JP5776499B2 - Synchronization method, synchronization program, and information processing apparatus - Google Patents

Description

  The present invention relates to a synchronization method, a synchronization program, and an information processing apparatus.

  With the recent increase in network speed and capacity, a large number of files can be sent and received not only between computers connected via a LAN (Local Area Network) but also between computers connected via a network. It was. As one aspect of such file transmission / reception, a synchronization process for matching contents held between a plurality of servers is performed.

  Distribution of distribution load is important in applications that distribute data to a large number of personal computers (PCs), such as distribution of OS (Operating System) security patches and distribution of updated virus definition files. . For example, by providing a multistage resource distribution server, synchronizing distribution data from the master server that is the distribution source to the lower subserver, and allowing each PC to access the subserver instead of the master server, the distribution load can be distributed. It has been broken.

  In such synchronization of distribution data between servers, since the total number of target folders and files is very large, synchronization processing is performed by creating a file list. For example, a client server system is disclosed in which a differential file list is created by comparing file lists created on both the server side and the client side that perform synchronous processing, and the synchronous processing is performed based on the differential file list.

JP 2010-49647 A

  However, the above-described conventional technique has a problem that the file list creation time increases as the number of folders and files to be managed increases, regardless of the number of folders and files that are differences.

  That is, the amount of processing executed as the synchronization processing, for example, the amount of file addition, update, or deletion, differs greatly when the change requiring synchronization processing covers the entire data to be managed and only a part of the data to be managed. . Nonetheless, in the client server system described above, the file list is created every time synchronization processing is performed, and therefore, when only a part of the changes need to be synchronized processing is required, excessive processing time is required to create the file list. .

  The disclosed technology has been made in view of the above, and an object of the present invention is to provide a synchronization method, a synchronization program, and an information processing apparatus that can shorten the creation time of a file list.

  The synchronization method disclosed in this application is a synchronization method between different file systems, in which a computer executes a process of creating a file list in advance for files to be synchronized. Further, the computer executes processing for acquiring an event related to the update of the file. Further, the computer executes a process of calculating the number of update files from which the event has been acquired. Furthermore, when the ratio of the number of update files to the total number of files to be synchronized exceeds a first threshold, the computer executes a process of partially updating the file list. Further, when the ratio of the number of update files to the total number of files to be synchronized exceeds a second threshold value that is larger than the first threshold value, the file list is not partially updated but the file list is updated. Execute processing to re-create the list.

  According to one aspect of the synchronization method disclosed in the present application, there is an effect that the creation time of the file list can be shortened.

FIG. 1 is a diagram illustrating a system configuration of the data distribution system according to the first embodiment. FIG. 2 is a block diagram illustrating a functional configuration of the main server according to the first embodiment. FIG. 3 is a diagram illustrating an example of a subordinate number list. FIG. 4 is a diagram illustrating an example of a file list. FIG. 5 is a diagram for explaining a file update event stacking method. FIG. 6 is a schematic diagram of a graph showing the relationship between the time required to create a file list and the number of updated files. FIG. 7 is a schematic diagram of a graph showing the relationship between the time required to create a file list and the number of updated files. FIG. 8 is a flowchart illustrating a procedure of stack processing according to the first embodiment. FIG. 9 is a flowchart illustrating the procedure of the first monitoring process according to the first embodiment. FIG. 10 is a flowchart illustrating the procedure of the second monitoring process according to the first embodiment. FIG. 11 is a schematic diagram illustrating an example of a computer that executes a synchronization program according to the first and second embodiments.

  Hereinafter, embodiments of a synchronization method, a synchronization program, and an information processing apparatus disclosed in the present application will be described in detail with reference to the drawings. Note that this embodiment does not limit the disclosed technology. Each embodiment can be appropriately combined within a range in which processing contents are not contradictory.

[System configuration]
First, the system configuration of the data distribution system according to the present embodiment will be described. FIG. 1 is a diagram illustrating a system configuration of the data distribution system according to the first embodiment. The data distribution system 1 illustrated in FIG. 1 performs a synchronization process for matching data held between file systems provided by an operating system operating on the main server 10 and the plurality of sub servers 30A to 30C, and is not illustrated. Distribution of data to the terminal device is executed by being distributed to the plurality of sub-servers 30A to 30C.

  As shown in FIG. 1, the data distribution system 1 accommodates a main server 10 and a plurality of sub-servers 30A to 30C. In the example of FIG. 1, the case where three sub servers 30 </ b> A to 30 </ b> C are accommodated is illustrated.

  The main server 10 and the sub servers 30 </ b> A to 30 </ b> C are connected via the network 3 so that they can communicate with each other. As the network 3, any communication network such as a LAN (Local Area Network), a VPN (Virtual Private Network), and the Internet can be adopted.

  Among these, the main server 10 is a server device that distributes data to be distributed to a terminal device (not shown) to the sub server 30. As an aspect, the main server 10 creates a file list stored in a synchronization target folder set so as to synchronize data with the sub server 30 and transmits the file list to the sub servers 30A to 30C. The “synchronization target folder” mentioned here includes the entire directory having the folder set as the synchronization target as the root folder, that is, the root folder and folders belonging to the lower folder. Thereafter, the main server 10 transmits the difference file detected between the two file lists created by the main server 10 and the sub servers 30A to 30C to the sub servers 30A to 30C.

  The sub servers 30A to 30C are server devices that distribute data held by the own device to terminal devices (not shown). As one aspect, the sub servers 30 </ b> A to 30 </ b> C create a file list stored in a synchronization target folder set to synchronize data with the main server 10. Then, the sub servers 30 </ b> A to 30 </ b> C detect a difference between the previously created file list and the file list transferred from the main server 10. Thereafter, the sub servers 30 </ b> A to 30 </ b> C obtain from the main server 10 a file in which a difference is detected between the two file lists. Thereby, the sub servers 30A to 30C make the content of the data held by the main server 10 coincide with the content of the data held by the own device. Hereinafter, the sub server 30A to the sub server 30C may be collectively referred to as “sub server 30” when collectively referred to.

[Main server configuration]
Subsequently, a functional configuration of the main server 10 according to the present embodiment will be described. FIG. 2 is a block diagram illustrating a functional configuration of the main server 10 according to the first embodiment. As shown in FIG. 2, the main server 10 includes a communication I / F (interface) unit 11, a storage unit 12, and a control unit 13. The main server 10 is assumed to have various functions of a known computer other than the functions shown in FIG. 2, such as various input devices and display devices.

  Among these, the communication I / F unit 11 is an interface that performs communication control with another device, for example, the sub server 30. As an example, the communication I / F unit 11 transmits a file list created by the main server 10 to the sub server 30. As another example, the communication I / F unit 11 receives from the sub server 30 an acquisition request for a file in which a difference is detected between the file lists created by the main server 10 and the sub server 30. As an aspect of the communication I / F unit 11, a network interface card (NIC) such as a LAN card or a modem can be employed.

  The storage unit 12 stores various programs such as an OS (Operating System) executed by the control unit 13 and a synchronization program that executes data synchronization processing with the sub server 30. Further, the storage unit 12 stores an update folder list 12a, a subordinate number list 12b, and a file list 12c as an example of data necessary for executing the program executed by the control unit 13.

  Among them, the update folder list 12a is list data of folders that have been updated. As an example, a folder having an updated file under the synchronization target folder is added to the update folder list 12a by a stack unit 13b described later. As another example, the update folder list 12a is cleared by a later-described partial update unit 13c or a later-described creation unit 13e when a later-described file list 12c is partially updated or recreated. As an aspect of the updated folder list 12a, an absolute path of a folder that has been updated, a so-called full path can be adopted.

  The subordinate number list 12b is list data of the number of files subordinate to each folder. As an example, the subordinate number list 12b is updated by a later-described partial updating unit 13d or a later-described creating unit 13e when a later-described file list 12c is partially updated or re-created.

  As one aspect of the subordinate number list 12b, data in which the number of folders and files under the folder are associated can be employed. FIG. 3 is a diagram illustrating an example of the subordinate number list 12b. In FIG. 3, the capital letter of the alphabet in the figure represents the folder name. In the example of FIG. 3, there are three files under the folder A, two files under the folder K, three files under the folder B, and further under the folder C. Indicates that there are 7 files. In this example, the number of files under the folder is stored in association with each other. However, for example, a hierarchical relationship between folders, for example, an upper folder or a lower folder may be further stored.

  The file list 12 c is file list data held by the main server 10. As an example, the file list 12c is newly created by the creation unit 13e described later when the file list is in an initial state in which no file list is registered in the storage unit 12. As another example, in the file list 12c, when the ratio of the number of updated files to the total number of files to be synchronized exceeds a predetermined threshold β, a list regarding folders in the updated folder list 12a is described later. Partial update is performed by the partial update unit 13d. As a further example, the file list 12c is re-created by the creation unit 13e described later when the ratio of the number of updated files to the total number of files to be synchronized exceeds a predetermined threshold value α.

  As an aspect of the file list 12c, data in which files, sizes, attributes, and hash values are associated can be employed. The “attribute” here refers to the property of the file. For example, read-only attribute (Read-only file), archive attribute (Archive file), system file attribute (System file), hidden file attribute (Hidden file), etc. Can be mentioned. The “hash value” refers to a pseudo-random number generated using a hash function, and is used, for example, to check the identity of a file.

  FIG. 4 is a diagram illustrating an example of the file list 12c. In FIG. 4, uppercase letters in the figure represent folder names, lowercase letters in the figures represent file names, and “.xxx” in the figure represents an extension. In the example of FIG. 4, the file a1, the file a2, and the file a3 are all files stored in the folder A under the root folder of the D drive and indicate that the read-only attribute is given. In the example of FIG. 4, the file k1 and the file k2 are both files stored in the folder K under the folder A. The file k1 has an archive attribute, and the file k2 has a hidden file attribute. Indicates that it is assigned.

  The control unit 13 has an internal memory for storing programs defining various processing procedures and control data, and executes various processes using these. As shown in FIG. 2, the control unit 13 includes an OS execution unit 13a, a stack unit 13b, a monitoring unit 13c, a partial update unit 13d, a creation unit 13e, and a synchronization processing unit 13f.

  Among these, the OS execution unit 13a is a processing unit that controls execution of an OS that is basic software for managing the entire computer system. As an example, the OS execution unit 13a downloads and installs OS security patches and virus definition files. As another example, the OS execution unit 13a installs or uninstalls an application, and adds, deletes, or changes a user file. As a further example, the OS execution unit 13a changes the attribute of a file designated via a user interface (not shown). As described above, when a file addition, deletion, update, attribute change, or the like is executed, the OS execution unit 13a sends a file update event including the full path and update date / time of the updated file to a stack unit described later. 13b is notified. The file update event notification can be realized by using an API (Application Program Interface) provided by the OS, for example, “FindFirstChangeNotification”.

  The stack unit 13b is a processing unit that stacks updated folders on the update folder list 12a. As an aspect, when a file update event is notified from the OS execution unit 13a, the stack unit 13b determines whether a folder having the file is registered in the update folder list 12a. At this time, when the stack unit 13b is not registered in the update folder list 12a, the stack unit 13b stacks the folder on the update folder list 12a.

  A file update event stacking method will be described with reference to FIG. FIG. 5 is a diagram for explaining a file update event stacking method. In FIG. 5, it is assumed that a file update event including the full path of the file shown on the left side in the figure is notified in order from the top. Furthermore, in FIG. 5, it is assumed that a folder is not registered in the update folder list 12a at the stage when a file update event is first notified.

  As illustrated in FIG. 5, when a file update event including the full file path “D: \ A \ a1.xxx” is notified, the stack unit 13 b includes the file name “a1.xxx at the end of the full path of the file a 1. "Is deleted. By deleting the file name at the end in this way, the file A is processed into the full path “D: \ A” of the folder A having the file a1 notified of the file update event. After that, the stack unit 13b determines whether or not the folder A is registered in the update folder list 12a. In this case, since the folder is not registered in the update folder list 12a, the stack unit 13b registers the full path “D: \ A” of the folder A in the update folder list 12a.

  Thus, after the full path “D: \ A” of the folder A is registered, even if the file update event of the file a1, the file a2, and the file a3 stored in the folder A is notified, the update folder list 12a Do not register with. That is, in the example of FIG. 5, after the full path of the folder A is registered in the update folder list 12a, the full path “D: \ A \ a2.xxx” of the file a2 and the full path “D: \ A \ a3.xxx” of the file a3. Is notified. Since these are all files stored in the folder A, registration to the update folder list 12a is not executed.

  After that, when a file update event including the file full path “D: \ A \ K \ k1.xxx” is notified, the stack unit 13b deletes the last file name “k1.xxx” in the full path of the file k1. To do. By deleting the file name at the end in this way, it is processed into the full path “D: \ A \ K” of the folder K having the file k1 notified of the file update event. After that, the stack unit 13b determines whether or not the folder K is registered in the update folder list 12a. In this case, since the folder K is not registered in the update folder list 12a, the stack unit 13b registers the full path “D: \ A \ K” of the folder K in the update folder list 12a. Thereafter, the full path “D: \ A \ K \ a2.xxx” of the file k2 is notified, but since this is a file stored in the folder K, registration in the update folder list 12a is not executed.

  Further, when a file update event including the full path “D: \ B \ b1.xxx” of the file is notified, the stack unit 13b deletes the last file name “b1.xxx” in the full path of the file b1. By deleting the file name at the end in this way, the file B is processed into the full path “D: \ B” of the folder B having the file b1 notified of the file update event. After that, the stack unit 13b determines whether or not the folder B is registered in the update folder list 12a. In this case, since the folder B is not registered in the update folder list 12a, the stack unit 13b registers the full path “D: \ B” of the folder K in the update folder list 12a. Thereafter, the full path “D: \ B \ b2.xxx” of the file b2 is notified, but since this is a file stored in the folder B, registration in the update folder list 12a is not executed.

  In this way, the stack unit 13b registers the file update events notified from the OS execution unit 13a in a list, not in units of files, but in units of folders. For this reason, when a file stored in the same folder is updated, it is not necessary to register the file again in the list, so that it is possible to reduce the processing load of stacking file update events.

  The monitoring unit 13c is a processing unit that monitors the ratio of the number of updated files to the total number of files to be synchronized. The monitoring unit 13c monitors the above ratio in two different periods, the first period and the second period. In the following, the total number of files to be synchronized may be referred to as “total number of files”, and the number of updated files may be referred to as “number of updated files”.

  Among these, the first period is a monitoring time set for executing partial update of the file list 12c at a stage before the cost performance is improved by re-creating rather than partially updating the file list 12c. It is. In the first cycle, monitoring can be executed when a file update event is notified. However, when file update events are notified in a short period of time, the monitoring processing load is high. For example, a period such as a 10-second period is set. On the other hand, the second cycle is a monitoring time set to determine whether it is better to partially update or recreate the file list 12c at regular or regular times. A longer cycle, for example, a cycle such as one hour is set.

  For example, the monitoring unit 13c executes a first monitoring process for determining whether or not to partially update the file list 12c when the first period has elapsed since the previous monitoring was executed. To explain this, first, the monitoring unit 13c determines whether or not there is a stack in the update folder list 12a. At this time, when there is a stack in the update folder list 12a, the monitoring unit 13c calculates the total number of files f1 by adding up the number of files mounted in the subordinate number list 12b. Subsequently, the monitoring unit 13c calculates the updated file number f2 by totaling the number of files under the folder stacked in the updated folder list 12a among the number of files mounted in the subordinate number list 12b. After that, the monitoring unit 13c determines whether the ratio of the number of updated files f2 to the total number of files f1, that is, f2 / f1 exceeds a predetermined threshold β. At this time, if the ratio of the number of updated files f2 to the total number of files f1 exceeds the threshold value β, the partial update of the file list 12c is executed by the partial update unit 13d described later.

  In addition, the monitoring unit 13c receives a synchronization instruction from an external device such as a console, when the second period has elapsed since the previous monitoring, when a synchronization instruction is received via a user interface (not shown), or In some cases, the following processing is started. That is, the monitoring unit 13c executes a second monitoring process for determining whether to partially update or recreate the file list 12c. To explain this, the monitoring unit 13c calculates the total number of files f1 and the number of updated files f2 when there is a stack in the update folder list 12a, as in the first monitoring process. After that, the monitoring unit 13c determines whether the ratio of the number of updated files f2 to the total number of files f1, that is, f2 / f1 exceeds a predetermined threshold β. At this time, if the ratio of the number of update files f2 to the total number of files f1 exceeds the threshold value α, the file list 12c is recreated by the creation unit 13e described later. On the other hand, when the ratio of the updated file number f2 to the total file number f1 does not exceed the threshold value α, the partial update unit 13d described later performs partial update of the file list 12c.

  In this way, the monitoring unit 13c estimates the maximum number of update files by adding up the number of files under the folders stacked in the update folder list 12a among the number of files mounted in the subordinate number list 12b. . For this reason, the number of update files can be obtained without the files that have been updated leaking from the number of update files without stacking file update events in units of files.

  The partial update unit 13d is a processing unit that partially updates the file list 12c. As one aspect, the partial update unit 13d determines that the ratio of the number of updated files to the total number of files exceeds the threshold value β in the first monitoring process, or if the threshold value α does not exceed the threshold value α in the second monitoring process. The file list 12c is partially updated.

  Explaining this, the partial update unit 13d designates the full path of the folder stacked in the update folder list 12a and notifies the OS execution unit 13a of an acquisition request for a file under the folder. And the partial update part 13d will calculate the hash value of a file using a predetermined | prescribed hash function, if the file under a folder is acquired from OS execution part 13a. Thereafter, the partial update unit 13d deletes files under the folders stacked in the update folder list 12a among the files registered in the file list 12c. Then, the partial update unit 13d adds data in which the full path, size, attribute, and hash value of the file acquired from the OS execution unit 13a are associated with each other to the file list 12c. In this way, the list relating to the files under the folder stacked in the update folder list 12a is merged with the file list 12c. As a result, the file list 12c is partially updated.

  Here, the “threshold value β” is set using at least one of a system resource availability, a processor performance, and a disk access performance. That is, if the threshold value β is set to be small, the frequency at which the partial update of the file list 12c is executed increases. Thus, if the frequency with which the file list 12c is partially updated is excessively increased, the system resources of the main server 10 are constantly pressed, and the significance of executing the second monitoring process that is executed regularly or regularly is significant. getting thin. From this, the value is lower than the threshold value α used for the second monitoring process, and the value decreases as the CPU and memory usage rate of the main server 10 decreases, and the value decreases as the access speed to the disk increases. The threshold value β calculated by the threshold value β calculation algorithm determined as described above is used in the first monitoring process of the monitoring unit 13c.

  The creation unit 13e is a processing unit that creates the file list 12c. As one aspect, the creation unit 13e creates a new file list 12c when the file list 12c is not registered in the storage unit 12. As another aspect, the creation unit 13e recreates the file list 12c when the ratio of the number of updated files to the total number of files exceeds a threshold value α. Note that new creation and re-creation of the file list 12c are performed in the same manner as described below.

  Explaining this, the creation unit 13e designates the root folder located in the uppermost layer among the synchronization target folders, and sends an acquisition request for all files stored in the root folder and its lower folders to the OS execution unit 13a. Notice. In this way, the creation unit 13e acquires all files to be synchronized from the OS execution unit 13a using the folder monitoring API provided by the OS. Thereafter, the creation unit 13e calculates a hash value of the file using a predetermined hash function for each synchronization target file acquired from the OS execution unit 13a. Then, the creation unit 13e creates the file list 12c by associating the full path, size, attribute, and hash value for each synchronization target file acquired from the OS execution unit 13a. Then, when the file list 12 c is not registered in the storage unit 12, the creation unit 13 e registers the created file list 12 c in the storage unit 12. On the other hand, when the file list 12c is already registered in the storage unit 12, the creation unit 13e overwrites and saves the file list 12c recreated this time on the previously created file list.

  Here, the above “threshold value α” is the total number of files to be synchronized, the time required for merging the partial update per file into the file list 12c, or the time required for calculating the hash value per file. It is set using at least one of them.

  6 and 7 are schematic diagrams of graphs showing the relationship between the time required for creating the file list 12c and the number of updated files. 6 and 7, the vertical axis of the graphs in the drawings indicates the time required for creating the file list 12c, and the horizontal axis of the graphs in the drawings indicates the number of update files. Also, the alternate long and short dash line 60 shown in FIG. 6 shows a graph of the time required to recreate the file list 12c. Furthermore, the solid line 61 shown in FIG. 6 shows a graph of the time required for partial update of the file list 12c. In addition, an alternate long and short dash line 70 shown in FIG. Also, a two-dot chain line 71 shown in FIG. 7 shows a graph of a partial update required time including a hash value calculation required time.

  As shown in FIG. 6, the re-creation of the file list 12c depends only on the total number of files to be synchronized. Therefore, in the re-creation required time graph 60, the required time is always constant regardless of the number of update files. On the other hand, in the partial update required time graph 61, the required time increases as the number of update files increases.

  When re-creating the file list 12c, the list data created this time is merged after deleting the previously created list data for the files under the folder registered in the update folder list 12a. The For this reason, when the file list 12c is partially updated, since the list data of the files under the folder registered in the update folder list 12a is deleted, the file list 12c is more per file than when the file list 12c is recreated. The required time becomes longer. Therefore, depending on the number of update files, the partial update required time graph 61 may exceed the re-creation required time graph 60.

From this, the number of update files at the intersection of the re-creation required time graph 60 and the partial update required time graph 61 is obtained from the merge required time per file and then synchronized with the update file number f _α1 at the intersection. The threshold value α can be calculated from the total number of target files. When this threshold value α is employed, the file list 12c can be partially updated by the partial update unit 13d until the partial update required time graph 61 intersects with the re-creation required time graph 60. Further, when the partial update required time graph 61 exceeds the re-creation required time graph 60, the creation unit 13e can re-create the file list 12c. Therefore, by adopting the threshold value α, it is possible to adaptively control partial update or recreation of the file list 12c.

  Furthermore, when the hash value of the file is included in the file list 12c in order to check the identity of the file, it is preferable to set the threshold α by including the time required for calculating the hash value as a parameter. This is because the time required for calculating the hash value is very long compared to the time required for merging, and as shown in FIG. 7, the calculation of the hash value is compared with the graph 60 of the time required for partial update when the hash value is not calculated. This is because the slope of the partial update required time graph 71 including the required time becomes small. Along with this, the intersection of the graph 70 of the required time for re-creation and the graph 71 of the required time for partial update including the required time for calculating the hash value is also shifted to the right.

Therefore, when calculating the hash value of a file, the number f _α2 of updated files at the intersection of the two graphs is calculated from the time required for merging per file and the time required for calculating the hash value per file. To do. In addition, it is preferable to calculate the threshold value α _H from the updated file number f _α2 and the total number of files to be synchronized. When such a threshold value α _H is adopted, partial update or recreation of the file list 12c can be adaptively controlled even when the hash value of the file is included in the file list 12c.

  The synchronization processing unit 13f is a processing unit that executes a synchronization process for matching data held between the plurality of sub servers 30A to 30C. As one aspect, when the second monitoring process is executed, the synchronization processing unit 13f displays the file list 12c partially updated by the partial update unit 13d or the file list 12c recreated by the creation unit 13e as a sub-server. Transfer to 30. Thereafter, the synchronization processing unit 13f transmits the difference file detected between the two file lists created by the main server 10 and the sub servers 30A to 30C to the sub server 30. By storing the difference file in the sub server 30, the contents of the data held by the main server 10 and the sub server 30 are matched.

[Process flow]
Next, the flow of processing of the main server 10 according to the present embodiment will be described. Here, (1) the stack process is described, (2) the first monitoring process is described, and finally (3) the second monitoring process is described.

(1) Stack Processing FIG. 8 is a flowchart illustrating a procedure of stack processing according to the first embodiment. This stack process is a process that is repeatedly executed as long as the main server 10 is powered on.

  As shown in FIG. 8, when a file update event is notified from the OS execution unit 13a (Yes in step S101), the stack unit 13b executes the following process. In other words, the stack unit 13b specifies the full path of the folder under which the file notified of the file update event is deleted by deleting the last file name from the full path of the file (step S102).

  Thereafter, the stack unit 13b determines whether or not the folder having the file under control has been stacked in the update folder list 12a (step S103). At this time, if the folder is not stacked on the update folder list 12a (No at Step S103), the stack unit 13b stacks the folder on the update folder list 12a (Step S104), and returns to Step S101.

  On the other hand, if the folder has been stacked on the update folder list 12a (Yes at step S103), the process returns to step S101 without executing the stack on the update folder list 12a.

(2) First Monitoring Process FIG. 9 is a flowchart illustrating the procedure of the first monitoring process according to the first embodiment. The first monitoring process is started when a first period, for example, 10 seconds has elapsed since the first monitoring process was executed last time.

  As shown in FIG. 9, first, the monitoring unit 13c determines whether or not there is a stack in the update folder list 12a (step S201). If there is no stack in the update folder list 12a (No in step S201), the file list 12c does not need to be partially updated or recreated, so the process is terminated.

  At this time, when there is a stack in the update folder list 12a (Yes at Step S201), the monitoring unit 13c calculates the total number of files f1 by adding up the number of files mounted in the subordinate number list 12b (Step S202). .

  Subsequently, the monitoring unit 13c calculates the updated file number f2 by totaling the number of files held by the folders stacked in the updated folder list 12a among the number of files mounted in the subordinate number list 12b ( Step S203).

  Then, the monitoring unit 13c determines whether or not the ratio of the number of updated files f2 to the total number of files f1, that is, f2 / f1 exceeds a predetermined threshold value β (step S204).

  Here, when the ratio of the number of updated files f2 to the total number of files f1 exceeds the threshold β (Yes in step S204), the partial update unit 13d sets the file list 12c for the folders stacked in the updated folder list 12a. Partial update is performed (step S205).

  Thereafter, the partial update unit 13d updates the subordinate number of the folder in which the file list 12c is partially updated in the subordinate number list 12b to the number of files after the partial update (step S206). Furthermore, the partial update unit 13d clears the update folder list 12a (step S207) and ends the process.

  If the ratio of the number of updated files f2 to the total number of files f1 does not exceed the threshold β (No in step S204), the file list 12c does not need to be partially updated, and the process ends.

(3) Second Monitoring Process FIG. 10 is a flowchart illustrating the procedure of the second monitoring process according to the first embodiment. This second monitoring process is performed when a second cycle, for example, 1 hour has elapsed since the second monitoring process was executed last time, when a synchronization instruction is received via a user interface (not shown), or when a console is used. The process is started when a synchronization instruction is received from an external device.

  As shown in FIG. 10, first, the monitoring unit 13c determines whether or not there is a stack in the update folder list 12a (step S301). If there is no stack in the update folder list 12a (No at Step S301), the file list 12c does not need to be partially updated or recreated, and the process is terminated.

  At this time, if there is a stack in the update folder list 12a (Yes at Step S301), the monitoring unit 13c calculates the total number of files f1 by adding up the number of files mounted in the subordinate number list 12b (Step S302). .

  Subsequently, the monitoring unit 13c calculates the updated file number f2 by totaling the number of files held by the folders stacked in the updated folder list 12a among the number of files mounted in the subordinate number list 12b ( Step S303).

  Then, the monitoring unit 13c determines whether or not the ratio of the updated file number f2 to the total file number f1, that is, f2 / f1 exceeds a predetermined threshold value α (step S304).

  Here, when the ratio of the number of updated files f2 to the total number of files f1 exceeds the threshold value α (Yes in step S304), the creation unit 13e takes more time to partially update the file list 12c. It is recreated (step S305).

  Thereafter, the creation unit 13e updates the subordinate number of each folder registered in the subordinate number list 12b to the number of files after re-creation (step S306). Furthermore, the creation unit 13e clears the update folder list 12a (step S307) and ends the process.

  On the other hand, if the ratio of the number of updated files f2 to the total number of files f1 does not exceed the threshold α (No in step S304), the partial update unit 13d sets the file list 12c for the folders stacked in the updated folder list 12a. Partial update is performed (step S308).

  Thereafter, the partial update unit 13d updates the subordinate number of the folder in which the file list 12c is partially updated in the subordinate number list 12b to the number of files after the partial update (step S306). Furthermore, the partial update unit 13d clears the update folder list 12a (step S307) and ends the process.

[Effect of Example 1]
As described above, when the main server 10 according to the present embodiment performs synchronization processing with the sub server 30 using a file list, a portion of the file list according to the ratio of the number of updated files to the total number of files. Adaptively control update or recreation. For example, in the main server 10 according to the present embodiment, when the update of the file to be synchronized is limited to a part of the file list 12c, the file list 12c is partially updated while the file list 12c is entirely updated. Can recreate the file list 12c. Therefore, according to the main server 10 according to the present embodiment, the file list creation time can be shortened.

  Although the embodiments related to the disclosed apparatus have been described above, the present invention may be implemented in various different forms other than the above-described embodiments. Therefore, another embodiment included in the present invention will be described below.

[Scope of application]
For example, in the first embodiment described above, the case where the file list of the main server 10 is created is illustrated, but the disclosed apparatus is not limited to this. For example, when the sub server 30 creates a file list by mounting the functional units of the stack unit 13b, the monitoring unit 13c, the partial update unit 13d, and the creation unit 13e shown in FIG. The invention can be applied.

  In the first embodiment, the file synchronization method between the main server 10 and the plurality of sub servers 30 has been described. However, different computers do not necessarily have to hold files to be synchronized. That is, the disclosed apparatus can be similarly applied when synchronizing files between a plurality of file systems, for example, when a plurality of or different file systems are mounted on one computer. For example, the disclosed apparatus can be applied to a case where files are synchronized between file systems possessed by computers equipped with a plurality of virtual machines, or when a file is synchronized between file systems possessed by a disk server. It can also be applied.

  In the first embodiment, the case where the file list used for the synchronization process is created is illustrated. However, the disclosed apparatus is not limited to this, and other processes such as creating a backup data file list are accelerated. The same applies to the case.

[Distribution and integration]
In addition, each component of each illustrated apparatus does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution / integration of each device is not limited to that shown in the figure, and all or a part thereof may be functionally or physically distributed or arbitrarily distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured. For example, the stack unit 13b, the monitoring unit 13c, the partial update unit 13d, or the creation unit 13e may be connected as an external device of the main server 10 via a network. In addition, the stack unit 13b, the monitoring unit 13c, the partial update unit 13d, or the creation unit 13e are provided in different devices, and are connected to the network to cooperate to realize the function of the main server 10 described above. Also good.

[Synchronization program]
The various processes described in the above embodiments can be realized by executing a prepared program on a computer such as a personal computer or a workstation. In the following, an example of a computer that executes a synchronization program having the same function as that of the above embodiment will be described with reference to FIG.

  FIG. 11 is a schematic diagram illustrating an example of a computer that executes a synchronization program according to the first and second embodiments. As illustrated in FIG. 11, the computer 100 includes an operation unit 110 a, a speaker 110 b, a camera 110 c, a display 120, and a communication unit 130. Further, the computer 100 includes a CPU 150, a ROM 160, an HDD 170, and a RAM 180. These units 110 to 180 are connected via a bus 140.

  As shown in FIG. 11, the HDD 170 stores in advance a synchronization program 170a that performs the same functions as the stack unit 13b, the monitoring unit 13c, the partial update unit 13d, and the creation unit 13e described in the first embodiment. . The synchronization program 170a may be integrated or separated as appropriate, like the respective components of the stack unit 13b, the monitoring unit 13c, the partial update unit 13d, and the creation unit 13e shown in FIG. In other words, all data stored in the HDD 170 need not always be stored in the HDD 170, and only data necessary for processing may be stored in the HDD 170.

  Then, the CPU 150 reads the synchronization program 170 a from the HDD 170 and expands it in the RAM 180. Thus, as shown in FIG. 11, the synchronization program 170a functions as a synchronization process 180a. The synchronization process 180a expands various data read from the HDD 170 in an area allocated to itself on the RAM 180 as appropriate, and executes various processes based on the expanded data. The synchronization process 180a includes processing executed by the stack unit 13b, the monitoring unit 13c, the partial update unit 13d, and the creation unit 13e illustrated in FIG. 2, for example, the processing illustrated in FIGS. In addition, each processing unit virtually realized on the CPU 150 does not always require that all processing units operate on the CPU 150, and only a processing unit necessary for the processing needs to be virtually realized.

  Note that the synchronization program 170a is not necessarily stored in the HDD 170 or the ROM 160 from the beginning. For example, each program is stored in a “portable physical medium” such as a flexible disk inserted into the computer 100, so-called FD, CD-ROM, DVD disk, magneto-optical disk, or IC card. Then, the computer 100 may acquire and execute each program from these portable physical media. In addition, each program is stored in another computer or server device connected to the computer 100 via a public line, the Internet, a LAN, a WAN, etc., and the computer 100 acquires and executes each program from these. It may be.

DESCRIPTION OF SYMBOLS 1 Data distribution system 10 Main server 11 Communication I / F part 12 Storage part 12a Update folder list 12b Subordinate number list 12c File list 13 Control part 13a OS execution part 13b Stack part 13c Monitoring part 13d Partial update part 13e Creation part 13f Synchronization process Part 30A, 30B, 30C Subserver

Claims (6)

A synchronization method between different file systems,
Computer
Create a file list in advance for the files to be synchronized,
Get an event about update of the file,
When the folder having the file from which the event is acquired is not stored in the update folder storage unit that stores the updated folder, the folder is registered in the update folder storage unit,
Estimating the maximum number of update files based on the number of files under the folder stored in the update folder storage unit,
When the ratio of the maximum number of updated files to the total number of files to be synchronized exceeds the first threshold, the file list is partially updated,
When the ratio of the maximum number of updated files to the total number of files to be synchronized exceeds a second threshold value that is larger than the first threshold value, the file list is re-created instead of partially updating the file list. The synchronization method characterized by performing. The previous Symbol file list as a process of partial update,
If the ratio of maximum update number of files relative to the total number of files to be synchronized has exceeded the first threshold value, the process of updating the file list by folder targeting folders stored in the update folder storage unit The synchronization method according to claim 1, wherein the synchronization method is executed.   The second threshold value is at least one of the total number of files to be synchronized, the time required for merging a partial update per file into the file list, or the time required for calculating a hash value per file. The synchronization method according to claim 1, wherein the synchronization method is a setting value set by using the method.   The first threshold value is a setting value that is set using at least one of system resource availability, processor performance, and disk access performance. Synchronization method. A synchronization program for executing a synchronization method between different file systems,
On the computer,
Create a file list in advance for the files to be synchronized,
Get an event about update of the file,
When the folder having the file from which the event is acquired is not stored in the update folder storage unit that stores the updated folder, the folder is registered in the update folder storage unit,
Estimating the maximum number of update files based on the number of files under the folder stored in the update folder storage unit,
When the ratio of the maximum number of updated files to the total number of files to be synchronized exceeds the first threshold, the file list is partially updated,
When the ratio of the maximum number of updated files to the total number of files to be synchronized exceeds a second threshold value that is larger than the first threshold value, the file list is re-created instead of partially updating the file list. A synchronization program characterized by causing An information processing apparatus that performs file synchronization processing between different file systems,
A creation unit that creates a file list in advance for a file to be synchronized; an acquisition unit that acquires an event related to the update of the file;
When the folder having the file from which the event is acquired is not stored in the update folder storage unit that stores the updated folder, the registration unit that registers the folder in the update folder storage unit;
A calculation unit that estimates the maximum number of update files based on the number of files under the folder stored in the update folder storage unit;
A partial update unit that partially updates the file list when the ratio of the maximum number of update files to the total number of files to be synchronized exceeds a first threshold;
When the ratio of the maximum number of updated files to the total number of files to be synchronized exceeds a second threshold value that is larger than the first threshold value, the file list is not re-updated but re-created to re-create the file list. An information processing apparatus comprising: a creation unit.

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