JP2001154894A - Hierarchy storage device and method for controlling the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quickly process the retrieval processing of file information regardless of the contents of requests for read or write. SOLUTION: A cache memory 16 having a management information preserving area 16A and an actual data area 16B and a large capacity storage device 17 for storing the actual file data are hierarchically connected to a main memory 13, and the main memory 13 is provided with hierarchy storage managing software 20 for operating hierarchical storage management. File managing information such as a file name, file information, and the kind of a file and a part of actual data are written in a management information preserving area 16A of the cache memory 16, and the actual data are written in an actual data area 16B. The file management information and a part of the actual data written in the management information preserving area 16A are held so as to be always accessed regardless of the order of the requests for the read or write of data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a computer in which, for example, a storage device which is high speed but has a small storage capacity and a storage device which is relatively slow but has a large storage capacity are hierarchically connected and frequently accessed. The present invention relates to a hierarchical storage device and a control method of a hierarchical storage device that enable high-speed access to data by selectively recording part of data in a high-speed storage device.

[0002]

2. Description of the Related Art In recent years, in an information processing system, a demand for a large-capacity storage device has been increased with an increase in data amount due to the spread of networks and an increase in image data. If the entire large-capacity storage device is constituted by a high-speed semiconductor memory or the like, there is a problem that it becomes very expensive.

[0003] Therefore, attention is paid to the locality of access, in which most of generally recorded data is hardly accessed, and only some frequently accessed data is stored in a high-speed storage device. Hierarchical storage devices have been put to practical use in which most of the data that is not accessed much is stored in a storage device that can realize a large capacity at a relatively low speed but at a low cost.

FIG. 8 shows a configuration example of a conventional hierarchical storage device. 8, reference numeral 1 denotes an electronic computer such as a personal computer, which includes, for example, a CPU 2, a main memory 3 operating at high speed, a hard disk 4 storing various data and software, and a controller 5 for controlling a large-capacity storage device. A cache memory 6 is provided in the controller 5. As the large-capacity storage device 7 controlled by the controller 5, for example, a device that switches between a plurality of media A and B using an autochanger is used. Also, the media A and B are
For example, a storage medium having a large capacity but operating at a relatively low speed, such as an MO (magneto-optical disk) or a DVD, is used. As described above, in the hierarchical storage device, the cache memory 6 and the mass storage device 7 are hierarchically connected to the main memory 3.

In the above configuration, when the CPU 2 accesses the main memory 3 and the target data is not written in the main memory 3, the CPU 2 further searches the cache memory 6. If the data is not stored, the target data is read from the mass storage device 7 to the cache memory 6 and used.

By using the cache memory 6 and the large-capacity storage device 7 in a hierarchical connection as described above, the access frequency to the cache memory 6 is normally higher than the access frequency to the large-capacity storage device 7. Therefore, even if the low-speed mass storage device 7 is used, data access can be performed at high speed.

[0007]

However, in the conventional hierarchical storage device, data is temporarily stored irrespective of the read / write request contents such as the file creation date, size, type (document, image data, etc.). You. Therefore, when a large amount of data such as image data is requested, the data stored in the cache memory 6 is rewritten with the data read from the large-capacity storage device 7, and the frequency of use of directory information, file information, and the like is reduced. Since high information is erased from the cache memory 6, there is a problem that the data reading speed in subsequent requests is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and manages frequently used information such as directory information and file information separately from actual data, and stores frequently used information in a cache memory. A hierarchical storage device and a method of controlling a hierarchical storage device that can access frequently used information at high speed regardless of the contents of a read or write request by storing the information in a separate area. Aim.

[0009]

A hierarchical storage device according to a first aspect of the present invention has a cache memory having an actual data area and a management information storage area, and is hierarchically connected to the cache memory to store actual file data. A large-capacity storage device, and management information of each file stored in the large-capacity storage device is read in advance and stored in the management information storage area of the cache memory, and the real data of the file is temporarily stored in the real data area. Storage means for storing.

As described above, the management information of the file stored in the large-capacity storage device is stored and managed in the management information storage area in the cache memory, so that the file can be read regardless of the data reading or writing request order. The management information can always be held in the management information storage area, and the file information can be searched at high speed.

According to a second aspect of the present invention, there is provided a hierarchical storage device including a cache memory having an actual data area and a management information storage area, and a large-capacity storage apparatus hierarchically connected to the cache memory and storing actual file data. The file information of each file stored in the mass storage device, the file type, and a part of the actual data are read in advance and saved in the management information storage area of the cache memory, and the actual data of the file is Storage means for temporarily storing data in an actual data area.

By storing a part of the actual data for each file in the management information storage area as described above, when searching for the contents of each file, the actual data area of the cache memory is searched. A search process can be performed only in the management information storage area without accessing the storage device or the large-capacity storage device.

A hierarchical storage device according to a third aspect of the present invention is capable of exchanging a cache memory having an actual data area and a management information storage area, and a plurality of storage media hierarchically connected to the cache memory and storing actual data. A large-capacity storage device provided in, the file management information of each file stored in each storage medium of the large-capacity storage device is read in advance and stored in the management information storage area of the cache memory,
Storage means for temporarily storing the actual data of the file in the actual data area.

By storing and managing the management information of the file stored in the large-capacity storage device in the management information storage area in the cache memory as described above, the large-capacity storage device can exchange a plurality of storage media. Even if the configuration is such that the management information of each storage medium is stored in the management information storage area of the cache memory, the file information can be searched at high speed.

According to a fourth aspect, in the hierarchical storage device according to the third aspect, when one file is divided and stored in a plurality of storage media of a mass storage device, the file in each storage medium is It is characterized in that the type and the area in which the data is stored are determined, and the data for the time required for the exchange of the storage medium is stored in the management information storage area of the cache memory together with the file management information.

As described above, when a large-capacity file such as moving image data is divided and stored in a plurality of storage media, image data corresponding to the exchange time of the storage media is stored in the management information storage area. By storing the image data, the image data can be read from the management information storage area when the storage medium is switched, and can be displayed.

A hierarchical storage device according to a fifth aspect of the present invention is a cache memory having a real data area and a management information storage area, and a storage apparatus hierarchically connected to the cache memory and having a real data area and a management information storage area. A large-capacity storage device that is hierarchically connected to the storage device and stores actual data; and a file in which file management information of each file stored in the large-capacity storage device is read in advance and a management information storage area of the cache memory. And a first storage unit for temporarily storing real data of the file in a real data area, and reading in advance the real data of each file stored in the mass storage device, And a second storage means for temporarily storing the actual data in a management information storage area of the storage device. That.

As described above, the file information having a relatively small storage capacity is stored in the management information storage area of the cache memory, and a part of the actual data requiring a relatively large capacity is stored in the management information storage area of the storage device. By doing so, the search process can be performed at a high speed even when there are a large number of files or when the cache memory capacity is insufficient by caching large data such as image data.

According to a sixth aspect of the present invention, there is provided a hierarchical storage device control method for controlling a hierarchical storage device including a cache memory and a large-capacity storage device, wherein file management information and actual data are separately stored in the cache memory, It is characterized in that management information for each file stored in the large-capacity storage device is always kept accessible in a cache memory.

By maintaining the file management information in the cache memory as described above, the file information can be searched at high speed regardless of the data read or write request order.

According to a seventh aspect of the present invention, in the hierarchical storage device control method according to the sixth aspect, the file information of each file stored in the mass storage device, the type of the file, It is characterized in that a part of the actual data is always kept accessible in the cache memory.

As described above, a part of the actual data is always held in the cache memory so as to be accessible, so that when the content of each file is searched, only the management information storage area is used. Processing can be performed, and high-speed search can be performed.

According to an eighth aspect of the present invention, there is provided a method for controlling a hierarchical storage device, comprising: a cache memory having a management information storage area; a storage device having a management information storage area; and a large-capacity storage device storing actual data. Connected, read in advance the management information of each file stored in the mass storage device, save it in the management information storage area of the cache memory, and store the actual data of each file stored in the mass storage device. Is read in advance and stored in a management information storage area of the storage device.

As described above, a storage device for hierarchical storage is provided between the cache memory and the large-capacity storage device, and the file management information and a part of the actual data are stored separately in the cache memory and the storage device. Even when there are a large number of files, or when large data such as image data is cached and the capacity of the cache memory becomes insufficient, the search process can be performed at high speed.

[0025]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a configuration diagram of a hierarchical storage device according to a first embodiment of the present invention. In FIG. 1, reference numeral 11 denotes an electronic computer such as a personal computer.
For example, it comprises a CPU 12, a main memory 13 operating at high speed, a hard disk 14 storing various data and software, and a controller 15 for controlling a large-capacity storage device. A cache memory 16 is provided in the controller 15. As the mass storage device 17 controlled by the controller 15, a plurality of media (storage media) A, B,.
Is used by switching between the two. In this case, the medium C is an offline medium removed from the autochanger. The media A, B, and C are:
For example, a relatively low-speed but large-capacity storage medium such as an MO (magneto-optical disk) or a DVD is used.

Then, as shown in FIG.
3 for the cache memory 16 and the mass storage device 1
7 are hierarchically connected. Hierarchical storage management software 20 for performing such hierarchical storage management is provided in the main memory 13.

FIG. 3 shows the volume configuration of the entire hierarchical storage. In each medium A, B,... Of the mass storage device 17, a file is stored in each directory. The data of the file stored in each of the media A, B,... Is read out to the cache memory 16 as hierarchical storage as needed.

In the main memory 13, a management information storage area 16A is provided.
The file management information is written to 6A, and the real data is written to another area, that is, the real data area 16B. As shown in FIG. 4, the management information storage area 16A is provided with an area for storing frequently used information such as file names 21, file information 22, file types 23, cache data 24, and the like. In the file name storage area 21, for example, file names such as file 1, file 2,... Are written, and in the file information storage area 22, for example, files such as creation date and size for each medium A, B,. Information is written. The file type storage area 23 stores file types such as documents, audio data, and image data. The cache data storage area 24 stores, for example, the first 400 characters of the file in the file. For the data, audio data and moving image data, data for the first 10 seconds is written.

The management information stored in the management information storage area 16A is managed by the hierarchical storage management software 20, and is rewritten according to the attachment / detachment of the medium to / from the mass storage device 17. That is, the hierarchical storage management software 20
Monitors the attachment / detachment of the media A, B,... Of the mass storage device 17, and when the media is replaced, deletes the management information of the removed media from the management information storage area 16A and newly attaches the media. The management information is read from the read medium to determine the type of the file, and a part of the actual data is stored in the management information storage area 16A together with the file information in accordance with the type of the file.

As described above, the cache memory 16
When a medium is mounted on the autochanger, which is the mass storage device 17, part of the file management information and actual data is read from the medium and stored in the management information storage area 16A.

In the above configuration, when the CPU 12 accesses the main memory 13, the CPU 12
If the target data has not been written to 3, the management information storage area 16A of the cache memory 16 is further accessed. For real data that is not stored in the management information storage area 16A of the cache memory 16, the real data area 16B is further accessed, and the data is read and processed, but the real data is stored in the real data area 16B. If not, target data is read from the media A and B of the mass storage device 17 and processed.

Normally, the frequency of data access is often based on file information. However, the management information such as file information in the media A and B is always stored in the management information storage area 16A irrespective of the read or write request order. Since the file information is stored, the file information can be accessed at a high speed. For example, when searching files stored on the media A and B of the large-capacity storage device 17 and created after a certain date, all the file information is stored in the management information storage area 16A of the cache memory 16. Therefore, it is not necessary to access the media A and B, and the media A and B can be searched at high speed.

In the cache data storage area 24 of the management information storage area 16A, the first data of each file, for example, data of 400 characters when the file is a document, and 10 seconds when the file is voice data, Since the data of each file is always stored, when searching for the contents of each file, the actual data area 16B of the cache memory 16 and the media A and B of the large-capacity storage device 17 are searched. The search process can be performed only in the management information storage area 16A without accessing. For example, when the file type is a document, a part of the actual data such as the cover can be searched at high speed, and when the file type is audio data, the intro part can be viewed at high speed.

(Second Embodiment) Next, a second embodiment of the present invention will be described. In the first embodiment, the hierarchical storage management software 20 monitors the attachment / detachment of the media A, B,... Of the mass storage device 17, and when the media is replaced, the management information of the removed media is stored in the management information storage area. In the second embodiment, the management information of the removed medium, for example, the medium C is not deleted from the management information storage area 16A but is stored as it is in the second embodiment. With the above configuration, the file information and the like of the media C that has gone offline can be managed by the hierarchical storage management software 20. In this case, the hierarchical storage management software 20 uses the information in the management information storage area 16A when accessing management information such as file information in the offline medium C, and informs the user that the file is offline media when accessing actual file data. Notice. This makes it possible to search for management information such as file information of more media than can be actually inserted into the mass storage device 17.

(Third Embodiment) Next, a third embodiment of the present invention will be described. In the third embodiment, for example, when one moving image data is stored in the mediums A and B of the large-capacity storage device 17 in the first half and the second half separately, it is stored in the management information storage area 16A of the cache memory 16. The management information of the media A and B is configured as shown in FIG. That is, the file name 1 for the moving image is stored in the file name storage area 21 of the management information storage area 16A, and file information such as the creation date and size of the media A and B is stored in the file information storage area 22. In the file type storage area 23, “movie data (first half)” for medium A and “movie data (second half)” for medium B are stored as file types. The cache data storage area 24 stores the image data for the first 10 seconds for the medium A and the image data for at least the medium exchange time for the medium B.

The storage of the file management information and the image data in the management information storage area 16A is performed by the hierarchical storage management software 20. That is, the hierarchical storage management software 20 determines the file type and the area where the data is stored for the media A and B, and stores the data for the time necessary for the exchange of the medium together with the file management information together with the management information storage area 16A. To save.

When the autochanger mechanism is employed as the large-capacity storage device 17, it takes about 10 seconds or more to exchange the media. Therefore, when the media A and B are accessed normally, the media being reproduced at the time of the media exchange is changed. The video is interrupted. In this third embodiment, the management information storage area 1
Image data corresponding to the medium exchange time is read from the medium B and stored in the cache data storage area 24 of 6A in advance. Therefore, when switching from the medium A to the medium B in the reproduction process of the moving image, the moving image data for the medium B can be read from the cache data storage area 24 of the management information storage area 16A and displayed on the screen, thereby preventing the image from being interrupted. Video can be played continuously.

In the cache data storage area 24 of the management information storage area 16A, the first 10 seconds of moving image data for the medium A are also stored.
When searching for the contents of the file, the search process can be performed only in the management information storage area 16A without accessing the media A and B of the mass storage device 17.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described. FIG. 6 is a configuration diagram of the hierarchical storage device according to the fourth embodiment. The hierarchical storage device according to the fourth embodiment differs from the hierarchical storage device according to the first embodiment shown in FIG. 1 in that a hard disk 18 constituting a hierarchical storage is connected to a controller 15 together with a cache memory 16 and a mass storage device 17. Since other configurations are the same as those of the first embodiment, the same portions are denoted by the same reference numerals as those of the first embodiment, and detailed description is omitted.

The hierarchical storage device according to the fourth embodiment comprises:
As shown in FIG. 7, hierarchical storage is constituted by the cache memory 16, the hard disk 18, and the large-capacity storage device 17, and actual data is stored in the large-capacity large-capacity storage device 17 at low speed. The hard disk 18
Has a slower processing speed than the cache memory 16 but has a large storage capacity.

The hard disk 18 has a management information storage area 18A similarly to the cache memory 16, and has an actual data area 18B in other areas. In this case, the management information storage area 16A of the cache memory 16 is provided with a file name storage area 21, a file information storage area 22, and a file type storage area 23 having relatively small storage capacity in the management information shown in FIG. The cache data storage area 24 requiring a relatively large capacity in the management information storage area 18A of the hard disk 18.
Is provided.

The management information storage area 16A of the cache memory 16 and the management information storage area 18A of the hard disk 18 are managed by the hierarchical storage management software 20.

By providing the hard disk 18 for hierarchical storage having a larger capacity than the cache memory 16 between the cache memory 16 and the large-capacity storage device 17 as described above, it is possible to store a large number of files or to store image data. Even when such large data is cached and the capacity of the cache memory 16 becomes insufficient, the hard disk 18 can be accessed at a higher speed than the large-capacity storage device 17, so that the search process is performed at a high speed. be able to. According to the fourth embodiment, a greater effect can be exerted particularly when the storage capacity of the mass storage device 17 is very large.

In each of the above embodiments, the case where each medium of the large-capacity storage device 17 is processed as an independent storage device has been described. However, in other cases, for example, when a plurality of media are treated as one storage device. , In the same manner.

[0046]

As described above in detail, according to the present invention, in a hierarchical storage device in which a cache memory and a large-capacity large-capacity storage device are hierarchically connected, a management information storage area is provided in the cache memory. Since management information such as file information is stored and managed for each medium of the large-capacity storage device in the management information storage area, management information such as file information in each medium can be read and managed in the management information storage area. Can always be maintained regardless of the order of write requests,
File information can be searched at high speed.

Since a part of the actual data for each file is stored in the management information storage area, when searching for the content of each file, the cache memory is used. The search process can be performed only in the management information storage area without accessing the actual data area or the large-capacity storage device.

Further, when one moving image data is separately stored in a plurality of media of the mass storage device,
Since the image data corresponding to the media exchange time is read in advance from the corresponding medium and stored in the management information storage area, the image data can be read from the management information storage area and displayed when the medium is switched. A continuous moving image can be reproduced while preventing interruption of the video.

Further, according to the present invention, a hierarchical storage is constituted by a cache memory, a hierarchical storage hard disk, and a large-capacity storage device, and a management information storage area is provided in the cache memory and the hard disk. File information with a small storage capacity, and a part of the actual data that requires a relatively large capacity is stored in the management information storage area of the hard disk. Even when large data is cached and the capacity of the cache memory becomes insufficient, the search process can be performed at high speed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a hierarchical storage device according to a first embodiment of the present invention.

FIG. 2 is an exemplary view showing a state in which the cache memory and the large-capacity storage device in the embodiment are hierarchically connected;

FIG. 3 is an exemplary view showing a volume configuration of the entire hierarchical storage according to the embodiment;

FIG. 4 is an exemplary view showing a storage configuration example of a management information storage area of the cache memory in the embodiment.

FIG. 5 is a diagram showing a storage configuration example of a management information storage area of a cache memory according to a third embodiment of the present invention.

FIG. 6 is a configuration diagram of a hierarchical storage device according to a fourth embodiment of the present invention.

FIG. 7 is an exemplary view showing a state in which a cache memory, a hierarchical storage hard disk, and a mass storage device are hierarchically connected in the embodiment;

FIG. 8 is a configuration diagram of a conventional hierarchical storage device.

[Explanation of symbols]

 Reference Signs List 11 computer 12 CPU 13 main memory 14 hard disk 15 controller 16 cache memory 16A management information storage area 16B actual data area 17 large-capacity storage device 18 hierarchical storage hard disk 18A management information storage area 18B actual data area 21 file name storage area 22 file Information storage area 23 File type storage area 24 Cache data storage area

Claims (10)

[Claims] 1. A cache memory having an actual data area and a management information storage area, a large-capacity storage device hierarchically connected to the cache memory and storing actual file data, and a storage device in the large-capacity storage device. Storage means for reading in advance the file management information of each file stored in the management information storage area of the cache memory, and temporarily storing the actual data of the file in the actual data area. Storage device. 2. A cache memory having an actual data area and a management information storage area, a large-capacity storage device hierarchically connected to the cache memory and storing actual file data, and a storage device in the large-capacity storage device. Storage means for reading in advance the file information of each file, the type of file, and a part of the actual data, saving it in the management information storage area of the cache memory, and temporarily storing the actual data of the file in the actual data area A hierarchical storage device comprising: 3. A cache memory having an actual data area and a management information storage area, a large-capacity storage device hierarchically connected to the cache memory and having a plurality of storage media interchangeably storing actual data, A storage for reading out file management information of each file stored in each storage medium of the mass storage device in advance, storing the file management information in a management information storage area of the cache memory, and temporarily storing real data of the file in a real data area. A hierarchical storage device comprising: 4. The hierarchical storage device according to claim 3, wherein the file management information stored in the management information storage area of the cache memory is rewritten in response to exchange of a medium. 5. The hierarchical storage device according to claim 3, wherein the file management information stored in the management information storage area of the cache memory is kept as it is even after the corresponding medium is removed. 6. The hierarchical storage device according to claim 3, wherein
When one file is divided and stored in a plurality of storage media of a large-capacity storage device, a file type and an area where data is stored in each storage medium are determined, and a time required for replacement of the storage media is determined. 4. The hierarchical storage device according to claim 3, wherein the data for each minute is stored in a management information storage area of a cache memory together with file management information. 7. A cache memory having a real data area and a management information storage area, a storage device hierarchically connected to the cache memory, and having a real data area and a management information storage area, and a storage device hierarchically connected to the storage device. A large-capacity storage device that stores actual data, and file management information of each file stored in the large-capacity storage device are read in advance and stored in a management information storage area of the cache memory, and the actual data of the file is stored. First storage means for temporarily storing the actual data in a real data area, real data of each file stored in the mass storage device is read in advance, and the real data is temporarily stored in the real data area of the storage device. And a second storage unit for storing a part of the storage device in a management information storage area of the storage device. 8. A method for controlling a hierarchical storage device comprising a cache memory and a large-capacity storage device, wherein the management information of the file and the actual data are separately stored in the cache memory. A method for controlling a hierarchical storage device, characterized in that management information for each file stored in the device is always kept accessible in a cache memory. 9. File information of each file stored in a mass storage device as the file management information,
9. The method according to claim 8, wherein the type of the file and a part of the actual data are always kept accessible in the cache memory. 10. A cache memory provided with a management information storage area, a storage device provided with a management information storage area, and a large-capacity storage device storing actual data are hierarchically connected, and are stored in the large-capacity storage device. The management information of each file is read in advance and stored in the management information storage area of the cache memory, and a part of the actual data of each file stored in the mass storage device is read in advance to manage the storage device. A method for controlling a hierarchical storage device, characterized by storing information in an information storage area.