JPH04172544A - Virtual storage system - Google Patents

Abstract

PURPOSE:To increase a paging area during the execution of operation of a virtual storage system by preparing a page file in a user's area on the secondary storage unit as is similar to the preparation of an ordinary file and by preparing a page file effective flag to control a page file. CONSTITUTION:In the secondary storage unit 4, a page file 17 is newly prepared as is similar to the preparation of an ordinary file. Next, according to instructions of incorporating a page file, a control program newly prepares a bit map area 322 corresponding to the page file 17, that is, an entry corresponding to the bit map area 322 in a page table 340, and then initialized. Further, the entry 311a corresponding to area 322 for a management block 310 is secured, information of file 17 is set up, and further a pointer to area 322 is set up. Next, file 17 is opened so that it can be written and read, followed by making bit b2 of the page file effective flag 312 valid that indicates that the entry 311b corresponding to file 17 is valid in file 17.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a paging area on a secondary storage device in which a program is divided into pages of a fixed size and stored therein, while a paging area on a main storage device is The present invention relates to a virtual storage system provided with a management program 0.1 for managing a paging area.

[Prior Art] The virtual memory system was developed to allow each task to be executed without being aware of the storage capacity limitations of the main memory, and has recently been adopted in various computer systems. It's here.

This virtual memory system not only has a great effect when executing relatively large-scale tasks, but also maintains confidentiality by preventing the address spaces of other tasks from being referenced when tasks are processed in parallel. Maintain credibility
It plays an important role.

Figure 2 shows 11 virtual memory/computer functioning as a system/
A general configuration diagram of the stem is shown.

As shown in the figure, this computer 7 stem includes a /stem console 1, a microprocessor 2, a main storage device 3,
A secondary storage device 4, a floppy disk drive 5,
It is composed of a printer 6. In addition, input/output terminal 7
A plurality of terminal devices 8 are connected to the terminal device 8 as appropriate.

The system console 1 consists of a keyboard, a screen, etc., and is a device used by an operator to control the system.

The microprocessor 2 controls and manages this system, and the main storage device 3 is composed of a RAM and the like into which calculation programs and data are loaded.

The secondary storage device 4 is composed of a hard disk drive and the like that stores and saves calculation programs and other various information.

The floppy disk drive 5 is an external storage device using a floppy disk, and the printer 6 is a device for printing various information.

Now, in the computer system as described above, when a task is executed, the task program is first read from the secondary storage device 4 and loaded into the main storage device 3.

However, since there is a limit to the storage capacity of the main storage device 3,
It may not be possible to load all programs necessary for a task into the main storage device 3. In such a case, a virtual storage system that uses the secondary storage device 4 to compensate for the amount that cannot be loaded becomes effective.

In conventional virtual storage systems, the minimum necessary programs are loaded into the main storage device 3, and programs and data are loaded onto the main storage device 3 from the secondary storage device 4 each time the need arises. By transferring unnecessary programs and data from the main storage device 3 to the secondary storage device 4, programs are created on a logical storage device with almost unlimited capacity, and the storage space in this logical storage device is freed up. A virtual address is assigned to the main storage device 3, while a real address is assigned to the main storage device 3 to execute a predetermined process.

Furthermore, in the so-called paging-type virtual memory 7 system, a program is divided into pages of a fixed size (usually about 4 kilobytes), and allocation to the main storage device 3 is performed page by page. In this case, address conversion between virtual addresses and real addresses is performed using a page table. If the page does not exist in the main storage device 3, a page fault interrupt occurs, and the corresponding page is loaded from the secondary storage device 4 to the main storage device 3 by the control program.

If the capacity of the main storage device 3 becomes insufficient during arithmetic processing, the storage data on the main storage device 3 that is no longer needed is transferred to the secondary storage device 4 in page units. In this case, the content of that page may have been rewritten by calculation processing compared to when it was loaded, but as long as there is no problem, it will be transferred to the original page in the secondary storage device 4. Otherwise, it will be transferred to the original page in the secondary storage device 4. It is transferred to another free page (basing area) of device 4.

[Problems to be Solved by the Invention] Incidentally, in conventional virtual storage systems, the paging area on the secondary storage device 4 is usually provided separately from the area usable by the user of the computer system.

FIG. 3 shows a paging area in a conventional virtual memory/stem.

A management block 31 that manages the paging area 11 on the secondary storage device 4 and a bitmap area 32 that manages the free space of the paging area 11 are provided on the main storage device 3. The size of 11 is estimated when constructing the system, and the size is set when the secondary storage device 4 is initialized.

Therefore, the size cannot be changed during system operation, and if it becomes necessary to increase the paging area 11 due to an increase in the number of users or an increase in the amount of data, the paging area 11 that is currently in use in the user area 12 There is a problem in that after the user files and control program files have been temporarily evacuated from the user area, the operation of the system must be stopped and the secondary storage device 4 must be initialized again.

Furthermore, if you try to increase the paging area 11 while avoiding re-initialization of the existing secondary storage device 4, even though there is an unused area in the user area 12 of the existing secondary storage device 4. However, there is a problem in that a new secondary storage device 14 must be added, which increases costs.

The present invention was made in view of the above-mentioned circumstances, and when it becomes necessary to increase the paging area, if there is an unused area in the existing secondary storage device, that area can be used as the paging area. Therefore, it is an object of the present invention to provide a virtual storage system that can increase the paging area without stopping the system or adding a new secondary storage device.

[Means for Solving the Problems] A virtual storage system according to the present invention is provided with a paging area on a secondary storage device that stores a program divided into pages of a fixed size, and on the other hand, on a main storage device with the A management block is provided to manage the paging area, and the page file that constitutes the paging area in the secondary storage is created in a new format by having the same format as the file in the normal user area. Allows page files to be created sequentially.

In addition, a bitmap area for managing free space in units of page files is additionally created on the main storage device each time a new page file is created on the secondary storage device, and the bitmap area is used to manage the paging area. Make the necessary control program work areas dynamic.

Furthermore, the management block is equipped with a page file validity flag indicating whether or not each page file constituting the paging area can be used.

[Operation] According to the virtual storage system according to the present invention, when it becomes necessary to increase the baging area, if there is an unused area on the existing secondary storage device, the user on the secondary storage device By creating a new page file in the unused area in the same way as creating a normal file in the area, it is possible to increase the paging area during system operation. Through control, the increased paging area can be quickly transitioned to a usable state.

Therefore, it is possible to increase the paging area without stopping the system or adding a new secondary storage device.

Embodiment FIG. 1 is a block diagram of a microprocessor in a virtual storage system according to the present invention.

In this embodiment, the general configuration of the system is as follows:
As shown in the figure.

However, the microprocessor 2 in one embodiment includes:
As shown in FIG. 1, paging area addition instruction means 21
, virtual space creation means 22 , paging area embedding means 23 , secondary storage transfer means 24 , and secondary storage allocation means 25 are provided.

The paging area addition instruction means 21 is for cutting out a new paging area and issuing an additional instruction to the control program.

The virtual space creation means 22 creates a virtual space that the control program needs as a new management area.

The paging area incorporating means 23 incorporates the added paging area under the management of the virtual storage system and makes it usable.

The secondary storage transfer means 24 transfers unnecessary pages on the main storage device 3 to the secondary storage device 4.
.

The secondary storage allocation means 25 determines the location of the paging area to be transferred by the secondary storage transfer means 24.

Here, a virtual storage system which is an embodiment of the present invention will be described with reference to FIGS. 4 and 5.

FIG. 4 is a conceptual diagram of a main part of the embodiment, and FIG. 5 is a flowchart showing a processing procedure when increasing the paging area in the embodiment.

First, as shown in FIG. 4, it is assumed that a page file 16 is already provided in the secondary storage device 4. This page file 16 is used as a paging area. The size of the page files provided on the secondary storage device 4, including this page file 16, is not set and allocated at the time of initialization, but as described later, the user of the computer system can It can be created at any time by a certain file creation operation similar to that used when creating a file in the user area of the storage device 4.

The main storage device 3 is provided with a management block 310 that manages all page files on the secondary storage device 4.

This management block 310 includes entries 311a, 311b, 311 for each page file on the secondary storage device 4.
c, . . . are prepared, and a page file valid flag 312 is also provided. And each entry 311a, 311b, 311c,...
Information about the corresponding page file, such as file size and empty area size, is set.

Furthermore, the page file valid flag 312 has the most significant 1 bit b in the entry 311a, the second bit from the most significant one.
The 1st bit b is in the entry 311b, and so on, each internal l bit is in the aforementioned entries 311a, 311b.
b, 311c, and one entry each in =-. For example, whether the sign of a bit is "O" or "1" indicates whether or not the page file corresponding to that bit is valid as a paging area.

Further, the main storage device 3 is provided with a bitmap area for managing free space for each page file developed on the secondary storage device 4. In Figure 4, number 3
Reference numeral 21 indicates a bitmap area for the page file 16 described above, and reference numeral 322 indicates a bitmap area for the page file 17 described later.

The pinpoint map areas 321 and 322 allocate 1 bit to each page of the corresponding page file, and depending on whether the assigned focus code is "0" or "1", the corresponding page becomes an empty area. It shall be managed whether or not.

Management block 310 and bitmap area 321° 322
etc. exist in virtual space, so they are managed by the page table 340 provided on the main storage device 3, and when those areas are accessed, the microprocessor 2 (Fig. 2) The location on the main memory device 3 is indicated by the address translation mechanism.

Now, when increasing the paging area, follow the procedure shown in FIG.

The existing page file on the secondary storage device 4 is the page file 16, and a case where a new page file 17 is newly installed will be explained as an example.

First, a new page file 17 is added to the secondary storage device 4.
Create it just like a normal file.

However, restrictions on access rights (write rights, deletion rights, etc.) to the page file 17 are set in advance according to the status of the system user (step Sl).

Next, a page file installation instruction is issued to the control program. For example, a system administrator may input an instruction command from the system console 1 (Figure 2).
Step S2).

The control program that receives the instruction creates a new bitmap area 322 corresponding to the page file 17. Creation of a new bitmap area 322 is performed by creating a new entry for the bitmap area 322 on the page table 340.

One entry 341 for the bitmap area 322 on the page table 340 is required for each page.
Create a bitmap area 322 corresponding to the size (number of pages) for the page file 17 (step S3)
.

The created bitmap area 322 is initialized to a state where all bits are unused. Then, an entry 311b for the bitmap area 322 in the management block 310
is secured, information on the page file 17 is set, and a pointer to the rough view map area 322 is set (step S4).

Next, the page file 17 is opened and made ready for writing and reading (step S5).

Thereafter, bit b of the page file valid flag 312 indicating the validity of the entry 311b corresponding to the page file 17 among the entries in the management block 310 is set to a valid state, and this operation ends (step S6).

On the other hand, even during the above operation, transfer between the main storage device 3 (FIG. 2), which forms part of the virtual storage system, and the page file 16 already installed in the secondary storage device 4 is being executed in a timely manner. Management block 3
The determination is made based on the page file validity flag 312 of No. 10.

For example, how to determine the page file to use:
It is conceivable to look at the valid flag 312 and select the one with the most free space among the valid page files. In a system that manages page files using such a page file determination method, when the above-described step S6 is performed, the newly added page file 17 immediately becomes usable as part of the paging area.

According to the virtual storage system of the embodiment as described above, when it becomes necessary to increase the paging area, if there is an unused area on the existing secondary storage device 4, By creating a new page file in the unused area in the same way as creating a normal file in the user area, it is possible to increase the paging area during system operation, and it is also possible to increase the paging area during system operation. Control by the flag 312 allows the increased paging area to be quickly transitioned to a usable state.

Therefore, it has become possible to increase the paging area without stopping the system or adding a new secondary storage device.

[Effects of the Invention] As is clear from the above description, according to the virtual storage system according to the present invention, when it becomes necessary to increase the paging area, if there is an unused area on the existing secondary storage device, If so, you can increase the paging area during system operation by creating a new page file in that unused area, just as you would create a normal file in the user area on the secondary storage device. In addition, by controlling the page file valid flag, the increased paging area can be quickly transitioned to a usable state.

Therefore, it has become possible to increase the paging area without stopping the system or adding a new secondary storage device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a microprocessor according to an embodiment of the present invention, FIG. 2 is a configuration diagram of a computer system that is a virtual storage system according to an embodiment, and FIG. 3 is an explanation of a paging area in a conventional virtual storage system. FIG. 4 is a configuration diagram of a main part of an embodiment of the present invention, and FIG. 5 is a flowchart showing a processing procedure of a main part in the embodiment. 1...System console, 2...Microprocessor, 3...Main storage device, 4...
...Secondary storage device i, 16.17...Page file, 21...Paging area addition instruction means, 22...Virtual space generation means, 23...・
- Paging area incorporation means, 24...Secondary storage transfer means, 25...Secondary storage allocation means, 3
10... Management block, 311a. 311b, 311c... End 'J, 312.
...Page file valid flag, 321, 322
...Bitmap area, 340...Page table, 341...Entry. Figure 1 of 7'U19 of my 'Ja7' a Nanatsu in one embodiment of the present invention

Claims (1)

[Scope of Claims] A virtual paging area is provided on a secondary storage device to store a program divided into pages of a fixed size, and a management block is provided on the main storage device to manage the paging area. In the storage system, the page file constituting the paging area on the secondary storage device has a format similar to that of a file in a normal user area, so that new page files can be created sequentially, and the above-mentioned On the main storage device, a bitmap area for managing free space in units of page files is additionally created each time a new page file is installed on the secondary storage device, and the bitmap area necessary for managing the paging area is created on the main storage device. A virtual memory characterized in that a work area of a control program is made dynamic, and the management block is equipped with a page file valid flag indicating whether or not each page file constituting the paging area can be used. system.