JP2535584B2 - Real memory fixed processing computer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] In a virtual storage system computer that allocates a real storage area to a virtual storage area, a processing method for fixing the allocation state for a required period is described as a high-speed real storage fixed processing method. For the purpose, the real storage area on the main storage is allocated to a required virtual storage area, and a real storage management unit that manages to release the allocation is provided, and the virtual storage area to which the real storage area is allocated is accessed. In a computer that executes a program including a kernel program, a real storage fixed mode display that can be set to a predetermined state by the kernel program is provided, and the real storage management unit indicates the real storage area assigned to the virtual storage area. Whether or not the process of canceling the allocation state can be executed is identified by the setting state of the real memory fixed mode display.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method for fixing an allocation state invariant for a required period in a virtual storage system computer that allocates a real storage area to a virtual storage area.

[Conventional technology]

FIG. 3 is a block diagram showing an example of the configuration of a computer. In the so-called virtual memory type computer, programs and data of, for example, all areas of the virtual memory space are stored in the external storage device 1.
The real storage area 4 in the main memory of the processing device 2 is divided and allocated to the required virtual storage area in the virtual space 3 and the program or data of that portion is stored in the real storage area 4 from the external storage device 1. By loading the processing device 2
In, it becomes possible to actually access the virtual storage area.

Each real storage area 4 is a storage area obtained by dividing the main storage into, for example, pages of a certain size, and the real storage management unit 5 manages these real storage areas and allocates them to virtual storage areas as is known. For the real storage area, an address conversion unit called a page table or the like showing the correspondence between virtual addresses and real addresses is set.

When a program loaded and executed in the real storage area 4 tries to access the virtual storage area and a state in which the area is not loaded in the real storage area (this is called a page fault state) is detected, an interrupt occurs, etc. The means is notified to the real memory management unit 5.

The real storage management unit 5 determines an unallocated real storage area,
It is assigned to the virtual storage area of the access request, and the information of that portion is loaded from the external storage device 1 to make it accessible as described above.

Further, in this case, if all the real storage areas have already been allocated, a well-known appropriate logic is used to select the real storage area of a predetermined condition from among the already allocated areas and allocate it to the virtual storage area. After performing the processing for canceling the access, the virtual storage area having the access request is allocated as described above.

Execution of the program that encounters the page fault is suspended until it becomes accessible at least as described above, so the program saves the control information necessary for resuming execution and waits until it becomes executable. become.

As is well known, there are various programs called, for example, kernel primitive routines, which are called by a predetermined request from an application program in order to execute a service provided by an operating system, and which control the lowest layer. .

The program for each service of this kernel primitive routine performs processing that ends in a relatively short time, so all real storage areas are allocated to the necessary virtual storage areas, and execution interruption due to page faults is not possible. As a configuration that does not occur, the speed of the process is increased by adopting a configuration that does not consider saving of the restart control information and interference by other programs executed during the interruption.

Therefore, each program 6 of the kernel primitive routine, as shown in the flow of processing in FIG. Is requested to request fixing of the real memory, and the real memory managing unit 5 executes the real memory fixing process in processing step 11.

The real storage fixing process checks whether the real storage area is already allocated to the specified virtual storage area and checks all the areas one by one, allocates the real storage areas to all and makes them accessible, and fixes each allocated real storage area. This is the process of setting the status. It is necessary for the real memory management unit 5 to perform this process for each management unit of the real memory, and in particular, the real memory fixing process of step 11 requires a considerable processing time for checking.

The fixed state is a state that prohibits the de-allocation of the real storage area in which the fixed state is set, and the fixed release request is issued for the real storage area in which the fixed state is set in the management information of the real storage. Until there is, the real storage management unit 5 guarantees that the allocation state is maintained.

After the fixed processing is completed in the real memory management unit 5, the processing of the kernel primitive routine is executed in processing step 12,
When the processing for accessing the fixed area is completed, the real memory management unit 5 is requested to release the real memory fixation in processing step 13, and the fixed state of the area specified in processing step 14 is released.

[Problems to be Solved by the Invention]

As described above, the kernel primitive routine requests the real memory fixing to the real memory management unit 5 at the beginning of execution so as not to cause a page fault, and performs the fixed processing. However, in most cases, the virtual memory area is For example, a real storage area, which is the service request source area, has already been allocated.

If all the required areas have been allocated, the real storage management unit 5 is requested to transfer control as described above, and the real storage management unit 5 individually fixes and fixes each area. The cancellation process is a redundant process, and it is desirable to eliminate such overhead.

An object of the present invention is to reduce the overhead and speed up the real memory fixed processing method.

[Means for solving the problem]

 FIG. 1 is a block diagram showing the configuration of the present invention.

In the system for loading the programs and data of the virtual storage space held in the external storage device 1 in the figure to the real storage area 4 of the processing device 2 and executing them, the real storage fixed mode display 21 in which each program can be set in the processing device The real memory management unit 20
In the process of allocating a real storage area to a virtual storage area, the real storage fixed mode display 21 identifies whether or not the real storage area can be deallocated.

[Work]

The real memory management unit 20 executed by the processing device 2 manages the real memory area on the main memory to be allocated to a required virtual memory area and released.

The real storage fixed mode display 21 provided in the processing device 2 can be set by a program executed by the processing device 2, and displays whether or not the real storage fixed mode is set.

The real storage management unit 20 tests the real storage fixed mode display 21 when the real storage area allocated to the virtual storage area needs to be released, and when the real storage fixed mode is set, the real storage fixed mode display 21 is allocated. Only when the release mode is not executed and the real memory fixed mode is not set, the release process is executed if other required conditions are satisfied.

With the above processing method, in a program in which it is possible to perform the processing by prohibiting the deallocation of the area where the real memory is already allocated, it is only necessary to set the real memory fixed mode display 21, and the individual area to be used Since it is no longer necessary to request and execute the fixing and releasing the fixing of the real storage management unit 20,
Processing time is reduced.

〔Example〕

In FIG. 1, the parts denoted by the same reference numerals as those in FIG. 3 are the same as those in the conventional system, and the real memory management unit 20 has the functions described below, except that the conventional real memory management unit 5 is used. Similarly to the above, the real storage area in the main storage is allocated to a required virtual storage area, and management for canceling the allocation is executed. Even when the real memory fixing function according to the present invention is provided, the function of setting the fixed state for each real memory area and fixing the same is the same as in the case of the above-mentioned conventional case, for the use as described later and other cases. Needed for.

According to the present invention, the kernel primitive routine of the above example changes the processing part relating to the real memory fixing, and the program 22 thereof is first provided in the processing device 2 in the processing step 30 as shown in the processing flow of FIG. The memory fixed mode display 21 is set to the actual memory fixed mode.

The real memory fixed mode display 21 is set in a storage area of, for example, the main memory of the processing device 2 so that the real memory management unit 20 can read the real memory fixed mode display 21, and displays the real memory fixed mode in the ON state, for example. Display non-fixed mode in the off state. If necessary, the real memory fixed mode display 21 is used as a counter, for example, the non-fixed mode is set to "0", and the count value "1" or more is displayed as the real memory fixed mode. You may make it count up / down only by "1".

Next, in process step 31, a temporary access is executed for a necessary virtual storage area by a predetermined instruction to check whether or not a real storage area is allocated.

As a result, if all the necessary areas have been allocated to the real storage areas, the processing of kernel primitives that require access to those areas is executed in processing step 32, and when the processing is finished, the real storage fixed mode display 21 is displayed in processing step 33. Reset (or count down) to non-fixed mode.

Therefore, if there is no unallocated area,
The process of the kernel primitive routine is performed without performing the control transfer with the real memory management unit 20 and the real memory fixed process as in the related art.

However, when it is necessary to release the allocation state, the real memory management unit 20 tests the real memory fixed mode display 21, does not execute the deallocation processing in the real memory fixed mode, and only in the non-fixed mode, other Since the release processing is executed if the required condition is satisfied, the purpose of fixing the real memory is achieved by the above.

As a result of the check in processing step 31, if there is a real storage area unallocated area in the required virtual storage area, after resetting the real storage fixed mode display 21 to the non-fixed mode in processing step 34, the process shown in FIG. The conventional process starting at process step 10 is started.

〔The invention's effect〕

As is apparent from the above description, according to the present invention, in the processing for fixing the real storage allocation state of the virtual storage system computer for a required period, if it is sufficient to simply deallocate the real storage, Since it is only necessary to set the real memory fixed mode display, there is a remarkable industrial effect that the processing time is reduced and the processing efficiency of the computer is improved.

[Brief description of drawings]

 FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a flow chart of the process of the present invention, FIG. 3 is a block diagram showing a conventional configuration example, and FIG. 4 is a flow diagram of the conventional process. In the figure, 1 is an external storage device, 2 is a processing device, 3 is a virtual space, 4 is a real storage area, 5 and 20 are real storage management units, 6 and 22 are programs, 21 is a real storage fixed mode display, 10- 14, 30 to 34 indicate processing steps.

Claims (1)

(57) [Claims] 1. A real storage management unit (20) for allocating a real storage area (4) on a main memory to a required virtual storage area, and for managing the release of the allocation, the real storage area being allocated. In a computer that executes a program (22) including a kernel program that accesses the virtual storage area, a real storage fixed mode display (21) that can be set to a predetermined state by the kernel program is provided, and the real storage management unit ( 20) indicates whether or not the real storage area (4) allocated to the virtual storage area can be released from the allocated state, in the real storage fixed mode (21).
A real memory fixed processing computer characterized by being identified according to the setting state of.