JP4857841B2 - Data storage device, data input / output system, data storage device control method, and data storage device control program - Google Patents

Description

  The present invention relates to a data storage device, a data input / output system, a data storage device control method, and a data storage device control program, and more particularly to a data storage device, a data input / output system, and data capable of storing data hierarchically The present invention relates to a storage device control method and a data storage device control program.

  In the field of conventional data storage devices, it has been proposed to make it easier for the user to select data by using a method of classifying data by using a data folder or a method of presenting recently stored data. ing.

  In addition, it has been proposed that recently accessed data is listed as a candidate when selecting a file in word processing software or the like.

  However, when the above-described conventional classification by the data folder is adopted, there is a problem in that it is not easy to store data. In addition, when a method of selecting presentation data in time is adopted, there is a problem that necessary data is often not presented appropriately.

  The present invention has been made to solve the above problems, and is a data storage device, a data input / output system, a data storage device control method, and a data storage device capable of appropriately presenting data desired by a user The purpose is to provide a control program.

In order to achieve the above object, according to one aspect of the present invention, a data storage device for storing data divided into at least a first storage hierarchy, a second storage hierarchy, and a third storage hierarchy is provided in the first storage hierarchy. Using the first condition which is a condition based on the storage means for storing data, the data stored in the first storage hierarchy, the period in which the data is held in the first storage hierarchy, and the number of accesses to the data The first storage means for moving to the second storage hierarchy or the third storage hierarchy, and storing the data in the second storage hierarchy, the data stored in the second storage hierarchy, the period of holding the data in the second storage hierarchy, and the data Using the second condition, which is a condition based on the number of accesses, to move to the third storage hierarchy, and to store the second storage means, and in response to the data acquisition request, the data stored in the first storage hierarchy The second And a presentation means for presenting a third condition is satisfied data among the data stored in the storage hierarchy.

Preferably, the third condition can be determined by the user.
Preferably, the third condition is a condition related to a device used by the user, a condition related to a record taken out by the device used by the user, or data input by the device used by the user. It is a related condition.

  Preferably, the presenting means presents data having the same attribute as the data having a track record taken out by the device used by the user.

Preferably, the presenting means presents a predetermined number of data and stores the predetermined number for each user.
Preferably, data in the second storage hierarchy and the third storage hierarchy not presented by the presenting means can be referred to by searching.

  Preferably, the data storage device stores the first condition and the second condition for each user or for each device that outputs data.

  Preferably, when the data stored in the third storage hierarchy is referred to, the data storage device moves the data to the first storage hierarchy or the second storage hierarchy.

Preferably, the data storage device determines the number of data to be presented in response to the data acquisition request, and is included in the first condition and the second condition so that the number of data to be presented is equal to or less than the determined number of data. Adjustment means is provided for adjusting the number of presented data by repeating a process of changing the number of times of accessing data by a predetermined amount .

  According to another aspect of the present invention, a data input / output system is connected to the data storage device according to any one of the above and the data storage device, and inputs data to the data storage device or stores data from the data storage device. And an output device.

According to still another aspect of the present invention, there is provided a data storage device control method for storing data divided into at least a first storage hierarchy, a second storage hierarchy, and a third storage hierarchy. Using the first condition, which is a condition based on the storage step of storing the data, the data stored in the first storage hierarchy, the period of holding the data in the first storage hierarchy, and the number of accesses to the data . The first storage step to be moved to the second storage hierarchy or the third storage hierarchy and stored therein, the data stored in the second storage hierarchy, the period in which the data is held in the second storage hierarchy, and the access to the data using the second condition is a condition based upon the number is moved to the third storage hierarchy, where a second moving step to be stored, the data in response to a data acquisition request stored in the first storage hierarchy , And a third condition is satisfied data among the data stored in the second storage hierarchy, and a presenting step of presenting.

According to still another aspect of the present invention, at least a control program for a data storage device for storing data divided into a first storage hierarchy, a second storage hierarchy, and a third storage hierarchy is stored in the first storage hierarchy. Using the first condition, which is a condition based on the storage step of storing the data, the data stored in the first storage hierarchy, the period of holding the data in the first storage hierarchy, and the number of accesses to the data . The first storage step to be moved to the second storage hierarchy or the third storage hierarchy and stored therein, the data stored in the second storage hierarchy, the period in which the data is held in the second storage hierarchy, and the access to the data using the second condition is a condition based upon the number is moved to the third storage hierarchy, where a second moving step to be stored, in response to a data acquisition request stored in the first storage hierarchy And over data, to execute a third condition is satisfied data among the data stored in the second storage hierarchy, and a presentation step of presenting to the computer.

  According to these inventions, since data can be efficiently stored in the first to third layers, a data storage device, a data input / output system, and data that can appropriately present data desired by the user A storage device control method and a data storage device control program can be provided.

    [First embodiment]

  FIG. 1 is a diagram showing a configuration of a data storage system according to the first embodiment of the present invention.

  As shown in the figure, data input / output devices 300A and 300B, a data storage device 100, and a database 200 are connected on a network.

  The data storage device 100 and the database 200 implement three-level data storage. The data storage device 100 stores data in the first hierarchy (storage hierarchy 1) and the second hierarchy (storage hierarchy 2), and the database 200 stores data in the third hierarchy (storage hierarchy 3).

FIG. 2 is a diagram for explaining the concept of the data storage system of FIG.
As shown in the figure, a data storage request, an acquisition request, or a search request from a user using the data input / output devices 300A and 300B is input to the data storage device 100 or the database 200, thereby storing and acquiring the data. Or a search is performed.

  The storage hierarchy 1 constitutes a short-term storage hierarchy and stores newly input data. The storage hierarchy 3 constitutes a latent storage hierarchy and stores data that is not often used. The storage hierarchy 2 is located between the storage hierarchies 1 and 2 and constitutes an intermediate long-term storage hierarchy. For example, the latest data input within 2 to 3 days is placed in the short-term storage hierarchy, data continuously used for other data is placed in the long-term storage hierarchy, and data that is rarely used is placed in the latent storage hierarchy. The input data is first stored in the short-term storage hierarchy and moved to the long-term storage hierarchy or the latent storage hierarchy under a predetermined condition.

  When there is a request for data presentation from the user, the data in the short-term storage hierarchy and the data selected from the data in the long-term storage hierarchy are presented as the initial presentation. Thereby, it is possible to appropriately present data requested by the user.

  FIG. 3 is a block diagram illustrating a hardware configuration of the data input / output devices 300A and 300B, the data storage device 100, or the database 200 of FIG.

  Referring to the figure, one apparatus includes a CPU 601 for controlling the entire apparatus, a display 605, and a LAN (local area network) card 607 (or a modem card) for connecting to a network or communicating with the outside. An input device 609 including a keyboard and a mouse, a flexible disk drive 611, a CD-ROM drive 613, a hard disk drive 615, a RAM 617, and a ROM 619.

  Data such as programs and images recorded on the flexible disk F can be read by the flexible disk drive 611, and data such as programs and images recorded on the CD-ROM 613a can be read by the CD-ROM drive 613. Is possible.

FIG. 4 is a block diagram showing a functional configuration of the data storage device 100.
Referring to the figure, data storage device 100 includes a data input processing unit 101 for performing data input processing, a data output processing unit 103 for performing data output processing, and data for performing data search processing. Search processing unit 105, RAM 107 constituting storage hierarchy 1, data movement processing part (A) 109 for performing data migration processing from storage hierarchy 1 to 2 or 3, and hard disk drive (HDD) constituting storage hierarchy 2 ) 111, a data movement processing unit (B) 113 that performs data movement processing from the storage hierarchy 2 to 3, and a database control unit 115 that controls the database 200.

  The data movement processing unit (A) 109 refers to the data in the RAM 107 based on the data movement condition (A) 109a, acquires the data, stores the data in the HDD 111, or stores the data in the database 200. Is processed to output to the database control unit 115.

  The data movement processing unit (B) 113 refers to the data in the HDD 111 based on the data movement condition (B) 113a, acquires the data, and sends a request for storing the data in the database 200 to the database control unit 115. Output.

  In the data storage system according to the present embodiment, it is assumed that “confirmation interval A = 3 days” and “threshold A = 10 times of access” are recorded as data movement condition (A), and data movement condition (B) Assuming that “confirmation interval B = 10 days” and “threshold B = number of times of access” are recorded. It is assumed that data movement processing is performed at 0:00 every day.

  In each of the data stored in the storage tiers 1 and 2, the number of accesses to the data and the number of days that the data is retained are recorded.

FIG. 5 is a flowchart showing processing performed by the data movement processing unit (A) 109.
Referring to the figure, it is determined in step S101 whether or not a predetermined time (here, 0:00 every day) has been reached, and if YES, in step S103, data in storage hierarchy 1 that has reached confirmation interval A (predetermined retention period) Is moved to storage hierarchy 2 or 3 based on condition A (threshold A). That is, if the access count is greater than or equal to the threshold A, the access is moved to the storage hierarchy 2, and the others are moved to the storage hierarchy 3.

  In step S105, the number of accesses and the number of retention days stored in association with the data that has been moved are initialized. In step S107, the storage days of other data in the storage hierarchy 1 are incremented by 1, and the process returns to step S101.

FIG. 6 is a flowchart showing processing performed by the data movement processing unit (B) 113.
Referring to the figure, it is determined whether or not a predetermined time (here, 0:00 every day) has been reached in step S201. If YES, the data in storage hierarchy 2 that has reached confirmation interval B in step S203 (predetermined storage period) Are moved to the storage hierarchy 3 based on the condition B (threshold B). That is, those having the number of accesses equal to or higher than the threshold B are left in the storage hierarchy 2, and the others are moved to the storage hierarchy 3.

  In step S205, the number of accesses and the number of retention days stored in association with the data that has reached the confirmation interval B and has been processed are initialized. In step S207, the storage days of other data in the storage hierarchy 2 are incremented by 1, and the process returns to step S201.

FIG. 7 is a diagram illustrating a specific situation of data storage in the storage hierarchies 1 to 3.
Here, it is assumed that four data of DATA 17 to 20 are stored in the storage hierarchy 1, eight data of DATA 9 to 16 are stored in the storage hierarchy 2, and eight data of DATA 1 to 8 are stored in the storage hierarchy 3. Here, the numerical value after “DATA” indicates the ID of the data.

  In storage tiers 1 and 2, the ID of the data input / output device that is the input source of each data, the number of accesses and the number of retention days of each data are recorded. The IDs of the input data input / output devices are indicated by (A) and (B). (A) indicates that the data is input from the data input / output device 300A, and (B) indicates the data input. This indicates that the data is input from the output device 300B. The number of accesses is described numerically after “a”, and the number of retention days is described numerically after “h”.

  In the state of FIG. 7, when there is a data acquisition request from the data input / output device 300 </ b> A, the data output processing unit 103 displays all the data in the storage hierarchy 1 (data in the RAM 107) and the data in the storage hierarchy 2 (HDD 111). Data of the input device ID = A is output to the data input / output device 300A. Thereby, in FIG. 7, the data surrounded by the dotted line is output (presented).

  At 0 o'clock, the data movement processing unit (A) 109 and the data movement processing unit (B) 113 operate. The data movement processing unit (A) 109 performs a movement process on the DATAs 18 and 20 that are the data (h = 3) that have reached the confirmation interval A (= 3 days) among the data in the RAM 107. .

  Of the DATAs 18 and 20, the data whose access count a has reached the threshold A (= 10 access counts) is moved to the HDD 111, and the data that has not reached the threshold is moved to the database 200. At that time, the number of accesses a and the number of holding days h of the DATAs 18 and 20 to be processed are initialized.

  The data movement processing unit (B) 113 receives data 11, 12, 14, and 16 that are data (h = 10) that have reached the confirmation interval B (= 10 days) among the data in the HDD 111. To move.

  Among the DATAs 11, 12, 14, and 16, the data whose access count a has reached the threshold B (= access count 1) is left in the HDD 111, and the data that has not reached the threshold is moved to the database 200. At this time, the number of accesses a and the number of retention days h of the DATA 11, 12, 14, and 16 to be processed are initialized.

  As for the data stored in the database 200, only the ID of the input device is recorded, and the access count and the retention days are not recorded.

FIG. 8 is a diagram showing a result of performing the movement process from the state of FIG.
Data surrounded by a dotted line is moved (or held) as indicated by a solid line. That is, among the DATAs 18 and 20 that have reached the confirmation interval of the storage hierarchy 1, the DATA 20 that has reached the number of accesses 10 moves to the storage hierarchy 2 and the DATA 18 that has not reached the storage hierarchy 3 moves to the storage hierarchy 3. Of DATA 11, 12, 14, and 16 that have reached the confirmation interval of storage hierarchy 2, DATA 11, 12, 14 that has reached the number of accesses is held in storage hierarchy 2, and DATA 16 that has not reached is stored in storage hierarchy 3. Move to.

Further, for other data, the data retention days h are incremented by one.
FIG. 9 is a diagram showing a state in which three new data are input from the state of FIG.

  It is assumed that DATA21 is input from the data input device 300A and DATA22 and 23 are input from the data input device 300B. Those data are stored in the storage hierarchy 1 and become the state of FIG. If there is a data acquisition request from the data input device 300A in this state, DATA 17, 19, 21, 22, 23, 9, 10, 11, and 12 are presented.

  According to the present embodiment, new data (data in the storage hierarchy 1) stored in the data storage device 100 and data that is regularly used (stored) even if the user does not give any specific instruction. Data of the hierarchy 2) can be presented to the user. Thereby, a user's labor can be reduced. The user can obtain desired data by selecting one to be used from the presented data.

[Second Embodiment]
Since the configuration of the data storage system in the second embodiment is the same as that in the first embodiment, description thereof will not be repeated here. The present embodiment is characterized in that the data movement conditions A and B are automatically adjusted.

  In the state of FIG. 9, when there is a data acquisition request from the data input / output device 300A, the number of data to be acquired becomes 9 (DATA 17, 19, 21, 22, 23, 9, 10, 11, and 12). . If the user has set the maximum number of data acquisitions from the data input / output device 300A to 8 (maximum acquisition number), the number of data to be acquired will exceed. In the present embodiment, it is possible to prevent such an over from occurring.

  In the present embodiment, when over is detected in the state shown in FIG. 9 or the like, the movement process is virtually not performed at 0:00 just before.

FIG. 10 is a diagram illustrating a state where the movement process is not performed.
Here, DATA 16, 18, and 20 moved in FIG. 8 are returned to their original positions. In this state, while increasing the threshold A and the threshold B by one, the moving process is repeatedly tried until the number of data to be acquired from the data input / output device 300A becomes eight or less.

  In this case, when the thresholds become A = 12 (= 10 + 2) and B = 3 (= 1 + 2), the number of data to be acquired from the data input / output device 300A is eight.

  FIG. 11 is a diagram showing data movement processing at the time when the thresholds become A = 12, B = 3.

  In this state, the DATA 11 is moved to the storage hierarchy 3 by changing the threshold. The data movement condition is changed to these values (A = 12, B = 3), and the data arrangement is changed to the state after the data movement. The next 0:00 movement process is performed under the changed movement condition.

  If the [number of acquisition targets at each data input / output device] + [number of data registrations of the previous day] = [scheduled acquisition target number for the current day] is less than the maximum number of acquisitions after 0:00 move processing, The trial of movement is repeated while subtracting the thresholds A and B until immediately before the planned acquisition target number exceeds the maximum acquisition number. This makes it possible to acquire data of the number of data desired by the user.

  12 and 13 are flowcharts showing operations performed by the data storage device according to the second embodiment.

  Referring to the figure, when data movement is performed in step S301 as in the first embodiment, it is determined in step S303 whether the number of data acquisition targets exceeds the setting. If YES, it returns to the state where there was no movement in step S305, and the threshold is incremented by 1 in step S307.

  In step S309, it is determined whether the number of data acquisition targets at the time of movement exceeds the setting. If YES, the process returns to step S307.

  If “NO” in the step S309, the data moving condition is updated with the threshold at that time in a step S311, and the data is actually moved in a step S313.

  If NO in step S303, it is determined in step S315 in FIG. 13 whether the number of data acquisition targets is less than the set number. If YES, it returns to the state where there was no movement in step S317, and the threshold is decremented by 1 in step S319.

  In step S321, it is determined whether the number of data acquisition targets at the time of movement is immediately before the set maximum value is exceeded. If NO, it is determined in step S327 whether the threshold has become the minimum value (1 or the like), and if NO, the process returns to step S319.

  If “YES” in the step S321 or “YES” in the step S327, the data moving condition is updated with a threshold at that time in a step S323, and the data is actually moved in a step S325.

  Note that the maximum number of data acquisitions may be set for each data input / output device. For example, when the personal computer is a data input / output device, the maximum number of acquisitions is set to be large, and when an MFP (Multi Function Peripheral), a PDA (Personal Digital Assistant), and a mobile phone are data input / output devices. In consideration of the small display space, the maximum number of acquisitions is reduced. This maximum number of acquisitions may be user-configurable so that it can be adapted to user preferences.

[Modification]
In addition, regarding the data of the storage hierarchy 2, the data input by the data input / output device that issued the acquisition request is selected and output. However, instead of this, the selection may be performed under conditions determined by the user. .

  In addition, data having a track record that has been taken out by the data input / output device used by the user may be selected and output, or data having the same attribute as that of the track record that has been taken out may be selected and output. It may be.

  Further, the data movement conditions A and B may be held for each user or for each data input / output device.

  Furthermore, it is desirable that the user can refer to the data stored in the storage hierarchy 3 and the data stored in the storage hierarchy 2 that are not presented by a search operation or the like. At this time, if the data stored in the storage hierarchy 3 is referred to, the data may be moved to the storage hierarchy 1 or 2.

[Effects of the embodiment]
As described above, according to this embodiment, not only temporally new data stored in the storage hierarchy 1 but also data stored in the storage hierarchy 2 that is used continuously for a long time and meets the user's operation conditions. Is listed as a search candidate. Thereby, in the system which can input and output data with various devices, when presenting stored data to the user, there is an effect that the data required by the user can be appropriately presented.

  In the method of presenting a list of a predetermined number of data as candidates from the youngest access date of HDDs, which has been adopted in conventional storage devices, it has two layers of HDD and Backup, and has been registered relatively recently Data that is both inaccessible and non-accessed also rises to the top of the candidate. For this reason, data that has not been accessed recently but is used regularly is often out of the list. For example, in a list of the number limit 20 of users who newly create 20 or more data per week, the weekly report form used every week is out of the list.

  In the method according to the present embodiment, for data registered relatively recently in the storage hierarchy 1, data with a low access frequency is dropped into the storage hierarchy 3, and data with a high access frequency is left in the storage hierarchy 2. As a result, it is possible to treat both data that has been registered relatively recently and data that is used regularly as equivalent, and the data that is used periodically can be listed in a list with a limited number (for example, as described above). In this example, if 10 data are created but not accessed, they are dropped into the storage hierarchy 3, so the weekly report form will not be off the list).

  If the data in the storage hierarchy 2 is not used, it falls into the storage hierarchy 3 and can be omitted from the list candidates (for example, in the above example, the old weekly report form that is no longer used is dropped into the storage hierarchy 3).

  Further, by displaying the selected data in the data of the storage hierarchy 2 and the latest data of the storage hierarchy 1 as a list, it is possible to appropriately present the data desired by the user in the list with a limited number of items. There is.

  Further, according to the second embodiment, it is possible to appropriately present the number of data corresponding to the device with diversified data input / output devices.

  Also, if the apparatus is configured so that the user sets the number of data to be displayed as a list (maximum acquisition number) instead of the user setting the data movement condition between the storage tiers, the user setting becomes easy. .

  Also, by holding the data movement conditions A and B for each user and for each device, there is an effect that it is possible to cope with individual differences in the number of lists that can be listed and differences in capabilities of devices that perform display.

[Others]
A program for executing the processing of the flowchart in the above-described embodiment can be provided, or the program can be recorded on a recording medium such as a CD-ROM, a flexible disk, a hard disk, a ROM, a RAM, or a memory card. You may decide to provide it. The program may be downloaded to the apparatus via a communication line such as the Internet.

  Further, the present invention can be applied to a system connected to a network and a system not connected to a network environment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the structure of the data storage system in the 1st Embodiment of this invention. It is a figure for demonstrating the concept of the data storage system of FIG. 2 is a block diagram showing a hardware configuration of data input / output devices 300A and 300B, data storage device 100, or database 200 of FIG. 2 is a block diagram showing a functional configuration of a data storage device 100. FIG. It is a flowchart which shows the process which the data movement process part (A) 109 performs. It is a flowchart which shows the process which the data movement process part (B) 113 performs. It is a figure which shows the specific condition of the data storage in the storage hierarchy 1-3. It is a figure which shows the result of having performed the movement process from the state of FIG. FIG. 9 is a diagram illustrating a state in which three new data are input from the state of FIG. 8. It is a figure which shows the state which did not perform a movement process. It is a figure which shows the data movement process in the time of a threshold becoming A = 12 and B = 3. It is a flowchart which shows the operation | movement which the data storage device in 2nd Embodiment performs. It is a flowchart following FIG.

Explanation of symbols

  100 data storage device, 101 data input processing unit, 103 data output processing unit, 105 data search processing unit, 107 RAM (storage layer 1), 109 data movement processing unit, 109a data movement condition, 111 HDD (storage layer 2), 113 data movement processing unit, 113a data movement condition, 115 database control unit, 200 database (storage hierarchy 3), 300A, 300B data input / output device.

Claims (12)

A data storage device for storing data divided into at least a first storage hierarchy, a second storage hierarchy, and a third storage hierarchy,
Storage means for storing data in the first storage hierarchy;
The data stored in the first storage tier is stored in the second storage tier by using a first condition that is a condition based on a period in which the data is stored in the first storage tier and the number of accesses to the data. Moving to the third storage hierarchy and storing the first storage means there;
The data stored in the second storage tier is stored in the third storage tier using a second condition that is a condition based on a period in which the data is stored in the second storage tier and the number of accesses to the data. Second moving means for moving and storing there ;
In response to a data acquisition request, a presentation unit is provided for presenting data stored in the first storage hierarchy and data satisfying a third condition among the data stored in the second storage hierarchy . Data storage device.   The data storage device according to claim 1, wherein the third condition can be determined by a user. The third condition is related to a condition related to a device used by the user, a condition related to a record taken out by the device used by the user, or data input by the device used by the user. it is a condition for the data storage device according to claim 1 or 2. The data storage device according to any one of claims 1 to 3 , wherein the presenting unit presents data having the same attribute as data having a track record taken out by a device used by a user. The presentation unit presents a predetermined number of data, storing said predetermined number for each user, the data storage device according to claim 1. The data storage device according to any one of claims 1 to 5 , wherein data of the second storage hierarchy and the third storage hierarchy not presented by the presenting means can be referred to by a search. Storing said first and second conditions each user, or data for each device that outputs the data storage device according to any one of claims 1-6. If the data stored in the third storage hierarchy is referenced, the moving data into the first storage hierarchy or the second memory hierarchy, the data storage device according to any one of claims 1-7. The number of data to be presented in response to the data acquisition request is determined, and the number of accesses to the data included in the first condition and the second condition so that the number of data to be presented is equal to or less than the determined number of data. the respectively by repeating the process for a predetermined amount changes, with adjustable means for adjusting the number of data to be presented, the data storage device according to any one of claims 1-8. A data storage device according to any one of claims 1 to 9 ,
A data input / output system, comprising: a device connected to the data storage device for inputting data to the data storage device or outputting data from the data storage device. A method of controlling a data storage device for storing data divided into at least a first storage hierarchy, a second storage hierarchy, and a third storage hierarchy,
A storage step of storing data in the first storage hierarchy;
The data stored in the first storage tier is stored in the second storage tier by using a first condition that is a condition based on a period in which the data is stored in the first storage tier and the number of accesses to the data. Moving to the third storage hierarchy and storing it there;
The data stored in the second storage tier is stored in the third storage tier using a second condition that is a condition based on a period in which the data is stored in the second storage tier and the number of accesses to the data. A second moving step to move and store there ;
A presentation step of presenting data stored in the first storage hierarchy and data satisfying a third condition among the data stored in the second storage hierarchy in response to a data acquisition request , Data storage device control method. A control program for a data storage device for storing data divided into at least a first storage hierarchy, a second storage hierarchy, and a third storage hierarchy,
A storage step of storing data in the first storage hierarchy;
The data stored in the first storage tier is stored in the second storage tier by using a first condition that is a condition based on a period in which the data is stored in the first storage tier and the number of accesses to the data. Moving to the third storage hierarchy and storing it there;
The data stored in the second storage tier is stored in the third storage tier using a second condition that is a condition based on a period in which the data is stored in the second storage tier and the number of accesses to the data. A second moving step to move and store there ;
In response to a data acquisition request, a presentation step for presenting data stored in the first storage hierarchy and data satisfying a third condition among the data stored in the second storage hierarchy to the computer A data storage device control program to be executed.

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