JPH08278910A - Method for information processing system and secondary storage device - Google Patents

Abstract

PURPOSE: To perform the maintenance process for the secondary storage device without lowering the efficiency of file access. CONSTITUTION: The information processing system which reads in a file stored in the secondary storage device 103 and accesses the file is equipped with a secondary storage device maintenance part 307 which performs the maintenance process for the secondary storage device 103, a data writing switching part 303 which writes data in a secondary storage device 104 for maintenance at a request to write the data in the secondary storage device 103 in parallel to the maintenance process by the secondary storage device maintenance part 307, and a data reading switching part 304 which reads data out of the secondary storage device 103 or secondary storage device 104 for maintenance at a request to read the data out of the secondary storage device 103 in parallel to the maintenance process by the secondary storage maintenance part 307.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing system for reading a file stored in a secondary storage device and realizing file access.

[0002]

2. Description of the Related Art Generally, in an information processing system to which a secondary storage device (a magnetic disk device, an optical disk device, a magneto-optical disk device, etc.) storing a file is connected, a necessary portion of the file is buffered in a main memory. By doing so, file access is realized.

Further, in general, a maintenance process is performed on the secondary storage device connected to the information processing system as needed. For example, the maintenance process includes checking the validity of the file, backing up the file stored in the secondary storage device, and detecting the presence or absence of a bad block.

In the conventional information processing system, when maintenance processing is performed on the secondary storage device, file access to the secondary storage device by other processing is prohibited. That is, when the data buffered in the main memory for file access is updated and the updated data is written back to the secondary storage device during maintenance and inspection,
This is because the contents of the file may be changed or the file may be destroyed, which may affect the maintenance process.

[0005]

As described above, in the conventional information processing system for reading and processing a necessary portion of a file, when the maintenance processing is performed on the file stored in the secondary storage device, the file is temporarily stored. File access was prohibited.

Therefore, when the data in the secondary storage device is needed during the maintenance process, or when there is a file access request for saving the data in the secondary storage device, those data are stored. The process will wait until the maintenance process is completed. That is, in the conventional information processing system, the efficiency of file access is lowered by the maintenance process for the secondary storage device.

The present invention has been made in consideration of the above circumstances, and an information processing system and a secondary processing system capable of executing maintenance processing for a secondary storage device without reducing the efficiency of file access. It is an object to provide a maintenance method for a storage device.

[0008]

SUMMARY OF THE INVENTION The present invention is an information processing system for processing a file stored in a secondary storage device to realize a file access, the secondary storage device performing maintenance processing of the secondary storage device. Maintenance means and a maintenance target of the secondary storage device maintenance means in parallel with the maintenance processing of the secondary storage device by the secondary storage device holding means in response to a data write request to the secondary storage device. Data writing means for writing data to a storage means that does not become a memory, and a maintenance process by the secondary storage device maintenance means for the secondary storage device in response to a data read request to the secondary storage device. ,
It is characterized by comprising a data reading means for reading data from the secondary storage device or the storage means.

Further, after the maintenance processing of the secondary storage device by the secondary storage device maintenance means is completed, the data written in the storage means by the data writing means is transferred to a predetermined file position of the secondary storage device. It is characterized in that it further comprises a data write-back means for writing back data to.

When the storage means is connected to the system, the storage means connection means is provided for detecting whether or not the storage means is connected to the system. In addition, the data writing unit and the data reading unit perform the operation.

[0011]

According to this structure, when there is a file access request for writing to the secondary storage device in which maintenance processing is being executed, maintenance storage means for writing during maintenance processing, that is, When a write access is made to a storage area that is not subject to maintenance processing or a secondary storage device for maintenance, and there is a file access request for reading, storage means that includes the latest contents written during maintenance processing Alternatively, if there is no corresponding data in the storage means, the data is read from the secondary storage device. That is, during the maintenance process,
Since only the read that does not affect the maintenance process is executed,
File access to the secondary storage device can be executed in parallel without waiting for the completion of maintenance processing.

Data to be written to the secondary storage device during the maintenance process should be temporarily stored in the storage means, and after the maintenance process is completed, the original writing of the secondary storage device should be executed. It is written back to the specified file position. Therefore, even if data is written during the maintenance process, the data consistency can be maintained.

Further, by providing means for detecting that the maintenance secondary storage device is connected to the system, a file access request is made in response to whether the maintenance secondary storage device is connected or not. The target of writing or reading can be switched.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the information processing system according to this embodiment. As shown in FIG. 1, in the information processing system of the present embodiment, the processor 101 uses the bus 10
A secondary storage device (magnetic disk device, optical disk device, magneto-optical disk device, etc.) 103 is connected via 2.

The processor 101 accesses a file stored in the secondary storage device 103 via the bus 102. When executing the maintenance process for the secondary storage device 103, the maintenance secondary storage device 104 is connected to the bus 102.

The processor 101 realizes various functions by executing a program stored in the main memory 101b by the CPU 101a. In the main memory 101b, various data and the like are appropriately stored in addition to the OS (operating system), application programs, and C
It is executed by the PU 101a. In addition, when a file stored in the secondary storage device 103 is accessed, the necessary part of the file is stored in the main memory 10.
It is buffered in the buffering area 1b.

The operating system operating on the processor 101 includes a file subsystem (program) 201, a storage device connection program 202, a data writing switching program 203, a data reading switching program 204, and a data writing back program 20.
5. A data access restoration program 206 is included.
A secondary storage device maintenance program 207 is included as one of the application programs. By operating each program on the processor 101, each processing function (file subsystem 301, storage device connection unit 302, data writing switching unit 303, data reading switching unit 304, data writing back unit 305, data access restoration unit 306 , The secondary storage device maintenance unit 307) is realized.

The file subsystem 301 controls normal input / output to / from a file stored in the secondary storage device 103. During maintenance processing, each processing function unit is controlled to perform file access and maintenance processing in parallel. File access (without waiting for the maintenance process to complete).

The storage device connection unit 302 recognizes that the maintenance secondary storage device 104 is connected to the system and notifies the file subsystem 301.

The data writing switching unit 303 switches a file write request from the file subsystem 301 to the secondary storage device 103 during the maintenance process to an operation to the maintenance secondary storage device 104 and executes writing. To do. Also, the data writing switching unit 303
When executing writing, the
A data correspondence table 104a is created by associating information (block number) indicating the data to be written with the data to be actually written to the maintenance secondary storage device 104, and the maintenance secondary storage is created. It is stored in the device 104.

The data read switching unit 304 switches and executes a file read request from the file subsystem 301 during execution of maintenance processing to either the operation of the secondary storage device 103 or the maintenance secondary storage device 104. To do. The data read switching unit 304 determines that the content of the file to be read is the secondary storage device for maintenance 1
If it is stored in 04, it is read from the maintenance secondary storage device 104. If it is not stored in the maintenance secondary storage device 104, it is read from the secondary storage device 103.

The data write-back unit 305 stores a file stored in the maintenance secondary storage device 104 in response to an instruction from the secondary storage device maintenance unit 307 (indicating completion of maintenance processing for the secondary storage device 103). According to the correspondence relationship of the data stored in the data correspondence table 104a,
The data is written back to a predetermined position in the secondary storage device 103.

The data access restoration unit 306 changes the file access by the file subsystem 301 to a normal operation for the secondary storage device 103 in response to the data write back completion notification from the data write back unit 305.

The secondary storage device maintenance unit 307 executes maintenance processing for the secondary storage device 103 requested by execution of the application program, for example, file validity check, backup, detection of presence / absence of bad block. Then, it has a drive function for executing a file access that does not depend on the file subsystem 301. When the maintenance process is completed, the secondary storage device maintenance unit 307 notifies the data write-back unit 305.

Next, the operation of this embodiment will be described.

First, a normal file access operation to the secondary storage device 103 will be described with reference to FIG. FIG. 2 shows a state of file access to the secondary storage device 103 in the information processing system of this embodiment.

For example, assume that the secondary storage device 103 stores a file A composed of data blocks m and n and a file B composed of data blocks x and y. As shown in FIG. 2, the file subsystem 301 buffers each block of files A and B in the main memory 101b. When the data blocks n and y buffered in the main memory 101b are changed, the file subsystem 301 transfers the changed buffer data to the file A on the secondary storage device 103.
Write back to the proper position on B.

Next, the operation of the maintenance process for the secondary storage device 103 will be described with reference to FIG. FIG. 3 shows the information processing system of the present embodiment.
The maintenance secondary storage device 104 is connected when performing the maintenance process for the secondary storage device 103.

Here, while the maintenance processing for the secondary storage device 103 is being executed by the secondary storage device maintenance unit 307, the data block of the file stored in the secondary storage device 103 (data block n of the file A). ) Will be described with reference to the flowchart shown in FIG.

First, when the file subsystem 301 receives a request for writing the data block n of the file A, the storage subsystem 302 determines whether the maintenance secondary storage subsystem 104 is connected to the system. Yes (step S1). When the maintenance secondary storage device 104 is not connected, the normal access, that is, the file access is executed after the maintenance process is completed (step S2).

On the other hand, when the maintenance secondary storage device 104 is connected to the system, the storage device connection unit 302 detects it and notifies the file subsystem 301 of it.

When the maintenance secondary storage device 104 is connected, the file subsystem 301 reads the file (data block n) from the data read switching unit 3
04 (step S3).

When the file subsystem 301 requests reading of the data block n, the data read switching unit 304 determines whether or not the data block n exists in the maintenance secondary storage device 104 (step S).
4). That is, since the data writing switching unit 303 writes to the secondary storage device 104 for maintenance during the maintenance process to the secondary storage device 103 (details will be described later), the latest file contents are stored in the secondary storage device 103. It exists in the next storage device 104. Therefore, if the data block of the corresponding file exists in the secondary storage device for maintenance 104, the data read switching unit 3
04 reads the corresponding data block from the secondary storage device for maintenance 104 (step S5).

On the other hand, when the corresponding data block does not exist in the maintenance secondary storage device 104, the data read switching unit 304 reads the data block from the secondary storage device 103. Although the secondary storage device maintenance unit 307 is performing maintenance processing on the secondary storage device 103, the data block is read without waiting for the completion of this work. That is, since only reading is executed from the secondary storage device 103, the contents of the file are not changed and the maintenance process is not affected.

When the file subsystem 301 reads in the data block n via the data read switching unit 304, it buffers it in the main memory 101b.
The data of the data block n buffered in the main memory 101b is changed by, for example, the process based on the application program (step S7).

Next, the file subsystem 301 writes back the changed data block n, and during the maintenance process for the secondary storage device 10, the data writing switching unit 3
03 (step S8).

When the file subsystem 301 requests writing of the data block n, the data writing switching unit 303 executes writing to the maintenance secondary storage device 104 (step S9).

At this time, the data writing switching unit 303
Creates a data correspondence table 104a indicating which data block in the secondary storage device 103 originally corresponds to the data written in the maintenance secondary storage device 104, and The data is stored in the next storage device 104 (step S10).

As shown in FIG. 5, the data correspondence table 104a includes the block number written in the maintenance secondary storage device 104 and the original storage device 103.
The block number to be written to is stored in association with each data block. For example, it is assumed that the block number of the data block n in the maintenance secondary storage device 104 is “7”, and the block number to be originally written in the secondary storage device 103 is “5”.

As described above, during the maintenance process for the secondary storage device 103, the file subsystem 301 reads the file, and the data read switching unit 304
The file writing is performed via the data writing switching unit 303. For example, if there is a write request to the data block y of the file B,
In the same manner as described above, the data is read from the secondary storage device 103, changed, and then written to the maintenance secondary storage device 104. At that time, as shown in FIG. 5, the block number for the maintenance secondary storage device 104 and the block number for the secondary storage device 103 are associated with each other in the data correspondence table 104a of the maintenance secondary storage device 104. Stored.

Further, the data read switching unit 304 is
When there is a read request for the data block n again, the changed data is the secondary storage device for maintenance 104.
Data is read from the maintenance secondary storage device 104 and returned to the file subsystem 301.

When the maintenance process for the secondary storage device 103 is completed, the secondary storage device maintenance unit 307 notifies the data access write-back unit 305 that the maintenance is completed.

The data access write-back unit 305 responds to the notification from the secondary storage device maintenance unit 307, and stores the data written in the maintenance secondary storage device 104 in the secondary storage device 1.
Write back to 03. That is, since the writing to the secondary storage device 103 during the maintenance process is performed to the maintenance secondary storage device 104, it is written back to the secondary storage device 103 to be originally written.

The data write-back unit 305 has a data correspondence table 104a stored in the secondary storage device 104 for maintenance.
The data stored in the maintenance secondary storage device 104 is written in the secondary storage device 103 based on the correspondence relationship of the data registered in.

For example, the data block n of the file A stored as the block number "7" in the maintenance secondary storage device 104 is stored in the data correspondence table 104a as shown in FIG. Number "5"
Is associated with. Therefore, the data write-back unit 30
5 is a block number “7” in the secondary storage device 104 for maintenance.
The data stored as is written back to the secondary storage device 103 at a predetermined position corresponding to the block number “5”. The data write-back unit 305 executes write-back with respect to all the data in which the correspondence relationship of the block numbers is stored in the data correspondence table 104a.

When the data write-back section 305 completes the write-back of all the data, it notifies the data access restoration section 306 of the write-back completion. The data access restoration unit 306, for the file subsystem 301,
The maintenance secondary storage device 104 is disconnected from the system, and a notification is issued to execute the file access as usual.
The file subsystem 301, which has received the notification from the data access restoration unit 306, makes subsequent file access requests to the secondary storage device 103.

In this way, in response to a file access request to the secondary storage device 103 during maintenance processing, reading of a file whose file contents are not changed is executed without waiting for completion of maintenance processing, and writing is performed. To the secondary storage device for maintenance 104, and after the maintenance process is completed, the data is written back to a predetermined position in the secondary storage device 103 where it should be written. Therefore, it is not necessary to wait for the file access due to the maintenance process, so that the file access can be performed efficiently.

Further, when reading the file during the maintenance process, it is first judged whether or not the target data exists in the maintenance secondary storage device 104, and if it exists, it is the latest content written during the maintenance. , Secondary storage device 10 for maintenance
It is read out from 4 and used for processing. That is, normal processing can be performed regardless of execution of maintenance processing.

In the above embodiment, the maintenance secondary storage device 104 is connected to perform the maintenance process for the secondary storage device 103. However, the maintenance secondary storage device 104 is not used. You can also do it.

For example, it is possible to determine that a maintenance area is provided in the secondary storage device 103 and the maintenance area is secured when a file access request is made during maintenance processing or when maintenance processing is executed during file access. In this case, writing during maintenance processing is performed on the maintenance area, and after the maintenance processing is completed, the data of the file written in the maintenance area is written back to the original position. Further, the maintenance process is not performed on the maintenance area.

Therefore, in this case, the storage device connecting section 3
02 becomes unnecessary. The maintenance area may be reserved in advance by predicting the storage capacity used during the maintenance processing, or may be dynamically secured before the maintenance processing is started.

Further, in the above-mentioned embodiment, it is explained that one processor 101 executes maintenance processing and data reading / writing with respect to the secondary storage device 103, but it can be applied to a multiprocessor system.

In this case, maintenance processing is executed for the secondary storage device 103 via the secondary storage device maintenance unit operating on a certain processor, and file access is executed by a file subsystem operating on another processor. can do. Further, by performing maintenance processing on the secondary storage device 103 via the file subsystem, the secondary storage device maintenance unit can be accessed by accessing the secondary storage device 103 in parallel with the file subsystem on one processor. Can be unnecessary. However, in either case, during the file access for maintenance processing by one processor, access control is performed to allow the file access by another processor.

[0054]

As described in detail above, according to the present invention, a file access request during maintenance processing can be executed without waiting for the completion of maintenance processing. It is possible to execute the file without reducing the efficiency of file access.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an information processing system according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining a normal file access operation in this embodiment.

FIG. 3 is a diagram for explaining a file access operation during maintenance processing according to the present embodiment.

FIG. 4 is a flowchart for explaining a file access operation during maintenance processing according to the present embodiment.

FIG. 5 is a data correspondence table 104a in this embodiment.
The figure which shows an example of the content of.

[Explanation of symbols]

101 ... Processor, 102 ... Bus, 103 ... Secondary storage device, 104 ... Maintenance secondary storage device, 101a ... CP
U, 101b ... Main memory, 301 ... File subsystem, 302 ... Storage device connecting section, 303 ... Data writing switching section, 304 ... Data reading switching section, 305 ...
Data write-back unit, 306 ... Data access restoration unit, 3
07 ... Secondary storage device maintenance section.

Claims (4)

[Claims] 1. An information processing system for processing a file stored in a secondary storage device to realize file access, comprising: a secondary storage device maintenance means for performing maintenance processing of the secondary storage device; and the secondary storage device. In response to a data write request to the device, in parallel with the maintenance processing of the secondary storage device by the secondary storage device holding means, data is written to the storage means not subject to maintenance by the secondary storage device maintenance means. Data writing means for writing, and in response to a data read request to the secondary storage device, in parallel with the maintenance processing by the secondary storage device maintenance means for the secondary storage device, the secondary storage device or the An information processing system comprising: a data reading unit that reads data from a storage unit. 2. The data written in the storage unit by the data writing unit after the secondary storage unit maintenance unit finishes the maintenance process of the secondary storage unit is stored in a predetermined file position of the secondary storage unit. The data write-back means for writing back data to the device is further provided.
Information processing system described. 3. A storage device connecting means for detecting whether or not the storage device is connected to the system, wherein the storage device connecting device detects that the storage device is connected to the system. 3. The information processing system according to claim 1, wherein the data writing unit and the data reading unit execute the operation. 4. An information processing system for processing a file stored in a secondary storage device to realize file access, comprising: a maintenance process for the secondary storage device in response to a data write request to the secondary storage device. In parallel with this, data writing is performed to write data to the storage means that is not the maintenance target, and in parallel with the maintenance process for the secondary storage device in response to a data read request to the secondary storage device. If the data corresponding to the storage means exists, the data is read from the storage means, and if the data corresponding to the storage means does not exist, the data is read from the secondary storage device. After the maintenance process for the secondary storage device is completed, the data written in the storage means is stored in the secondary storage device in a predetermined manner. A method for maintaining a secondary storage device, which is characterized in that the file is written back to the file position.