another computer via a cyclic storage means for temporarily storing data, the computer stores the data in the temporary storage means in a circular format Whether there is a data output wait based on the constraints when outputting to the means, and when other computers are reading data from the circular form storage means, there is no readable data in the circular form storage means and data input Data input that is waiting for When the detection process detects that a data output wait has occurred when the data in the temporary storage means is output to the cyclic storage means, the detection process detects whether or not the error occurred. When the detection process detects that the amount of data that can be stored is reduced and waiting for data input, the amount of data that can be stored in the temporary storage unit is increased , and restrictions are imposed when data is input from the cyclic storage unit to the temporary storage unit. Performs processing to detect whether waiting for data output from another computer based on the condition has occurred and whether or not waiting for data input has occurred while reading data from the cyclic format storage means, and temporarily stores it from the cyclic format storage means When data is input to the means, and the detection process detects that a data input wait has occurred, the storable amount of the temporary storage means is reduced and the data output wait Wherein the increased detection process when detecting in the storable amount of the temporary storage means that has occurred.

  According to the present invention, it is possible to improve transfer performance without using useless system resources at the time of data backup and restoration.

  First, the outline of the present invention will be described using a business server and a backup server as examples.

  Circulating file management information is provided along with a circulating file on a shared disk connected to both the business server and the backup server. A circular file is a sequential file in which a file area is cyclically used, and a position following a physical end position of the file is a physical start position of the file. The circulation file management information includes output position information and input position information as information for managing the input / output state of the circulation file.

  The business server and the backup server each have backup / restore means, and the backup / restore means of the business server performs the transfer process between the storage device and the circular file, and at the start of the transfer process, the backup server The backup / restore request is notified to the backup / restore means.

  When the backup / restore means of the backup server receives a backup / restore request from the business server, it executes data transfer processing between the circular file and the backup device.

  Both backup / restore means use the circular file input / output means for inputting / outputting the circular file. The circular file input / output means refers to the output position information and the input position information in the circular file management information, and waits together with an input / output completion notification when waiting for output to the circular file or waiting for input is detected. The backup / restore means is notified that the error has occurred.

  The detection method of waiting for output or waiting for input to the circular file is as follows. In other words, when it is detected that the output position has caught up with the input position, it is determined that the output is waiting for the circulation file, and when it is detected that the input position has caught up with the output position, it is transferred to the circulation file. It is determined that it is waiting for output.

  The occurrence of waiting for input / output to the circular file indicates that the transfer processing capacity on the opposite side to the side on which the wait is occurring is lower than the transfer processing capacity on the side on which the wait is occurring. For example, when an output wait occurs in the output process for the circulation file of the business server, it indicates that the processing capacity of the input process for the circulation file of the backup server is lower than the output process for the circulation file of the business server.

  Since the backup / restore performance is suppressed by the transfer performance on the lower side, it is inefficient to wait for input / output to the circular file. Therefore, when detecting the occurrence of waiting, the backup / restore means changes the buffer length by the buffer length determining means and performs the next transfer process. The method for determining the buffer length in the buffer length determining means is as follows.

  In the output process for the circular file, if it is detected that there is no area that can be output, the buffer length is reduced. In addition, in the output processing for the circular file, when the occurrence of data waiting on the input processing side is detected, the buffer length is increased. In the input process for the circular file, the buffer length is reduced when waiting for data. In addition, in the input processing for the circular file, when the occurrence of waiting for the area on the output processing side is detected, the buffer length is increased. When waiting occurs in the input / output of the circular file, the buffer length on the side where the waiting is generated is reduced, so that the amount of memory used as a buffer can be limited to the necessary amount, and waste of resources can be saved. In addition, by increasing the buffer length on the opposite side to the side where waiting is occurring in the input / output of the circular file, the transfer performance on the bottleneck side can be increased, and the overall transfer performance can be improved.

  In other words, the present invention utilizes the fact that input waiting and output waiting occur due to input and output to the circulating file, which is a feature of the circulating file. When input waiting and output waiting occur, the input side and output of the circulating file The buffer length on the side is changed. Specifically, the buffer length of the input computer (business server or backup server) and the buffer length of the output computer (backup server or business server) are changed. That is, the buffer length determining means of each computer refers not only to the waiting status of input and output waiting for the circulating file of its own computer, but also to the waiting status of waiting for input and output waiting for the other computer circulating file using the circulating file. To determine the buffer length of the local computer.

  By continuing the above processing, it is possible to reduce the occurrence of waiting for input processing and output processing, and to improve the transfer performance of backup / restore processing.

  Note that the buffer length determining means increases the buffer length when the target transfer performance has not been reached in order to prevent the transfer performance from becoming unstable with low transfer performance. The target transfer performance is set by calculating in advance from the theoretical value of the processing capacity of the storage device or business server.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of a data back system to which a data backup / restore method according to the present invention is applied.

  The data back system shown in FIG. 1 includes a business server group 100, a backup server 200 that operates under program control, a storage device group 300, and a storage device connected to both the business server group 100 and the backup server 200. 400 and a backup apparatus 500 connected only to the backup server 200 are included.

  The business server group 100 includes a plurality of business servers 100A, 100B,..., 100N that operate by program control. The storage device group 300 includes a storage device 300A connected only to the business server 100A, a storage device 300B connected only to the business server 100B, and a storage device 300N connected only to the business server 100N. In FIG. 1, three business servers 100A, 100B, and 100N and three storage devices 300A, 300B, and 300N are shown, but the business server group 100 and the storage device group 300 each include One or two devices may be included, or four or more devices may be included.

  Hereinafter, the configuration of the business server 100A will be described. The configuration of the business servers 100B to 100N is the same as the configuration of the business server 100A.

  The business server 100A outputs backup / restore means 110, input / output means 120 that outputs data to the storage apparatus 300A and inputs data from the storage apparatus 300A, and outputs data to the storage apparatus 400 and inputs data from the storage apparatus 400A. A circulating file input / output unit 121 and a buffer (temporary storage unit) 130 are provided.

  The backup / restore means 110 has a data copy function for the storage apparatus 300A and the storage apparatus 400. That is, it has a function of copying data in the storage apparatus 300A to the storage apparatus 400 at the time of backup and copying data in the storage apparatus 400 to the storage apparatus 300A at the time of restoration. Further, the backup / restore means 110 has a function of notifying the backup server 200 of a backup / restore request.

  Further, the backup / restore means 110 is provided with a buffer length determining means 111. The buffer length determination unit 111 has a function of determining the buffer length based on the input / output waiting state of the circulation file 420. Further, it has a function of periodically measuring the transfer performance between the circulation file 420 and the buffer 130 and storing it in a memory (for example, included in the backup / restore means 110).

  The backup server 200 includes a backup / restore unit 210, an input / output unit 220 that outputs data to the backup device 500 and inputs data from the backup device 500, and outputs data to the storage device 400 and inputs data from the storage device 400. A circular file input / output unit 221 and a buffer 230 are provided.

  The backup / restore means 210 has a data copy function for the storage apparatus 400 and the backup apparatus 500 based on the backup / restore request notified from the business server 100A.

  Further, the backup / restore means 210 is provided with a buffer length determination means 211. The buffer length determination unit 211 has a function of determining the buffer length based on the input / output waiting state of the circulation file 420. Further, it has a function of periodically measuring the transfer performance between the circulation file 420 and the buffer 230 and storing it in the memory.

  The storage apparatus 400 includes circular file management information 410 and a circular file 420. The circular file 420 is a sequential file in which a file area is cyclically used, and a position following the physical end position of the file is a physical start position of the file.

  FIG. 2 is an explanatory diagram showing a configuration example of the circulating file management information 410. The circulation file management information 410 includes output position information 411 and input position information 412 as information for managing the input / output state of the circulation file. The circulating file management information 410 is physically information stored in a predetermined memory area in the storage apparatus 400.

  FIG. 3 is an explanatory diagram showing an example of transition between the output position and the input position in the circulation file 420.

  In the following description, “output data” means output data to the circulation file 420, and “read data” means read data from the circulation file 420. Further, in FIG. 3, “output completed, non-input area” has data output to the area (memory area) indicated by numbers 1 to N, but the data has not been read yet (backup In this case, it indicates that the data has not been input to the backup server 200.) Indicates an area. “Output completed, input completed area” indicates that data is output to an area indicated by numbers 1 to N and data is read from the area. The “output position” indicates that data has been output up to that position. “Input position” indicates that data has been read up to that position.

  FIG. 3A shows a state where data is output to the circulation file 420. Unread output data exists up to the position of number 4. In the circular file management information 410 in the state shown in FIG. 3A, the output position information 411: “4” and the input position information 412: “0”.

  FIG. 3B shows a state in which data output and data reading are performed from the state shown in FIG. It indicates that there is unread output data up to the position of number 16 and data has been input up to the position of number 8. In the circular file management information 410 in the state shown in FIG. 3B, the output position information 411: “16” and the input position information 412: “8”.

  FIG. 3C shows a state in which data output has advanced from the state shown in FIG. It indicates that there is unread output data up to the position of number N. In the circular file management information 410 in the state shown in FIG. 3C, the output position information 411: “N” and the input position information 412: “8”.

  FIG. 3D shows a state in which data output has advanced from the state shown in FIG. Since the file has been output up to the physical end position (number N in the example shown in FIG. 3), it returns to the physical start position of the file (number 1 in the example shown in FIG. 3). The state where data is output at the position of is shown. In the circular file management information 410 in the state shown in FIG. 3D, the output position information 411: “1” and the input position information 412: “8”.

  FIG. 4 is an explanatory diagram showing an example of an input / output wait occurrence state of the circulation file 420. FIG. 4E shows a state in which data output has advanced from the state shown in FIG. This indicates that unread output data exists up to the position of number 7. If data is further output in this state, data that has not been read is destroyed, and output is awaited. In other words, the circulation file 420 temporarily stores data on the condition that new data is not written in an area where unread data is stored. In the circular file management information 410 in the state shown in FIG. 4E, the output position information 411: “7” and the input position information 412: “8”.

  For the sake of simplicity, it is assumed that the output is waited when the value indicated by the output position information 411 is 1 smaller than the value indicated by the input position information 412. When the data is defined to indicate that it has been read, the output waits when the value indicated by the output position information 411 is equal to the value indicated by the input position information 412. That is, when the value indicated by the output position information 411 = the value indicated by the input position information 412, the output position information 411 has caught up with the input position information 412.

  FIG. 4F illustrates a state in which data reading has progressed from the state illustrated in FIG. It indicates that the position of number 6 has been read (input completed). If further data reading is performed in this state, the output waits for input because there is already output data. In the circular file management information 410 in the state shown in FIG. 4F, the output position information 411: “7” and the input position information 412: “6”.

  Next, the operation of the data back system will be described. First, a data backup operation, that is, an operation when data is transferred from the business server 100A to the backup server 200 via the storage apparatus 400 will be described with reference to the flowchart of FIG.

  The backup / restore means 110 of the business server 100A notifies the backup server 200 of a backup request at the start of backup (step A1). The backup request includes the file name of the circulation file 420.

  Thereafter, the backup / restore unit 110 reads the backup target data stored in the storage apparatus 300A to the buffer 130 via the input / output unit 120 (step A2). The circulation file input / output unit 121 is requested to output from the buffer 130 to the circulation file 420.

  The circular file input / output unit 121 refers to the output position information 411 and the input position information 412 in the circular file management information 410 and determines whether data can be output (step A3). If the output is possible, that is, if the output position information 411 does not catch up with the input position information 412, data is output (step A4). If the output is not possible, that is, if the output position information 411 has caught up with the input position information 412, the process waits for the input position information 412 to proceed (step A5). The circulating file input / output unit 121 increments the value of the output position information 411 by 1 when data is output to one entire area in the circulating file 420.

  As a method of determining whether the input position information 412 has been advanced and can be output, for example, a method of periodically referring to the circulating file management information 410 or a circulating file input / output unit 221 in the backup server 200 A method of notifying the circular file input / output means 121 at the timing when the value of the input position information 412 of the information 410 is advanced is conceivable.

  When the output is completed, the circulating file input / output unit 121 notifies the backup / restore unit 110 of the output waiting occurrence information together with the processing result.

  When the circular file input / output means 121 detects that an input wait has occurred when referring to the output position information 411 and the input position information 412 in the circular file management information 410, that is, When the input position information 412 catches up with the output position information 411, the backup / restore means 110 is notified of the input wait along with the processing result.

  When the backup / restore unit 110 receives the notification of the output waiting occurrence information from the circular file input / output unit 121, the backup / restore unit 110 uses the buffer length determination unit 111 to determine the buffer length of the buffer 130 to be used next time.

  When waiting for output, the buffer length determining unit 111 reduces the buffer length of the buffer 130 to be used next time (steps A6 and A7). That is, the buffer size is reduced. If no output wait has occurred, it is checked whether an input wait has occurred (step A8). If waiting for input has occurred, the buffer length of the buffer 130 to be used next time is expanded (step A9). That is, the buffer size is increased.

  If neither output waiting nor input waiting has occurred, it is confirmed whether the target transfer performance has been reached (step A12). If the target transfer performance has not been reached, the buffer length of the buffer 130 to be used next time is increased. (Step A13). That is, the buffer size is increased.

  As a method of reducing the buffer length, the buffer length is set to a predetermined ratio (for example, 90%) with respect to the buffer length before the reduction, or a predetermined amount (for example, secured as the buffer 130) with respect to the buffer length before the reduction. Or 10% of the maximum possible number of bytes). Further, as a method of expanding the buffer length, the buffer length is set to a predetermined ratio (for example, 110%) with respect to the buffer length before the expansion, or secured as a predetermined amount (for example, the buffer 130) relative to the buffer length before the expansion. It may be possible to increase 10% of the maximum possible number of bytes). However, the buffer length after expansion is limited to the maximum number of bytes that can be secured as the buffer 130.

  Further, when the buffer length is reduced, the reduction amount may be determined according to the number of output waiting occurrences or the output waiting time. That is, when the number of output waiting occurrences is greater than a predetermined value or when the output waiting time is longer than a predetermined time, the reduction amount may be increased. Further, when the buffer length is expanded, the expansion amount may be determined according to the number of occurrences of input waiting and the input waiting time. That is, when the number of occurrences of input waiting is greater than a predetermined value or when the input waiting time is longer than a predetermined time, the enlargement amount may be increased.

  Thereafter, the backup / restore means 110 confirms whether or not all the backup target data stored in the storage apparatus 300A has been output to the circular file 420 (step A10). Wait for the backup result from the server 200 (step A11). If there is data that has not been output to the circulation file 420, a read process to the buffer 130 is performed (step A2).

  In the backup server 200, when the backup / restore means 210 receives a notification of the backup request from the business server 100A (step B1), the storage apparatus 400 uses the circular file input / output means 221 based on the notified backup request. The data is read from the buffer 230 to the buffer 230 and output from the buffer 230 to the backup device 500 using the input / output means 220.

  The circulating file input / output means 221 refers to the output position information 411 and the input position information 412 in the circulating file management information 410 and determines whether data can be input (step B2). If input is possible, that is, if the input position information 412 does not catch up with the output position information 411, data is input (step B3). When the input is not possible, that is, when the input position information 412 catches up with the output position information 411, the output position information 411 is waited for to proceed (step B4), and data is input. The circulating file input / output unit 221 increments the value of the input position information 412 by 1 when all data in one area in the circulating file 420 is read.

  As a method for determining whether or not the output position information 411 has been advanced and can be input, for example, a method of periodically referring to the circulating file management information 410, or the circulating file input / output means 121 in the business server 100A is used for the circulating file management. A method of notifying the circular file input / output means 221 at the timing when the value of the output position information 411 of the information 410 is advanced is conceivable.

  When the input is completed, the circular file input / output unit 221 notifies the backup / restore unit 210 of the input wait occurrence information together with the processing result.

  When the circulating file input / output unit 221 refers to the output position information 411 and the input position information 412 in the circulating file management information 410 and detects that output waiting has occurred, that is, When the output position information 411 has caught up with the input position information 412, the backup / restore means 210 is notified of the output waiting together with the processing result.

  When the backup / restore unit 210 receives notification of the waiting occurrence information from the circular file input / output unit 221, the backup / restore unit 210 uses the buffer length determination unit 211 to determine the buffer length of the buffer 230 to be used next time.

  The buffer length determination unit 211 reduces the buffer length of the buffer 230 to be used next time when an input wait occurs (steps B5 and B6). That is, the buffer size is reduced. If no input wait has occurred, it is checked whether an output wait has occurred in the business server 100A (step B7). If output waiting has occurred, the buffer length of the buffer 230 to be used next time is expanded (step B8). That is, the buffer size is increased.

  If neither input wait nor output wait has occurred, it is confirmed whether the target transfer performance has been reached (step B12). If the target transfer performance has not been reached, the buffer length of the buffer 230 to be used next time is increased. (Step B13). That is, the buffer size is increased.

  Thereafter, the backup / restore means 210 uses the input / output means 220 to output the contents of the buffer 230 to the backup device 500 (step B9).

  Then, the backup / restore means 210 confirms whether or not all the data of the circular file 420 has been output to the backup device 500 (step B10), and when the output of all the data is completed, the backup result is sent to the business server 100A. Notification is made (step B11). If there is data that has not been output to the backup device 500, a read process to the buffer 230 is performed (step B2).

  Next, an operation of restoring data, that is, an operation when transferring data from the backup server 200 to the business server 100A via the storage apparatus 400 will be described with reference to a flowchart of FIG.

  The backup / restore unit 110 of the business server 100A notifies the backup server 200 of a restore request at the start of the restore (step C1). The restore request includes the file name of the circular file 420.

  Thereafter, the backup / restore means 110 reads the restored data from the storage apparatus 400 to the buffer 130 using the circular file input / output means 121, and outputs the data from the buffer 130 to the storage apparatus 300A using the input / output means 120. .

  The circulating file input / output unit 121 refers to the output position information 411 and the input position information 412 in the circulating file management information 410 and determines whether or not data can be input (step C2). If input is possible, that is, if the input position information 412 does not catch up with the output position information 411, data is input (step C3). If input is not possible, that is, if the input position information 412 catches up with the output position information 411, the output position information 411 is waited for to proceed (step C4), and data is input. The circular file input / output unit 121 increments the value of the input position information 412 by 1 when all data of one area in the circular file 420 is read.

  As a method of determining whether the output position information 411 has been advanced and can be input, for example, a method of periodically referring to the circulating file management information 410 or a circulating file input / output means 221 in the backup server 200 A method of notifying the circular file input / output means 121 at the timing when the value of the output position information 411 of the information 410 is advanced is conceivable.

  When the input is completed, the circular file input / output unit 121 notifies the backup / restore unit 110 of the input / output wait occurrence information together with the processing result.

  Note that when referring to the output position information 411 and the input position information 412 of the circular file management information 410, it is detected that the backup server 200 is waiting for output, that is, the output position information 411. Is caught up with the input position information 412, the backup / restore means 110 is notified of the output waiting together with the processing result.

  When the backup / restore unit 110 receives the notification of the waiting occurrence information from the circular file input / output unit 121, the backup / restore unit 110 uses the buffer length determination unit 111 to determine the buffer length of the buffer 130 to be used next time.

  The buffer length determination unit 111 reduces the buffer length of the buffer 130 to be used next time when an input wait occurs (steps C5 and C6). That is, the buffer size is reduced. If no input wait has occurred, it is checked whether an output wait has occurred (step C7). If output waiting has occurred, the buffer length of the buffer 130 to be used next time is expanded (step C8). That is, the buffer size is increased.

  If neither input wait nor output wait has occurred, it is confirmed whether or not the target transfer performance has been reached (step C12). If the target transfer performance has not been reached, the buffer length of the buffer 130 to be used next time is expanded (step C13). That is, the buffer size is increased.

  Thereafter, the backup / restore means 110 uses the input / output means 120 to output the contents of the buffer 130 to the storage apparatus 300A (step C9).

  The backup / restore means 110 confirms whether all the data of the circular file 420 has been output to the storage apparatus 300A (step C10), and when the output of all the data is completed, waits for the restore result from the backup server 200. (Step C11). If there is data that has not been output to the storage apparatus 300A, a read process to the buffer 130 is performed (step C2).

  In the backup server 200, when the backup / restore unit 210 receives a restore request notification from the business server 100A (step D1), the backup / restore unit 210 uses the input / output unit 220 based on the notified restore request from the backup device 500. Data is read into the buffer 230 (step D2), and the circulation file input / output means 221 is requested to output to the circulation file 420.

  The circulating file input / output unit 221 refers to the output position information 411 and the input position information 412 in the circulating file management information 410 and determines whether data can be output (step D3). If output is possible, that is, if the output position information 411 does not catch up with the input position information 412, data is output (step D4). If output is not possible, that is, if the output position information 411 has caught up with the input position information 412, the process waits for the input position information 412 to proceed (step D5). The circulating file input / output unit 221 increments the value of the output position information 411 by 1 when data is output to one entire area in the circulating file 420.

  As a method for determining whether or not the input position information 412 has been advanced and can be output, for example, a method of referring to the circular file management information 410 periodically, or the circular file input / output means 121 in the business server 100A is a circular file management. A method of notifying the circular file input / output means 221 at the timing when the value of the input position information 412 of the information 410 is advanced is conceivable.

  When the output is completed, the circular file input / output unit 221 notifies the backup / restore unit 210 of the output wait occurrence information together with the processing result.

  When the output position information 411 of the circular file management information 410 and the input position information 412 are referred to, when it is detected that input waiting has occurred, that is, the input position information 412 is output position information. If it has caught up to 411, it notifies the backup / restore means 210 that the input wait has occurred together with the processing result.

  When the backup / restore means 210 receives the notification of the output waiting occurrence information from the circular file input / output means 221, the backup / restore means 210 uses the buffer length determination means 211 to determine the buffer length of the buffer 230 to be used next time.

  When waiting for output, the buffer length determining unit 211 reduces the buffer length of the buffer 230 to be used next time (steps D6 and D7). That is, the buffer size is reduced. If no output wait has occurred, it is checked whether an input wait has occurred (step D8). If waiting for input has occurred, the buffer length of the buffer 230 to be used next time is expanded (step D9). That is, the buffer size is increased.

  If neither output waiting nor input waiting has occurred, it is confirmed whether or not the target transfer performance has been reached (step D12). If the target transfer performance has not been reached, the buffer length of the buffer 230 to be used next time is expanded (step D13). That is, the buffer size is increased.

  As described above, in this embodiment, transfer performance can be improved without using useless system resources. This is because the buffer length on both the output processing side and the input processing side to the circular file is changed at the time of backup / restoration. When waiting for circular file I / O, by reducing the buffer length of the waiting side, the amount of memory used as a buffer can be reduced to the required amount, and resources can be saved. . In addition, by increasing the buffer length on the opposite side to the side that is waiting for circular file I / O, the number of data I / O start control times between the buffer and storage device is reduced, and the transfer performance on the bottleneck side And the overall transfer performance can be improved.

  In addition, in a form in which data of a plurality of business servers is backed up by a single backup server, the processing capacity of the backup server changes according to the backup request amount from each business server. Transfer performance can be improved according to the backup load without using resources.

  FIG. 7 is a block diagram showing the main configuration of the data back system according to the present invention. As shown in FIG. 7, the data back system includes a computer 1 capable of requesting data backup and restoration, another computer 2 connected to the backup device 4, and the computer 1 and the computer 2 respectively. The computer 1 includes a circulation format storage means 3 for storing data in a cyclic file format that can be output, and the computer 1 temporarily stores data to be output to the circulation format storage means 3 and data in the temporary storage means 1A. Whether or not the data output wait based on the constraint condition (do not write new data in the area in which unread data is stored) occurs when the data is output to the circulation format storage means 3, and the other computer 2 When data is being read from the storage means 3, data that can be read out to the circular format storage means 3 Output waiting / input waiting detecting means 1C for detecting whether or not there is a data input waiting state that is waiting for data input, and data in the temporary storage means 1A is output to the cyclic storage means 3 When the output wait / input wait detection means 1C detects that data output wait has occurred, the storable amount of the temporary storage means 1A is decreased, and the output wait / input wait detection means 1C has waited for data input. When this is detected, there is provided a storable amount determining means 1B for increasing the storable amount of the temporary storage means 1A.

  Further, the output waiting / input waiting detecting means 1C determines whether or not the data output waiting of the other computer 2 has occurred based on the constraint conditions when data is input from the circulating form storage means 3 to the temporary storage means 1A. It is detected whether or not a data input wait has occurred while reading data from the means 3, and the storable amount determination means 1B waits for an output when data is input from the cyclic storage means 3 to the temporary storage means 1A. / When the input wait detection means 1C detects that data input wait has occurred, the storable amount of the temporary storage means 1A is decreased, and the output wait / input wait detection means 1C detects that data output wait has occurred. In this case, the storable amount of the temporary storage unit 1A is increased.

  The other computer 2 is equipped with functions corresponding to the functions of the temporary storage means 1A, the output waiting / input waiting detection means 1C, and the function of the storable amount determination means 1B.

It is a block diagram which shows the structural example of the data back system with which the data backup / restore method by this invention is applied. It is explanatory drawing which shows the structural example of circulating file management information. It is explanatory drawing which shows the example of the transition of the output completed position and input completed position in a circulation file. It is explanatory drawing which shows the example of the input / output waiting generation state of a circulation file. First, it is a flowchart showing a data backup operation. It is a flowchart which shows the operation | movement of data restoration. It is a block diagram which shows the main structures of the data back system by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Computer 1A Temporary storage means 1B Memory | storage amount determination means 1C Output waiting / input waiting detection means 2 Other computer 3 Circulation type storage means 100 Business server group 100A, 100B, 100N Business server 110 Backup / restoration means 111 Buffer length determination means 120 I / O Unit 121 Circular File I / O Unit 130 Buffer 200 Backup Server 210 Backup / Restore Unit 211 Buffer Length Determining Unit 220 I / O Unit 221 Circular File I / O Unit 230 Buffer 300 Storage Device Group 300A, 300B, 300N Storage Device 400 Storage Device 410 Circular file management information 411 Output location information 412 Input location information 420 Circular file 500 Backup device

Claims (7)

The data in the computer that can request backup and restore of data is transferred via a circular storage means that temporarily stores data with the restriction that new data is not written in the area where unread data is stored. A data backup system for backing up to a backup device connected to a computer of
A computer capable of requesting backup and restore of the data is:
Temporary storage means for temporarily storing data to be output to the circulation format storage means;
Whether or not data output waiting based on the constraint condition occurred when outputting the data in the temporary storage means to the circulation format storage means, and when the other computer is reading data from the circulation format storage means An output wait / input wait detection means for detecting whether or not a data input wait has occurred in a state where there is no readable data in the circulation format storage means and waiting for data input;
When the data stored in the temporary storage unit is output to the circulation format storage unit, the storable amount of the temporary storage unit is reduced when the output wait / input wait detection unit detects that data output wait has occurred. A storable amount determining means for increasing the storable amount of the temporary storage means when the output wait / input wait detection means detects that a data input wait has occurred ,
The output wait / input wait detection means is configured to determine whether a data output wait of another computer based on the constraint condition occurs when data is input from the circulation form storage means to the temporary storage means, and the circulation form storage means. Detecting whether data input wait occurred while reading data from
The storable amount determining means, when data is input from the circulation format storage means to the temporary storage means, and the output wait / input wait detection means detects that the data input wait has occurred, A data backup characterized by decreasing the storable amount of the storage means and increasing the storable amount of the temporary storage means when the output wait / input wait detection means detects that a data output wait has occurred system. Backup and restore can be requested computer data, after storing in the temporary storage data inputted from the storage device, data backup according to claim 1, further comprising a backup means for controlling to output the circulation format storing means system. 3. The data backup according to claim 2 , wherein the computer capable of requesting backup and restore of data comprises a restore means for controlling the data inputted from the circular storage means to be output to the storage device after being stored in the temporary storage means. system. Other computers connected to the backup device
Temporary storage means for temporarily storing data to be output to the circulation format storage means;
An output for detecting whether or not a data output wait based on a restriction condition has occurred when outputting the data of the temporary storage means to the circulation format storage means and whether or not a data input wait has occurred in the computer that requested the data restoration. Wait / input wait detection means;
When the data stored in the temporary storage unit is output to the circulation format storage unit, the storable amount of the temporary storage unit is reduced when the output wait / input wait detection unit detects that data output wait has occurred. The storable amount determining means for increasing the storable amount of the temporary storage means when the output wait / input wait detection means detects that a data input wait has occurred. 4. The data backup system according to any one of 3 . The output waiting / input waiting detecting means in another computer connected to the backup device is a computer that can request backup and restoration of data based on the constraint condition when inputting data from the cyclic storage means to the temporary storage means. Detecting whether a data output wait has occurred and whether a data input wait has occurred in a state in which no readable data exists when reading data from the circular storage means;
The storable amount determining means in the other computer connected to the backup device, when the data is input from the cyclic storage means to the temporary storage means, the output wait / input wait detection means is waiting for data input. Is detected, the storable amount of the temporary storage unit is decreased, and the storable amount of the temporary storage unit is decreased when the output wait / input wait detection unit detects that data output wait has occurred. The data backup system according to claim 4 , wherein the data backup system is increased. The data backup system according to any one of claims 1 to 5 , comprising a plurality of computers capable of requesting data backup and restoration. Circular format storage that temporarily stores data on a computer that has temporary storage means and can request backup and restore of data, with the restriction that new data is not written in the area where unread data is stored A data backup method applied to a system for backing up to a backup device connected to another computer via means,
A computer capable of requesting backup and restore of the data,
Whether or not data output waiting based on the constraint condition occurred when outputting the data in the temporary storage means to the circulation format storage means, and when the other computer is reading data from the circulation format storage means A detection process is performed to detect whether or not there is a data input wait in a state where there is no readable data in the circulation format storage means and data input is waiting,
When the data stored in the temporary storage means is output to the circulation format storage means, and the detection process detects that a data output wait has occurred, the storable amount of the temporary storage means is decreased, and data input wait When the detection process detects that the error occurred, increase the storable amount of the temporary storage means ,
Waiting for data input when data is being read from the cyclic storage means whether or not another computer has been waiting for data output based on the constraints when inputting data from the cyclic storage means to the temporary storage means Process to detect whether or not
When data is input from the cyclic format storage unit to the temporary storage unit and the detection process detects that a data input wait has occurred, the storable amount of the temporary storage unit is decreased and data output is waited for. A data backup control method characterized by increasing the storable amount of the temporary storage means when it is detected by the detection processing that the occurrence of the error has occurred .

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