JP2009187324A - File keeping device, file keeping method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a file keeping device capable of storing data temporarily with exceeded contract capacity without generating excessive charging to a user and capable of suppressing the cost of equipment investment. <P>SOLUTION: The file keeping device comprises: a first data storage part 14 securing a contract area 22 wherein one, two or more files can be preserved and deleted in the range of a predetermined contract capacity; a second data storage part 15 provided separately from the first data storage part; a management information storage part storing the contract capacity; and a storage information control part for preparing an additional storage area in the second data storage part if the total capacity of the one, two or more files stored in the contract area exceeds the contract capacity when a file is added to the contract area. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an application service provider (ASP) that provides an area for storing a file to a user through a network, and particularly relates to an ASP (such as a rental storage service) that provides such an area as a business.

  As one of services provided by ASP on the Internet, there are a rental storage service, a hosting service (so-called rental server), and the like. In these services, when a user uses the service, a user area where files can be saved by the service and a contract capacity which is a total capacity of files which can be saved in the user area are determined in advance.

  As a technique related to this, there is a patent document as described below. Japanese Patent Application Laid-Open No. 2004-228561 describes a technique for charging a pay-as-you-go system according to storage size and storage time for digital content data storage. Patent Document 2 describes an example of a method for charging for viewing of content via a network. Japanese Patent Application Laid-Open No. 2004-228561 describes a technique of charging based not only on the size of the storage usage area but also on the overall usage status of the storage.

  Patent Document 4 describes a technique of charging for content viewing via a network based on reproduction time or information amount. In Patent Document 5, when the capacity stored in the local drive exceeds a predetermined threshold between the network storage and the local drive, the data is transferred to the network drive. A technique for moving data is described.

  Patent Document 6 describes a technique in which a storage location is determined from data storage locations of different quality and fee according to the importance of data, and storage and charging are performed. Patent Document 7 describes a technique of charging based on the access speed for data stored in a storage.

JP 2001-306831 A JP 2001-357222 A JP 2002-236852 A JP 2003-167585 A JP 2004-110290 A JP 2006-113694 A JP 2006-113824 A

  In such rental storage services, it is usually impossible to store files exceeding the contracted capacity, or an excess charge is charged according to the capacity exceeding the contracted capacity. This excess charge can be unexpectedly expensive.

  The service disclosed in Patent Document 1 does not define the upper limit capacity that can be used by the user, and has a mechanism for charging only the amount used, so that the user will not be able to accumulate data. However, since it is a pay-per-use charge according to the storage size and the storage time, the charge may be unexpectedly high by storing a large amount of data for a long period of time. The service of Patent Document 6 also has the same problem as Patent Document 1 because the capacity that can be used by the user is not defined.

  In the services of Patent Documents 1 and 6, since there is no consideration about the upper limit capacity that can be used by the user, data can be accumulated up to the entire capacity in the storage device prepared by the ASP. There is also a problem that the service itself is stopped or a problem such as an adverse effect on other users is caused. On the ASP side, sufficient capital investment for a storage device such as a magnetic disk is required in order to allow the user to accumulate data exceeding the contracted capacity and not to stop the service.

  However, a storage device prepared for this purpose needs to have a low risk of data loss or damage over a long period of time and can be read and written at high speed by a user. Therefore, it is necessary to use a high-performance storage device having high speed of data reading / writing and high reliability provided with a measure for protecting data stored. However, since a high-performance storage device has a high unit price per unit storage capacity, the cost for preparing a large storage capacity is enormous.

  Incidentally, the service of Patent Document 5 merely moves data between a storage on a network and a local drive, and does not have a configuration for solving the above-described problem. Other than those, Patent Documents 2 to 4 and 7 do not have a configuration for solving the above-described problem.

  An object of the present invention is to provide a file storage device capable of temporarily exceeding the contract capacity and storing data and suppressing the cost of capital investment in an ASP without causing excessive charging to the user. Another object is to provide a file storage method and program.

  In order to achieve the above object, a file storage apparatus according to the present invention is a file storage apparatus capable of storing and deleting files, and storing and deleting a single file and a plurality of files within a predetermined contracted capacity range. A first data storage unit in which a contract area that can be secured is secured, a second data storage unit provided separately from the first data storage unit, and a file can be added to the contract area When the management information storage unit that stores the contract area free capacity that is the capacity and a file with a capacity that exceeds the contract area free capacity is about to be added to the contract area, an additional storage area is created in the second data storage unit And an accumulated information control unit.

  In order to achieve the above object, a file archiving method according to the present invention is a method for archiving a file in a file archiving apparatus having a first data storage unit and a second data storage unit. A contract area securing process that secures a contract area where one or more files can be saved and deleted within the contract capacity range predetermined in the department, and a contract that is a capacity that can add files to the contract area A contract area free capacity storing step for storing area free capacity, a first file capacity determining step for determining whether or not the capacity of a file to be added to the contract area exceeds the contract area free capacity, And an additional storage area creation step of creating an additional storage area in the second data storage unit when the file capacity exceeds the contract area empty capacity in the file capacity determination step. The features.

  In order to achieve the above object, a file archiving program according to the present invention is pre-determined in a first data storage unit in a computer that controls a file archiving apparatus having a first data storage unit and a second data storage unit. Contract area reservation processing that secures a contract area that can store and delete single and multiple files within the specified contract capacity range, and the contract area empty capacity that can add files to the contract area Contract area free capacity storage process to be stored, first file capacity determination process to determine whether the capacity of a file to be added to the contract area exceeds the contract area free capacity, and first file capacity determination process If the file capacity exceeds the contract area free space, the second data storage unit executes additional storage area creation processing for creating an additional storage area And wherein the door.

  Since the present invention is configured to create the additional storage area in the second data storage unit different from the first data storage unit when the contracted capacity is about to be exceeded, the second data storage unit is provided in the second data storage unit. The unit price per unit storage capacity can be lower than that of one data storage unit. As a result, it is possible for ASP to temporarily exceed the contract capacity without accumulating excessive charges to the user and accumulate data, and to reduce the cost of capital investment, which is unprecedented. File storage device, file storage method, and program can be provided.

[First Embodiment]
FIG. 1 is a functional block diagram showing a configuration of a file storage apparatus 10 according to the first embodiment of the present invention. The file storage device 10 is configured by a computer device that is connected to the network 20 and includes a data storage device such as a disk device. The file archiving apparatus 10 includes functional blocks of an accumulation information control unit 11, a management information storage unit 12, a control program storage unit 13, a high performance data storage unit 14, and a low performance data storage unit 15. Each detailed configuration will be described later.

  The accumulated information control unit 11 is a main part of a computer that executes an operation according to the present embodiment to be described later, and executes a program read from the control program storage unit 13. The management information storage unit 12 stores data about each user and each storage device (collectively referring to the high-performance data storage unit 14 and the low-performance data storage unit 15) necessary for the operation of the accumulated information control unit 11. To do.

  The high-performance data storage unit 14 and the low-performance data storage unit 15 are data storage devices configured by a magnetic disk device, an optical disk device, or the like. “Performance” as used herein is a concept that combines high-speed data reading and writing and reliability of stored data. In particular, emphasis is placed on the level of protection of stored data. Of course, the higher the unit price per unit storage capacity, the higher the performance.

  The high-performance data storage unit 14 is connected to an expensive disk device connected by a high-performance interface such as Fiber Channel or SCSI, and further has a low capacity efficiency such as RAID-1 or RAID-10, but at the time of failure. The company has also implemented data protection measures that do not reduce the transfer speed. On the other hand, the low-performance data storage unit 15 has a high capacity efficiency, such as RAID-5, in an inexpensive disk device connected by a low-performance interface such as ATA, but there is a decrease in transfer speed in the event of a failure. Take data protection measures or do not take such measures.

  On the other hand, a client device 21 such as a mobile phone, a mobile terminal, a desktop PC, or a large computer is connected to the network 20, and a rental storage service provided by the file storage device 10 is used from these terminals via the network 20. can do.

  FIG. 2 is a conceptual diagram showing an image of a rental storage service (hereinafter simply referred to as a service) provided by the file storage device 10 shown in FIG. When the user contracts for the service, storage for the contracted storage capacity (hereinafter referred to as contract capacity) is allocated as the contract area 22.

  The user can access the contract area 22 from the client device 21 via the network 20. As a matter of course, the contract area 22 of other users who use the same service cannot be accessed in principle (depending on the contents of the contract, access may be permitted with restrictions).

  FIG. 3 is a conceptual diagram showing an operation of creating the additional storage area 23 in the file storage device 10 shown in FIG. The high performance data storage unit 14 includes a plurality of high performance disk devices 34. The low performance data storage unit 15 includes a plurality of low performance disk devices 35. The high-performance data storage unit 14 includes a contract area 22 assigned when a user contracts for a service.

  On the other hand, when data that temporarily exceeds the contracted capacity is stored, an additional storage area 23 corresponding to the capacity exceeding the contracted capacity is temporarily created. The additional storage area 23 is realized by creating an area for the insufficient capacity from the low-performance data storage unit 15 and additionally assigning it.

  FIG. 4 is a conceptual diagram showing an operation when data exceeding the contracted capacity is stored in the file storage device 10 shown in FIG. FIG. 4A shows a state in which the first user data 41 having a capacity not exceeding the contract capacity is stored in the contract area 22. From this state, the second user data 42 is added to the contract area 22 and stored. Even if the capacities of the first user data 41 and the second user data 42 are combined, the contract capacity is not yet exceeded.

  In this case, as shown in FIG. 4B, the first user data 41 and the second user data 42 are continuously stored in the contract area 22. At this time, there is a free capacity that is equivalent to the total capacity of the first user data 41 and the second user data 42 subtracted from the contract capacity.

  Here, the third user data 43 having a capacity exceeding the free capacity is additionally stored. Therefore, as shown in FIG. 4C, an additional storage area 23 having a capacity corresponding to the capacity that is insufficient, that is, the capacity obtained by subtracting the free capacity from the capacity of the third user data 43 is created. As a result, as shown in FIG. 4D, the first user data 41 and the second user data 42 are further followed by the third user data 43 so that the contract area 22 and the additional storage area 23 are stored. It is stored in the combined area. As described above, at the time of data registration, each data is always arranged continuously in the storage.

  FIG. 5 is a conceptual diagram showing an operation in which the additional storage area 23 is released by deleting unnecessary data in the file storage apparatus 10 shown in FIG. 5A, similarly to FIG. 4D, the first to third user data 41 to 43 are continuously stored in the area including the contract area 22 and the additional storage area 23. Indicates the state. Here, it is considered that the second user data 42 is deleted. Since the total capacity of the first user data 41 and the third user data 43 is less than the contract capacity, it is a capacity that can be stored only in the contract area 22 without using the additional storage area 23.

  In this case, as shown in FIG. 5B, the third user data 43 is moved to an area freed by deleting the second user data 42 in the contract area 22. The third user data 43 is in a state continuous with the first user data 41. By doing so, as shown in FIG. 5C, there is no data in the additional storage area 23, so the additional storage area 23 is returned to the low performance data storage unit 15, and FIG. As shown, only the contract area 22 is used.

  Here, when the total capacity of the first user data 41 and the third user data 43 exceeds the contract capacity, the additional storage area 23 cannot be returned. However, in this case as well, if the second user data 42 is deleted, the third user data 43 is moved and is in a state continuous with the first user data 41. The same applies when the additional storage area 23 is not originally used. It is a rule in this embodiment that each data is always arranged continuously in the storage.

  FIG. 6 is a conceptual diagram showing an operation of updating data in the file storage device 10 shown in FIG. FIG. 6A shows a state in which the first to third user data 41 to 43 are continuously stored in the contract area 22. Here, it is considered that the second user data 42 is deleted and the fourth user data 44 is stored. That is, the second user data 42 is updated to become fourth user data 44. Also in this case, first, the second user data 42 is deleted as shown in FIG. 6 (b), and the third user data 43 is moved to an vacant area as shown in FIG. 6 (c). The first user data 41 is in a continuous state. In addition, as shown in FIG. 6D, fourth user data 44 is stored so as to be continuous with the third user data 43.

  In this case, the operation is the same whether in the contract area 22 or in the area where the contract area 22 and the additional storage area 23 are combined. When a need arises due to a change in storage capacity, an operation for adding or releasing the additional storage area 23 shown in FIGS. 4 and 5 may be performed.

  FIG. 7 is a conceptual diagram showing the configuration of the file management information 101 in the file storage apparatus 10 shown in FIG. The contract area 22 and the additional storage area 23 are collectively referred to as a user area 100. The file management information 101 for the user area 100 is stored in the management information storage unit 12.

  Now, it is assumed that N pieces of user data 41a to (file (1) to file (N)) are stored in the user area 100. The corresponding file management information 101 includes a disk ID 111 indicating the identifier of the disk device in which the user area 100 exists, a stored file number 112 indicating the number N of files stored in the user area 100 by the user, and each user data It consists of an identifier 121, a storage location start address 122, and a data size 123 given for each (file (1) to file (N)).

  Thereafter, the identifier 121, the storage location start address 122, and the data size 123 for the file (n) that is the nth user data 41a to... In the file management information 101 are respectively represented by the identifier (n) and the storage location start address ( n) and data size (n). (N and N are natural numbers and 1 ≦ n ≦ N)

  FIG. 8 is a functional block diagram showing the configuration of the file storage apparatus 10 shown in FIG. 1 in more detail. The storage information control unit 11 includes, as hardware, a CPU 211, a communication control device 212, a first temporary storage memory 213, a second temporary storage memory 214, an internal clock 215, a RAID control device 216, and a virtual storage area management table 217. Consists of.

  The communication control device 212 is an interface for a program executed by the CPU 211 to access the network 20. The RAID control device 216 is an interface for a program executed by the CPU 211 to access the high performance data storage unit 14 and the low performance data storage unit 15.

  The first temporary storage memory 213 is a temporary storage memory that temporarily stores data transferred between the CPU 211 and the communication control device 212. The second temporary storage memory 214 is a temporary storage memory that temporarily stores data transferred between the CPU 211 and the RAID control device 216. These temporary storage memories 213 and 214 are preferably implemented by a large capacity inexpensive DRAM.

  The virtual storage area management table 217 stores information created by the RAID controller 216, and is preferably implemented by a non-volatile memory for high-speed access and relatively long-term data storage.

  As described above, the high-performance data storage unit 14 includes a plurality of high-performance disk devices 34. The low performance data storage unit 15 includes a plurality of low performance disk devices 35. The contract area 22 and the additional storage area 23 are accumulated in a continuous area from the viewpoint of the user, but the contract area 22 is actually stored in the high-performance data storage unit 14 and the additional storage area 23 is stored in the low-performance data area. It is stored in the storage unit 15.

  For this reason, the virtual storage area management table 217 stores the storage areas of the contract area 22 and the additional storage area 23 viewed from the user, and the high performance data storage section 14 and the low performance data storage section 15 where they are actually stored. Memorize the correspondence.

  Although described in detail later, the internal clock 215 is used to measure the time that the user has used the additional storage area 23.

  The management information storage unit 12 stores the file management information 101 and the billing information 300 for each user in association with the disk ID 111 as a key. High-speed access and relatively long-term data storage In order to add capacity in the future, it is preferably implemented by a non-volatile memory or a high-performance disk device 103.

  The control program storage unit 13 stores a program 231 that executes processing shown in the following description in the CPU 211, for high-speed access, relatively long-term data storage, and maintenance of the stored program. Preferably implemented by non-volatile memory.

  When the request from the client device 21 reaches the stored information control unit 11 through the communication line from the network 20 to the file storage device 10 having the configuration described above, the communication control device 212 analyzes the content of the request, After the data is stored in the first temporary storage memory 213, the CPU 211 is requested to process the request.

  Based on this request, the CPU 211 sequentially reads data stored in the first temporary storage memory 213, analyzes the request, reads the necessary program 231 from the control program storage unit 13, and obtains user information corresponding to the request. Read from the management information storage unit 12 and perform processing. At this time, the file management information 101 and the billing information 300 in the management information storage unit 12 are changed as necessary. In response to the request, the CPU 211 issues a write request to the storage apparatus to the RAID control apparatus 216. The second temporary storage memory 214 is used for data transfer at this time.

  FIG. 9 is a conceptual diagram showing a data structure of billing information 300 shown in FIG. The billing information 300 includes customer ID 301, customer name 302, customer address 303, contract capacity 304, extended area maximum capacity 305, contract capacity excess grace time 306, contact e-mail address 307, contract start as information representing each user. Date 308 and the like are included.

  Of these, the contract capacity 304 is the capacity of the contract area 22. The expansion area maximum capacity 305 is the maximum capacity of the additional storage area 23 permitted based on the contract. The additional storage area 23 exceeding this capacity cannot be created. The contract capacity excess grace time 306 is the maximum value of the time allowed to use the additional storage area 23, and is set based on the contract conditions such as “within a total of 72 hours per month”, for example. . For users who use the additional storage area 23 beyond this, for example, as a penalty, an amount corresponding to a period exceeding the contract capacity excess grace time 306 is charged (hereinafter, such charging is referred to as extended charging), etc. Can take measures.

  In addition, the billing information 300 includes, as information indicating the usage status of the service of each user, a contract area disk ID 309, a contract area free capacity 310, an additional storage area disk ID 311, an additional storage area free capacity 312, an over capacity flag 313, An extended charging flag 314, an accumulated excess time 315, an excess occurrence date and time 316, an update date and time 317, and the like are included.

  The contract area disk ID 309 is an identifier representing the contract area 22 assigned based on the contract, and corresponds to the disk ID 111 included in the file management information 101. The contract area free capacity 310 is a free capacity for the contract capacity 304 in the contract area 22 represented by the contract area disk ID 309. The additional storage area disk ID 311 is an identifier representing the additional storage area 23 added to the contract area 22. The additional storage area free space 312 is a free capacity with respect to the extended area maximum capacity 305 of the additional storage area 23 represented by the additional storage area disk ID 311.

  The excess capacity flag 313 and the extended charging flag 314 are Boolean variables. The capacity excess flag 313 is Yes if the additional storage area 23 is allocated, and No otherwise. The extended charging flag 314 is Yes when the additional storage area 23 is used beyond the contract capacity excess grace time 306, that is, when extended charging is required, and No otherwise. The accumulated excess time 315 represents the accumulated time during which the additional storage area 23 is used within the accounting target period. The excess occurrence date and time 316 represents the date and time when the additional storage area 23 was allocated most recently. The update date and time 317 represents the date and time when these data were updated most recently.

  By having such billing information 300, the occupied capacity of the contract area 22 and the additional storage area 23 becomes obvious for each user. It is possible to easily detect that the problem has been resolved and to perform an operation corresponding to it.

  FIG. 10 shows the processing performed by the program 231 for the file management information 101 when the user requests data registration to the user area 100 via the client device 21 in the file storage device 10 shown in FIGS. It is a flowchart showing. Here, from the state where N files (1) to (N) are stored in the user area 100, a file (N + 1) which is N + 1th data is newly added.

  When the execution starts, the number N of files registered in the stored file number 112 is updated to N + 1 (step S401), the identifier (N + 1) of the file (N + 1), the storage location start address (N + 1), and the data size (N + 1) ) Is added to the file management information 101 (steps S402 to 404). Thereafter, the actual data of the file (N + 1) is accumulated in the user area 100 (step S405), and the process is terminated.

  FIG. 11 shows processing performed by the program 231 for the file management information 101 when the user requests the user area 100 to delete data via the client device 21 in the file storage device 10 shown in FIGS. It is a flowchart showing. Here, from the state where N files (1) to (N) are stored in the user area 100, the file (M), which is the Mth data, is deleted. (M is a natural number and 1 ≦ M ≦ N)

  When the execution is started, the file (M + 1) that is the next file (M) in the user area 100 is first moved by the data size of the deleted file (M) (step S451). Subsequently, the identifier (M) is overwritten with the identifier (M + 1) (step S452), the storage position head address (M) is overwritten with the value after being moved in step S451 (step S453), and the data size (M) is changed to data. Overwriting is performed with the size (M + 1) (step S454).

  Thereafter, the value of M is increased by 1 (step S455), and it is determined whether or not the value of M has reached N (step S456). If it has reached, the process proceeds to step S457 and thereafter, and if not, the process returns to step S451. By repeating the steps S451 to S456, the file (M) to be deleted is overwritten.

  If the value of M has reached N in step S456, the identifier (N), storage location head address (N), and data size (N) are deleted (steps S457 to 459), and the value of the number of stored files 112 N is updated to N-1 (step S460), and the process ends.

  In the case of updating data, after the data before update is deleted by the process shown in FIG. 11, the data after update is added by the process shown in FIG.

  FIG. 12 is a flowchart showing processing performed by the program 231 for the billing information 300 during the data registration processing shown in FIG. First, after confirming the data size (N + 1) which is the capacity of the newly registered file (N + 1) (step S501), the capacity excess flag 313, the contract area free capacity 310 and the additional storage area recorded in the billing information 300 are checked. The free capacity 312 is confirmed (step S502). At this stage, the data size (N + 1) is not yet registered in the file management information 101, but here the capacity of the file (N + 1) is referred to as the data size (N + 1) for convenience.

  Then, it is determined whether or not the capacity excess flag 313 is Yes (step S503). If the excess capacity flag 313 is Yes, the additional storage area 23 is currently allocated, and the process proceeds to step S531 described later. If the excess capacity flag 313 is No, the additional storage area 23 is not currently allocated, and the process proceeds to step S504.

  If the additional storage area 23 is not currently allocated, it is determined whether or not the data size (N + 1) confirmed in step S501 is larger than the contract area free capacity 310 (step S504). If the data size (N + 1) is larger than the contract area free space 310, it is necessary to newly allocate the additional storage area 23, so the process proceeds to step S521. If the data size (N + 1) is within the contract area free space 310, it is not necessary to allocate the additional storage area 23, so the process proceeds to step S511.

  If the process proceeds to step S511 as determined in steps S503 to S504, it means that the additional storage area 23 is not currently allocated and it is not necessary to allocate the additional storage area 23 after the file (N + 1) is registered. In this case, the current time is acquired from the internal clock 215 (step S511), the value of the contract area free space 310 is updated to a value obtained by subtracting the data size (N + 1) from the current value (step S512), and the update date and time 317. Is updated to the time acquired in step S511 (step S513). In step S551, the data registration process shown in FIG. 10 is executed.

  If the process proceeds to step S521 based on the determination in steps S503 to S504, it means that the additional storage area 23 is not currently allocated, but the file (N + 1) cannot be registered with the contract area free space 310 alone. In this case, it is determined whether or not the data size (N + 1) is larger than the sum of the contract area free capacity 310 and the additional storage area free capacity 312 (step S521).

  If the data size (N + 1) is larger than the sum of the contract area free space 310 and the additional storage area free space 312 in step S521, the file (N + 1) is registered even if the additional storage area 23 is allocated. Since this means that sufficient free capacity cannot be obtained and an overflow state occurs, the process proceeds to error processing in step S541. Otherwise, the process proceeds to step S522.

  When the process proceeds to step S522, the additional storage area 23 is newly allocated to register the file (N + 1). First, the current time is acquired from the internal clock 215 (step S522), the value of the capacity excess flag 313 is changed to Yes (step S523), and the excess occurrence date and time 316 is updated to the time acquired in step S522 (step S524). The value of the contract area free space 310 is updated to 0 (step S525).

  Then, the additional storage area 23 is acquired from the low performance data storage unit 15 (step S526), the additional storage area disk ID 311 of the acquired additional storage area 23 is registered (step S527), and the file (N + 1) is registered. The free capacity of the additional storage area 23 is calculated and registered in the additional storage area free capacity 312 (step S528), and the update date and time 317 is updated to the time acquired in step S522 (step S529). In step S551, the data registration process shown in FIG. 10 is executed.

  If the process proceeds to step S531 in the determination of step S503, it means that the additional storage area 23 has already been allocated. The contract area free space 310 is zero. In this case, it is determined whether or not the data size (N + 1) is larger than the additional storage area free space 312 (step S531). If the data size (N + 1) is larger than the additional storage area free space 312, it means that sufficient free space for registering the file (N + 1) is not obtained and an overflow state occurs. move on. Otherwise, the process proceeds to step S532.

  When the process proceeds to step S532, first the current time is acquired from the internal clock 215 (step S532), and the value of the accumulated excess time 315 is updated to “the time obtained by subtracting the excess occurrence date and time 316 from the time acquired in step S532”. (Step S533). Then, the free capacity of the additional storage area 23 when the file (N + 1) is registered is calculated to update the additional storage area free capacity 312 (step S534), and the update date and time 317 is updated to the time acquired in step S532 (step S535). ). In step S551, the data registration process shown in FIG. 10 is executed.

  If the process proceeds to step S541 as determined in step S521 or 531, an overflow condition has occurred and the file (N + 1) cannot be registered, so an error message is returned to the client device 21 that is the data registration request source (step S541), the process ends.

  If the process proceeds to step S551, it means that the file (N + 1) can be registered. Therefore, the data registration process shown in FIG. 10 is executed to register the file (N + 1) (step S551). Exit.

  FIG. 13 is a flowchart showing processing performed by the program 231 for the billing information 300 during the data deletion processing shown in FIG. First, after confirming the data size (M) that is the capacity of the file (M) to be deleted (step S601), the excess capacity flag 313, the contract area free capacity 310, the additional storage area free capacity recorded in the billing information 300 are checked. 312 and the extended area maximum capacity 305 are confirmed (step S602). Thereafter, the data deletion process shown in FIG. 11 is executed to delete the file (M) (step S603).

  Then, it is determined whether or not the capacity excess flag 313 is Yes (step S604). If the excess capacity flag 313 is Yes, the additional storage area 23 is currently allocated, and the process proceeds to step S605 described later. If the excess capacity flag 313 is No, the additional storage area 23 is not currently allocated, and the process advances to step S611.

  If the additional storage area 23 is currently allocated, the combined capacity of the data size (M) confirmed in step S601 and the additional storage area free capacity 312 confirmed in step S602 is the expansion area maximum capacity 305. It is determined whether it is larger (step S605). If the combined capacity of the data size (M) and the additional storage area free capacity 312 is larger than the expansion area maximum capacity 305, it is not necessary to use the additional storage area 23, and the process proceeds to step S621. If the combined capacity is within the expansion area maximum capacity 305, the additional storage area 23 is continuously used, and the process proceeds to step S631.

  If the process proceeds to step S611 in the determination of step S604, it means that the additional storage area 23 is not currently allocated. When the file (M) is deleted from this state, the contract area free space 310 is increased by the data size (M) from there, so there is no need to allocate the additional storage area 23. In this case, the current time is acquired from the internal clock 215 (step S611), the value of the contract area free space 310 is updated to a value obtained by adding the data size (M) from the current value (step S612), and the update date and time 317. Is updated to the time acquired in step S611 (step S613), and the process ends.

  If the process proceeds to step S621 as a result of the determination in steps S604 to 605, it means that the additional storage area 23 has been allocated but it is no longer necessary to use the additional storage area 23 by deleting the file (M). To do. In this case, the current time is first acquired from the internal clock 215 (step S621), the value of the capacity excess flag 313 is changed to No (step S622), the excess occurrence date and time 316 is deleted (step S623), and the contract area is empty. The value of the capacity 310 is updated to “a value obtained by subtracting the expansion area maximum capacity 305 from the total capacity of the data size (M) and the additional storage area free capacity 312” (step S624).

  Then, the value of the cumulative excess time 315 is updated to “time obtained by subtracting the excess occurrence date and time 316 from the time acquired in step S621” (step S625), the additional storage area disk ID 311 is deleted (step S626), and the additional storage area is empty. The capacity 312 is deleted (step S627), the update date and time 317 is updated to the time acquired in step S621 (step S628), the additional storage area 23 is returned to the low performance data storage unit 15 (step S629), and the process is performed. finish.

  If the process proceeds to step S631 as determined in steps S604 to 605, it means that the additional storage area 23 is currently allocated and it is necessary to continue using the additional storage area 23 after the file (M) is deleted. To do. In this case, first, the current time is acquired from the internal clock 215 (step S631), and the value of the accumulated excess time 315 is updated to “the time obtained by subtracting the excess occurrence date and time 316 from the time acquired in step S631” (step S632). . Subsequently, the additional storage area free space 312 is updated to a value obtained by subtracting the data size (M) from the current value (step S633), and the update date and time 317 is updated to the time acquired in step S631 (step S634). The process ends.

  14 to 15 are flowcharts showing processing performed by the program 231 on the billing information 300 during the data update processing shown in FIGS. First, after confirming the data size (M) which is the capacity of the file (M) to be deleted and the data size (N) which is the capacity of the file (N) to be added (step S701), the capacity excess flag 313, the contract The area free capacity 310, the additional storage area free capacity 312 and the extended area maximum capacity 305 are confirmed (step S702). Thereafter, the data deletion process shown in FIG. 11 is executed to delete the file (M) (step S703).

  Then, it is determined whether or not the capacity excess flag 313 is Yes (step S704). If the excess capacity flag 313 is Yes, the additional storage area 23 is currently allocated, and the process proceeds to step S705 described later. If the excess capacity flag 313 is No, the additional storage area 23 is not currently allocated, and the process proceeds to step S706.

  If the process proceeds to step S705 as determined in step S704, it means that the additional storage area 23 is currently allocated. In this case, (data size (M) −data size (N)) + additional storage area free space 312, that is, the file (M) is replaced with the file (N) from each data size confirmed in step S 701. It is determined whether the total capacity of the data to be added and the additional storage area free capacity 312 is larger than the expansion area maximum capacity 305 (step S705).

  If the total capacity of the decreasing data capacity and the additional storage area free capacity 312 is larger than the expansion area maximum capacity 305, it is no longer necessary to use the additional storage area 23, and the process proceeds to step S721. If the combined capacity is within the expansion area maximum capacity 305, the additional storage area 23 is continuously used, and the process proceeds to step S711.

  If the process proceeds to step S706 in the determination in step S704, it means that the additional storage area 23 is not currently allocated. In this case, the data size (N) −data size (M) from each data size confirmed in step S701, that is, the capacity of the data that is increased by replacing the file (M) with the file (N) is the contract area free capacity. It is determined whether it is larger than 310 (step S706).

  If the increasing data capacity is larger than the contract area free capacity 310, it is necessary to newly allocate the additional storage area 23, so the process proceeds to step S741. If the capacity of the data to be increased is within the contract area free capacity 310, it is not necessary to allocate the additional storage area 23, so the process proceeds to step S731.

  When the file (M) is replaced with the file (N), the total data capacity after the replacement exceeds the total capacity of the user area 100 including the contract area 22 and the additional storage area 23. Since an overflow condition occurs, the replacement process is terminated and an error message is returned to the client device 21 (similar to steps S521, 531 and 541 in FIG. 12). In FIG. 14, the description of this processing is omitted in order to avoid complication of the drawing.

  When the process proceeds to step S711 as determined in steps S704 to 705, the additional storage area 23 is currently allocated, and it is necessary to continue using the additional storage area 23 after replacing the file (M) with the file (N). It means that there is.

  In this case, first, the current time is acquired from the internal clock 215 (step S711), and the value of the accumulated excess time 315 is updated to “the time obtained by subtracting the excess occurrence date and time 316 from the time acquired in step S711” (step S712). . Subsequently, the additional storage area free space 312 is updated to a value obtained by subtracting the data size (M) from the current value and adding the data size (N) (step S713), and the update date and time 317 is obtained at the time acquired in step S711. Update (step S714) and proceed to step S751.

  When the process proceeds to step S721 based on the determination in steps S704 to 705, the additional storage area 23 has been allocated, but it is not necessary to use the additional storage area 23 by replacing the file (M) with the file (N). Means that

  In this case, the current time is first obtained from the internal clock 215 (step S721), the value of the capacity excess flag 313 is changed to No (step S722), the excess occurrence date and time 316 is deleted (step S723), and the contract area is empty. The value of the capacity 310 is updated to “a value obtained by subtracting the expansion area maximum capacity 305 from the total capacity of the data capacity reduced by replacing the file (M) with the file (N) and the additional storage area free capacity 312”. (Step S724).

  Then, the value of the cumulative excess time 315 is updated to “time obtained by subtracting the excess occurrence date and time 316 from the time acquired in step S721” (step S725), the additional storage area disk ID 311 is deleted (step S726), and the additional storage area is empty. The capacity 312 is deleted (step S727), the update date and time 317 is updated to the time acquired in step S621 (step S728), the additional storage area 23 is returned to the low performance data storage unit 15 (step S729), and step S751. Proceed to

  If the process proceeds to step S731 based on the determination in steps S704 and 706, the additional storage area 23 is not currently allocated, and it is not necessary to allocate the additional storage area 23 even after the file (M) is replaced with the file (N). Means that. In this case, the current time is acquired from the internal clock 215 (step S731), and the value of the contract area free space 310 is updated to a value obtained by adding the data size (M) to the current value and subtracting the data size (N). (Step S732), the update date and time 317 is updated to the time acquired in Step S731 (Step S733), and the process proceeds to Step S751.

  If the determination in steps S704 and 706 has proceeded to step S741, the additional storage area 23 is not currently allocated, but the file (M) cannot be replaced with the file (N) only with the contract area free space 310. This means that the additional storage area 23 needs to be newly allocated. In this case, the current time is first acquired from the internal clock 215 (step S741), the value of the capacity excess flag 313 is changed to Yes (step S742), and the excess occurrence date and time 316 is updated to the time acquired in step S741 ( In step S743), the value of the contract area free space 310 is updated to 0 (step S744).

  Then, the additional storage area 23 is acquired from the low performance data storage unit 15 (step S745), the additional storage area disk ID 311 of the acquired additional storage area 23 is registered (step S746), and the file (M) is changed to the file (N). Is calculated and registered in the additional storage area free space 312 (step S747), the update date and time 317 is updated to the time acquired in step S741 (step S748), and step S751. Proceed to

  If the process proceeds to step S751, the data registration process shown in FIG. 10 is executed to register the file (N), and the process ends. Note that the specific processing performed when deleting, registering, and replacing a file is not necessarily limited to the examples shown in FIGS. For example, substantially the same determination is made by a method other than the example shown in FIGS. 10 to 15 by determining whether the capacity stored in the contract area 22 and the additional storage area 23 exceeds the contract capacity 304 or the like. You can also.

  FIG. 16 is a conceptual diagram showing an example of a user interface screen displayed on the client device 21 by the program 231 when the file storage device 10 shown in FIGS. 1 and 8 deletes or registers a file. FIG. 16A shows a file deletion instruction screen 800. The user can select a file to be deleted from the user area 100 by inputting a user ID 801 and a deletion target file name 802 and pressing a delete button 803. Note that a list of file names currently registered in the user area 100 may be displayed, and a deletion target file name 802 may be selected therefrom. If a cancel button 804 is pressed, the process can be interrupted.

  FIG. 16B shows a file deletion confirmation screen 810. When the delete button 803 is pressed on the file deletion instruction screen 800, the process proceeds to the file deletion confirmation screen 810, and the contents input by the user ID 801 and the deletion target file name 802 are displayed as a message 811. If the delete execution button 812 is pressed here, the file deletion processing shown in FIGS. 11 and 13 is executed for the file specified by the deletion target file name 802 of the user specified by the user ID 801. If a cancel button 813 is pressed, the process can be interrupted.

  FIG. 16C shows a file registration instruction screen 820. The user can select a file to be registered in the user area 100 by inputting a user ID 821, a registration source file name 822, a registration destination file name 823, and a comment 824 and pressing a registration button 825. A list of file names on the local disk may be displayed in the user area 100, and the registration source file name 822 may be selected therefrom. If a cancel button 826 is pressed, the process can be interrupted.

  FIG. 16D shows a file registration confirmation screen 830. When the registration button 825 is pressed on the file registration instruction screen 820, the screen proceeds to the file registration confirmation screen 830, and the contents entered in the user ID 821, registration source file name 822, registration destination file name 823, and comment 824 are displayed in a message 831. If the registration execution button 832 is pressed here, the file registration shown in FIGS. 10 and 12 is performed for the file specified by the registration source file name 822 and the registration destination file name 823 of the user specified by the user ID 801. Processing is executed. If the cancel button 833 is pressed, the processing can be interrupted.

  The file replacement input screen and the confirmation screen shown in FIGS. 14 to 15 are not shown here, but are registered with the file name to be deleted in a manner similar to the example shown in FIGS. 16 (a) to 16 (d). The user interface screen may be configured to select the file name.

  Of course, the content entered above is only an example. For example, a password may be input at the same time, thereby performing user authentication. In that case, the password may be stored in the management information storage unit 12. In addition, the contents such as the description of each file to be stored, which is input as the comment 824, may be stored in the billing information 300.

  FIG. 17 is a conceptual diagram showing an example of a user interface screen displayed on the client device 21 by the program 231 when the file storage device 10 shown in FIGS. 1 and 8 edits the contents registered in the billing information 300. It is. FIG. 17A shows a billing information setting / update screen 900. The user inputs information such as a user ID 901, contract capacity 902, expansion capacity 903, e-mail address 904, and comment 905. Other information registered in the billing information 300 can be displayed and edited.

  If a registration button 906 is pressed, a new user account is created with the input contents. If an update button 907 is pressed, the registered contents of the user corresponding to the existing user ID 901 are updated. If a cancel button 908 is pressed, the processing can be interrupted.

  FIG. 17B shows a file billing information setting / update confirmation screen 910. When the registration button 906 or the update button 907 is pressed on the billing information setting / update screen 900, the processing proceeds to the file billing information setting / update confirmation screen 910, where the user ID 901, contract capacity 902, expansion capacity 903, e-mail address 904, and comment 905 are used. The entered content is displayed as a message 911. If the setting / update execution button 912 is pressed here, the contents input on the charging information setting / updating screen 900 are reflected on the charging information 300. If a cancel button 913 is pressed, the processing can be interrupted.

  The information input here is reflected in the billing information 300. More specifically, the user ID 901 corresponds to the customer ID 301, the contract capacity 902 corresponds to the contract capacity 304, the expansion capacity 903 corresponds to the expansion area maximum capacity 305, and the mail address 904 corresponds to the contact mail address 307. Other information included in the billing information 300 may be input and edited on the billing information setting / update screen 900.

  As explained above, according to the present embodiment, data is temporarily stored exceeding the contract capacity by simply performing a normal file storage or update operation without explicitly changing the contract. Storage services that can be provided can be provided. At this time, if a grace time 306 when the contract capacity is exceeded is set, the user can use the additional storage area 23 free of charge within this grace time, and if this time is exceeded, the cumulative excess time 315 Based on the above, it is possible to charge an extended charge to the user. The user does not need to be particularly aware of exceeding the contract capacity for a short period of time, and of course, excessive charging is suppressed.

  For example, when the accumulated excess time 315 is updated as shown in step S533 of FIG. 12, step S632 of FIG. And when the accumulated excess time 315 exceeds the contract capacity excess grace time 306, the extended charging flag 314 may be set to Yes. If the extended billing flag 314 is Yes at the time of billing billing such as monthly, the user is billed for extension billing. When the billing billing processing is completed, the extended billing flag 314 is reset.

  Further, the additional storage area 23 is used only for a short time, and it is not necessary to ensure long-term reliability. In addition, it is used less frequently than the contract area 22. Therefore, the additional storage area 23 can be provided by the low performance data storage unit 15. Therefore, the number of expensive high performance disk devices 34 prepared by the service provider can be reduced, and the storage service can be provided with less equipment investment.

  Furthermore, since the capacity of the user area 100 in which the user can store data does not exceed the total capacity of the contract area 22 and the additional storage area 23, there is little risk of data being stored up to the entire capacity of the disk device. This also leads to a reduction in capital investment.

  Various conditions included in the billing information 300, such as contract capacity 304, extended area maximum capacity 305, contract capacity excess grace time 306, etc. are individually set for each user, so the contract conditions (billing arrangement) for each user are set. It becomes possible to set flexibly. For example, for users who frequently use the additional storage area 23 beyond the contract capacity excess grace time 306 (occurrence of extended billing), review the contract conditions such as expanding the contract capacity 304. Can do.

  Further, for example, when the time obtained by subtracting the accumulated excess time 315 from the contract capacity excess grace time 306 falls below a predetermined threshold (about several hours), the address registered in the contact e-mail address 307 is changed to “within several hours. A warning such as “Extended billing will occur” may be sent by e-mail. As a means for transmitting a warning, in addition to an electronic mail, a call to a voice telephone or a short message can be used.

[Second Embodiment]
FIG. 18 is a functional block diagram showing the configuration of the file storage apparatus 1000 according to the second embodiment of the present invention. The file storage device 1000 has the same components as the file storage device 10 according to the first embodiment of the present invention. The difference is that the storage information control unit 11 and the control program storage unit 13 are configured by a control device 1010 which is a single computer, and the management information storage unit 12, the high performance data storage unit 14, and the low performance data storage unit 15 are included. Are configured with separate storage devices.

  That is, the file storage device 1000 is different from the file storage device 10 according to the first embodiment of the present invention only in the physical division of the device, and the configuration and operation are completely the same. Therefore, description of the operation is omitted.

[Third Embodiment]
In the third embodiment of the present invention, the configuration and function of the apparatus are the same as those described as the first and second embodiments. The difference is that the user interface screen shown in FIG. 16 deletes or registers one file at a time. In this embodiment, a plurality of target files are designated at a time, and each of them is designated. In contrast, deletion or registration processing can be performed.

  FIG. 19 is a conceptual diagram showing an example of a user interface screen displayed on the client device 21 by the program 231 when deleting or registering a file in the file storage device according to the third embodiment of the present invention. The input screen allows you to enter multiple files to be deleted or registered, and the confirmation screen displays all the file names that have been entered multiple times. Since it is the same as that shown in FIG. 16, the same reference numerals are given to the same elements, and description thereof is omitted.

  Even when a plurality of files are designated as targets to be deleted or registered, the file deletion or file registration process shown in FIGS. 10 to 13 is only performed for each target file. No new action is added.

  Furthermore, the file deletion or registration operation may be performed more intuitively by applying a tree view type interface such as Windows (registered trademark) Explorer of Microsoft Corporation. In this case as well, only the user interface changes, and the file deletion and file registration operations performed by the file storage device are the same.

  The service to which the embodiment described above is applied is not limited to a so-called rental storage service. For example, even in a hosting service that provides a web server, an e-mail server, etc., the capacity of data stored in the contract area 22 may increase when these servers are operated. In that case, if the data exceeding the contracted capacity is not stored, there is a possibility that the service is stopped in the server. In such a case, the additional storage area 23 can be allocated to avoid service stoppage.

  Although the present invention has been described with the specific embodiments shown in the drawings, the present invention is not limited to the embodiments shown in the drawings, and is known so far as long as the effects of the present invention are achieved. It goes without saying that any configuration can be adopted.

  It can be used in an ASP that provides an area for storing a file to a user through a network.

It is a functional block diagram which shows the structure of the file storage apparatus which concerns on the 1st Embodiment of this invention. It is a conceptual diagram which shows the image which looked at the rental storage service provided by the file storage apparatus shown in FIG. 1 from the client apparatus. It is a conceptual diagram which shows the operation | movement in which the additional storage area is produced in the file storage apparatus shown in FIG. It is a conceptual diagram which shows operation | movement when the data which exceed contract capacity are memorize | stored in the file storage apparatus shown in FIG. It is a conceptual diagram which shows the operation | movement by which the additional storage area is open | released by deletion of unnecessary data in the file storage apparatus shown in FIG. It is a conceptual diagram which shows the operation | movement of a data update with the file storage apparatus shown in FIG. It is a conceptual diagram which shows the structure of the file management information in the file storage apparatus shown in FIG. It is a functional block diagram which shows the structure of the file storage apparatus shown in FIG. 1 in more detail. It is a conceptual diagram which shows the data structure of the accounting information shown in FIG. FIG. 9 is a flowchart illustrating processing performed by a program for file management information when a user requests data registration in a user area via a client device in the file storage device illustrated in FIGS. 1 and 8. 9 is a flowchart showing processing performed by a program for file management information when a user requests data deletion to a user area via a client device in the file storage device shown in FIGS. 1 and 8. It is a flowchart showing the process which a program performs with respect to charging information in the process of data registration shown in FIG. It is a flowchart showing the process which a program performs with respect to charging information in the process of data deletion shown in FIG. It is a flowchart showing the process which a program performs with respect to charging information in the process of the data update shown to FIGS. It is a continuation of FIG. FIG. 9 is a conceptual diagram illustrating an example of a user interface screen that a program displays on a client device when a file is deleted or registered in the file storage device illustrated in FIGS. 1 and 8. FIG. 9 is a conceptual diagram illustrating an example of a user interface screen that a program displays on a client device when editing contents registered in billing information in the file storage device illustrated in FIGS. 1 and 8. It is a functional block diagram which shows the structure of the file storage apparatus which concerns on the 2nd Embodiment of this invention. It is a conceptual diagram which shows the example of the user interface screen which a program displays on a client apparatus, when deleting or registering a file with the file storage apparatus which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 File storage apparatus 11 Accumulated information control part 12 Management information storage part 13 Control program storage part 14 High performance data storage part 15 Low performance data storage part 20 Network 21 Client apparatus 22 Contract area 23 Additional storage area 34 High performance disk apparatus 35 Low Performance disk device 41 First user data 42 Second user data 43 Third user data 44 Fourth user data 100 User area 101 File management information 111 Disk ID
112 Number of stored files 121 Identifier 122 Storage location start address 123 Data size 211 CPU
212 Communication Control Device 213 First Temporary Storage Memory 214 Second Temporary Storage Memory 215 Internal Clock 216 RAID Control Device 217 Virtual Storage Area Management Table 300 Billing Information

Claims (16)

A file storage device capable of saving and deleting files,
A first data storage unit in which a contract area in which one or a plurality of files can be saved and deleted within a predetermined contract capacity range is secured;
A second data storage unit provided separately from the first data storage unit;
A management information storage unit storing the contract capacity;
Accumulation information control for creating an additional storage area in the second data storage unit when the total capacity of one or more files stored in the contract area exceeds the contract capacity when a file is added to the contract area And a file storage device.   When the accumulated information control unit deletes one or more files stored in the contract area and the additional storage area, and the total capacity of the remaining files is less than the contract capacity, the addition The file storage device according to claim 1, wherein the storage area is released.   The accumulated information control unit calculates a time during which the additional storage area exists in the second data storage unit, and stores the time in the management information storage unit as a cumulative excess time, The file storage device according to claim 2.   The file storage device according to claim 3, wherein the management information storage unit stores a capacity excess grace time that is an upper limit value of the accumulated excess time.   5. The file storage device according to claim 4, wherein the storage information control unit issues a warning when a time obtained by subtracting the accumulated excess time from the capacity excess time delay falls below a predetermined threshold.   The file storage device according to claim 2, wherein the management information storage unit stores an extended area maximum capacity that is a maximum capacity of the additional storage area.   When the storage information control unit adds a file to the contract area, the total capacity of one or more files stored in the contract area and the additional storage area is the sum of the contract capacity and the maximum capacity of the extension area. The file storage device according to claim 6, wherein the process for adding the file is interrupted when the file is exceeded. A method of storing a file in a file storage device having a first data storage unit and a second data storage unit,
A contract area securing step for securing a contract area in which one or a plurality of files can be saved and deleted within a predetermined contract capacity range in the first data storage unit;
A contract capacity storing step of storing a contract capacity that is the maximum capacity of the contract area;
A first file capacity determination step of determining whether or not the total capacity of one or more files stored in the contract area exceeds the contract capacity when a file is added to the contract area;
A file storage method comprising: an additional storage area creation step of creating an additional storage area in the second data storage unit when the total capacity exceeds the contracted capacity in the first file capacity determination step; . Determining whether or not the total capacity of the remaining files is less than the contracted capacity when one or more files stored in the contracted area and the additional storage area are deleted; File capacity judgment process,
9. The file storage method according to claim 8, further comprising an additional storage area releasing step of releasing the additional storage area when the total capacity is less than the contracted capacity in the second file capacity determination step.   Calculating a time during which the additional storage area exists in the second data storage unit, and storing the time as a cumulative excess time in the management information storage unit; The file storage method according to claim 9.   11. The file archiving method according to claim 10, wherein the contract area securing step includes a capacity excess time delay storage step of storing a capacity excess time delay which is an upper limit value of the cumulative excess time.   12. The cumulative excess time calculating step includes a warning step of issuing a warning when a time obtained by subtracting the cumulative excess time from the capacity excess grace time falls below a predetermined threshold. File storage method.   The file storage method according to claim 9, wherein the contract area securing step includes an extended area maximum capacity storing step of storing an extended area maximum capacity that is a maximum capacity of the additional storage area. When a file is added to the contract area, it is determined whether the total capacity of the file or files stored in the contract area and the additional storage area exceeds the sum of the contract capacity and the maximum capacity of the extension area A third file capacity determination step,
An error processing step of interrupting the processing related to the addition of the file when the total capacity exceeds the total of the contracted capacity and the expansion area maximum capacity in the third file capacity determination step. The file storage method according to claim 13. A computer for controlling a file storage device having a first data storage unit and a second data storage unit;
A contract area securing process for securing a contract area capable of storing and deleting one or more files within a predetermined contract capacity range in the first data storage unit;
A contract capacity storage process for storing a contract capacity that is the maximum capacity of the contract area;
A first file capacity determination process for determining whether a total capacity of one or more files stored in the contract area exceeds the contract capacity when a file is added to the contract area;
File storage, wherein when the total capacity exceeds the contracted capacity in the first file capacity determination step, the second data storage unit executes an additional storage area creation process for creating an additional storage area program. Determining whether or not the total capacity of the remaining files is less than the contracted capacity when one or more files stored in the contracted area and the additional storage area are deleted; File capacity determination process,
16. The file storage program according to claim 15, wherein when the total capacity is less than the contracted capacity in the second file capacity determination step, an additional storage area release process for releasing the additional storage area is executed. .

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