JPH04363737A - Information storage system for auxiliary storage device - Google Patents

Abstract

PURPOSE:To carry out a writing and reading processing at a high speed. CONSTITUTION:When an information compressing means 61a compresses writing information, a writing means 61b writes the compressed information in several physical blocks among the plural physical blocks designated for writing according to the compressibility. A correspondence updating means 61c reloads logical blocks corresponding to the residual unused physical blocks in which the compressed information is not written to the logical blocks different from the above mentioned logical blocks. Moreover, the compressed information in the physical blocks is read by a reading means 61d, and the read compressed information is extended by an extending means 61e. Thus, the compression and extension of the writing or reading information can be operated in an auxiliary storage device 60.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention provides a function for compressing/expanding stored information in an auxiliary storage device that is externally attached to a computer using a virtual storage system and compensates for a lack of storage capacity in the main memory. The present invention relates to an information storage method of an auxiliary storage device provided therein.

0002

2. Description of the Related Art Conventionally, data stored in an auxiliary storage device has been stored as is without being compressed. However, the size of programs and data continues to increase, and there have been cases where the size of programs and data cannot be stored in auxiliary storage devices such as hard disks.

[0003] For this reason, data to be stored in the auxiliary storage device is now compressed in advance using a special program or the like before being stored in the auxiliary storage device.

[0004] Conventionally, as a technique in this type of field, there has been one as shown in FIG. 2, for example. The configuration will be explained below using figures.

FIG. 2 is a block diagram showing an example of the structure of a conventional information storage system of an auxiliary storage device. This information storage method is based on processors (CPs) connected to each other via a bus 11.
U) 12 and a computer 10 having a memory 13. Further, an auxiliary storage device 20 connected to the bus 11 is provided outside the computer 10.

A hard disk device 22 is provided in the auxiliary storage device 20 via a data writing/reading control device 21 connected to the bus 11 . In addition, the CPU
12 includes a file system which is a program for managing data write/read operations and data storage status of the auxiliary storage device 20, as well as a special program for data compression/expansion (LHarc version 1).
．． 13. LZEXE. EXE v0.91, JPEG
, MPEG, etc.).

Next, the operation will be explained.

In order to write data stored in the memory 13 to the auxiliary storage device 20, the data is first compressed in advance by the CPU 12 using a special program, and the compressed data is sent to the control device 21. The control device 21 writes the compressed data to a predetermined block (area) on the hard disk device 22 specified by the file system.

[0009] Furthermore, in order to read the compressed data written in the hard disk device 22 into the memory 13, the control device 21 reads data of a specified block from the file system and sends the data to the CPU 12. CPU1
2 decompresses the sent data using a special program and stores it in the memory 13.

0010

[Problems to be Solved by the Invention] However, in the information storage method having the above configuration, it is difficult to compress the data to be written to the hard disk device 22 or
In both cases, the CPU 12 in the computer 10 is used to expand the data read from the computer. Therefore, it is necessary to judge whether compression processing or decompression processing is necessary, or which processing to perform, and also to manage these processing and the order of access to the auxiliary storage device 20. There was a need.

[0011] For this reason, compared to the case where the auxiliary storage device 20 is normally accessed without performing compression processing and decompression processing, extra steps are required.
As a result, there is a problem in that the data writing/reading speed between the memory 13 and the hard disk device 22 is reduced.

[0012] Furthermore, since there are extra steps,
The CPU 12 cannot perform other tasks, and the CPU 12
There was also the problem that the usage efficiency of

The present invention provides an information storage system for an auxiliary storage device that solves the problem of the prior art, such as a decrease in data writing/reading speed.

[0014]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention has a plurality of physical blocks associated with logical blocks, and provides a write process for writing information from a main device into the physical blocks. and an auxiliary storage device that executes a read process to read the written information to the main device, and an auxiliary storage device that manages execution of the write process and read process by a file system provided in the main device. In the information storage system, the auxiliary storage device takes the following measures. That is, information compression means generates compressed information by compressing write information at a predetermined compression rate during the write process; writing means for writing the compressed information into an arbitrary physical block; and a logical block corresponding to an unused physical block remaining unwritten by the writing means among the specified plurality of physical blocks to another logical block. a correspondence changing means for rewriting the correspondence between the logical block and the physical block, a reading means for reading the compressed information in the physical block during the reading process, and a reading means for reading the compressed information read by the reading means. and an elongating means for elongating.

[0015]

[Operation] The present invention has the information storage method of the auxiliary storage device configured as described above, so that when the information compression means compresses the written information at a predetermined compression rate, the writing means writes the information according to the compression rate. Writes compression information to several physical blocks among the multiple physical blocks specified for the purpose. After the compression information is written, the association change means changes the logical blocks corresponding to the unused physical blocks that remain without being written to.
The logical block is rewritten to a different logical block, and the correspondence between the logical block and the physical block is changed.

Furthermore, during the read process, the read means reads the compressed information in the physical block, the decompressing means decompresses the read compressed information, and it is transferred to the main device side. This allows compression/expansion processing to be performed simultaneously with writing or reading information to the auxiliary storage device. Therefore, the above problem can be solved.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram of an information storage system of an auxiliary storage device showing an embodiment of the present invention. This information storage method is
It includes a computer (main device) 50 and an auxiliary storage device 60 connected thereto. The computer 50 has a CP
U51 is installed, and the CPU 51 is connected to a memory 53 such as a RAM (random access memory) via a bus 52.
It is connected to the.

The CPU 51 has an application 51a, which is a program, and a file system 51b. The application 51a is, for example, an auxiliary storage device 6.
The file system 51b is a program that instructs the file system 51b to perform data write/read processing for 0, and the file system 51b is a program that manages the data write/read processing in response to instructions from the application 51a. The CPU 51 has a function of controlling data writing and reading processes by operating according to these programs.

The auxiliary storage device 60 is composed of a control device 61 and a hard disk device 62 connected to the bus 52. The hard disk device 62 has a plurality of physical blocks that are actual storage areas, and also has a correspondence table in a specific area that holds the correspondence between the virtual logical blocks that are requested to access and the physical blocks that are actually accessed. .

[0020] The control device 61 has a file system 51b.
This is a device that controls data writing/reading processing for the hard disk device 62 in response to instructions from the hard disk device 62, and includes a correspondence table writing area 61A, information compression means 61a, and writing means 6.
1b, an association changing means 61c, a reading means 61d, and an expanding means 61e.

The correspondence table writing area 61A is an area such as a RAM that stores the correspondence table read from the hard disk device 62. The information compression means 61a is means for compressing written information at a predetermined compression rate during writing processing to generate compressed information, and the writing means 61b compresses a plurality of unused files in the hard disk device 62 specified in advance by the file system 51b. It is a means for writing the compression information into an arbitrary physical block according to the compression ratio among the used physical blocks.

[0022] The association changing means 61c changes a logical block corresponding to an unused physical block that remains unwritten by the writing means 61b from among the plurality of blocks specified in advance by the file system 51b into a different logical block. This means rewrites the correspondence table to change the correspondence between logical blocks and physical blocks. The reading means 61d is a means for reading compressed information in a physical block during a read process, and in addition, the decompressing means 61e is a means for decompressing information read from a physical block during a read process.

Next, the operation of the information storage system configured as described above will be explained.

First, the data writing processes (a) to (f) to the hard disk device 62 will be explained with reference to FIG. Note that FIG. 3 is an explanatory diagram of the operation of FIG. 1.

(a) Operation in step S1 The application 51a instructs the file system 51b to write the data stored in the memory 53 to the auxiliary storage device 60.
request to.

(b) Operation in Step S2 The file system 51b specifies a plurality of blocks in the hard disk drive 62 based on the amount of data requested to be written by the application 51a, and notifies the control device 61 of the specified blocks. At that time, the memory address of the data and the size of the data are also notified.

For example, if one block has a capacity of 4K bytes and the amount of write data is 38K bytes, the file system 51b writes 10 unused blocks from the managed hard disk drive 62. , and notifies the control device 61 of the block. At this time, assuming that ten blocks h to q shown in FIG. 4 are specified, these blocks h to q are registered as used areas.

(c) Operation in step S3 Subsequently, the control device 61 takes in data from the designated memory address in the memory 53, and the data is compressed by the information compression means 61a. Its compression ratio (compression ratio)
is determined by the data content and its compression algorithm. For example, if the compression rate is 50%, the 38K
Bytes of data are compressed to 19K bytes.

(d) In step S4, the operation control device 61 writes the compressed data to the hard disk device 62 using the writing means 61b. At that time, the data is written to some blocks among the plurality of blocks specified by the file system 51b according to the compression ratio. For example, since the data has been compressed to 19K bytes, it is written into five blocks h-l among the previously specified blocks h-q, as shown in FIG.

(e) In step S5, the association changing means 61c of the operation control device 61 assigns the five unused blocks as the five blocks following the maximum block M of the hard disk device 62, and assigns them to logical blocks and physical blocks. Rewrite the block correspondence table.

For example, in the previous writing, blocks m to q
5 blocks are unused, so these blocks m~q
The correspondence table is rewritten as blocks used to access blocks M+1 to M+5 shown in FIG. This indicates that a link A is established from the logical blocks M+1 to M+5, which do not actually exist, to the physical block that was unused in the previous writing. In this way, by rewriting the correspondence table, the logical block M that does not actually exist
When access to +1 to M+5 occurs, existing physical blocks m to q are accessed as alternative blocks.

Furthermore, when transferring compressed data from the hard disk device 62 to the memory 53 in response to a request from the application 51a, first the file system 51b
The memory area where the compressed data is read is the memory 53.
Ensure sufficient capacity. After that, the reading means 6 of the control device 61
Compressed data in a predetermined physical block of the hard disk device 62 is read by 1d. The read compressed data is transferred to a predetermined address in the memory 53 while being expanded by the expansion means 61e.

Note that during this read process, if it is necessary to transfer data to the memory 53 that exceeds the size of the memory area given by the file system 51b,
The control device 61 may request the necessary memory capacity from the file system 51b.

This embodiment has the following advantages.

(a) Since the data is compressed and stored in the auxiliary storage device 60, the hard disk device 62
In addition to being able to store data in an area smaller than the original data capacity, the data transfer speed between the memory 53 and the control device 61 can be increased according to the compression ratio even if the transfer speed of the hard disk device 62 is slow. can do. Therefore, a hard disk device 62 with a slow data transfer rate and low capacity can be used efficiently, so a low-cost hard disk device 62 can be used.

(b) The correspondence table shows the hard disk drive 62
, and the contents are transferred to the correspondence table writing area 61A in the control device 61 for use. Even if the content of the stored correspondence table is erased, it is only necessary to transfer it again from the hard disk device 62, and accurate processing becomes possible.

(c) Since the correspondence table manages all logical blocks and physical blocks, the physical blocks held in the correspondence table can be hidden from the file system 51b. This eliminates the possibility that the contents of the correspondence table will be erroneously rewritten by the file system 51b.

Note that the present invention is not limited to the illustrated embodiment, and various modifications are possible. For example, there are the following variations.

(1) In the above embodiment, the present invention is limited to reading and writing data requested by the application 51a, but it can also be applied to reading and writing executable code, for example.

(2) Instead of the hard disk device 62,
For example, a magnetic tape device or an optical disk device may be used.

(3) The plurality of physical blocks h to q specified in advance may be continuous areas or discontinuous areas.

[0042]

As described above in detail, according to the present invention, the auxiliary storage device is provided with information compression means, writing means, correspondence changing means, reading means, and decompression means, and information is written in the auxiliary storage device. Since the information or read information is compressed/expanded, it is no longer necessary to perform compression/expansion processing in the main device as in the past, and the extra steps used for compression/expansion processing can be omitted. Can be done. Therefore, the writing/reading speed is improved, and the main device can perform other tasks by replacing the omitted steps.
Can be used efficiently.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an information storage method of an auxiliary storage device showing an embodiment of the present invention.

FIG. 2 is a configuration diagram of an information storage method of a conventional auxiliary storage device.

FIG. 3 is an explanatory diagram of the operation in FIG. 1;

FIG. 4 is a diagram showing a storage format of the hard disk device in FIG. 1;

[Explanation of symbols]

50 Main device 60 Auxiliary storage device 61A Correspondence table writing area 61a Information compression means 61b Writing means 61c Correspondence change means 61d Reading means 61e Expansion means 62 Hard disk device

Claims (1)

[Claims] 1. A write process that has a plurality of physical blocks associated with a logical block, writes information from a main device to the physical block, and a read process that reads the written information to the main device. In the information storage method of the auxiliary storage device, the auxiliary storage device includes an auxiliary storage device that executes the write process and manages the execution of the write process and the read process by a file system provided in the main device. an information compression means for generating compressed information by compressing information at a predetermined compression rate; a writing means for writing compressed information; and a logical block corresponding to an unused physical block remaining unwritten by the writing means among the specified plurality of physical blocks, and rewriting the logical block to another logical block, and writing the logical block to another logical block. a mapping change means for changing the mapping with the physical block;
An information storage system for an auxiliary storage device, comprising: a reading unit for reading compressed information in the physical block during the reading process; and a decompressing unit for decompressing the compressed information read by the reading unit.