JP2636745B2 - Paging processing method and method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and system for paging processing in a virtual storage system.

[0002]

2. Description of the Related Art A conventional paging processing method mainly uses an LRU (Least Rec) method as a method for selecting a page to be paged out in order to reduce the number of page faults.
ently Used method). This LRU
According to the law, pages that have not been used in main memory for a certain period of time are selected and paged out on the assumption that they will not be used in the near future.

[0003] Also, as a known technique,
In the 84 “paging processing method”, a page replacement area is provided in the main memory, and paging processing is performed continuously by performing page-in / page-out as a series of operations, thereby realizing high-speed paging. The garbage collector page control method of 1987 discloses an unnecessary page invalidation and a page out of an unaccessed page, thereby realizing an efficient paging process. 62-281
The 040 “page management method” distributes a program module to a paging register for managing page-in / page-out in advance and performs paging processing, which is effective for a program having many branches. Japanese Patent Application Laid-Open No. 2-238535 discloses a method of paging efficiency by dynamically determining the number of pages in / out based on the history of page access time interval data. is there.

[0004]

However, the conventional L
According to the RU method, a page to be paged out is determined to be a page that has not been used for a certain period of time. Therefore, in a program that naturally uses an unused page, page faults frequently occur and the execution speed is increased. On the contrary, there is a problem that it is slow.

In each of the above-mentioned known techniques, the efficiency or speed of paging processing corresponding to the occurrence of a page fault is improved. When the same program is executed again, the processing speed of the paging processing does not change. Efficiency cannot be expected.

An object of the present invention is to provide means for realizing the efficiency and speeding up of the paging process based on the history table of the paging process at the time of the previous program execution when the same program is executed again. .

[0007]

According to the present invention, there is provided a paging processing method for a virtual storage system, comprising the steps of: recording a page history order of a program accessed when one program is executed; Is in auxiliary memory when trying to execute again
The pages to be loaded from the main memory in the order of the history
Selecting the size of the page storage unit, and when a page fault accessing the page stored in the auxiliary storage but not read into the execution page storage unit occurs, the page is used next to the order of the history. There is a step of excluding a page of the size of the execution page storage unit in the main memory from the page, page-out other pages, and page-in from a page of the size of the execution page storage unit.

In the step of page-in of the page, when a page fault occurs, the page from the next used page in the order of the history to the last page currently stored in the execution page storage unit is stored. Page out of the other pages and page in the page portion requested to be accessed.

[0009]

[0010]

Further, the paging processing method according to the present invention is a paging processing method for a virtual storage system, wherein means for recording, in a first access page history table, the order of pages of a program accessed when one program is executed. , the order of pages to be loaded from the auxiliary memory in the <br/> when trying to run the same program again the history
Means for selecting the size of the execution page storage unit in the main storage, and a page fault that accesses a page stored in the auxiliary storage but not read into the execution page storage unit. From the access page history table, the next page to be used in order from the next page is excluded from the pages of the size of the execution page storage unit in the main storage, and the other pages are paged out, and the pages of the size of the execution page storage unit are removed. There is a means to page in from.

Further, the means for page-in the page, when a page fault occurs, starts from the next page to be used in the order of the first access page history table and returns to the last page currently stored in the execution page storage unit. Means are provided for page out of the remaining pages except for the page and page in of the page portion requested to be accessed.

[0013]

[0014]

[0015]

According to the present invention, in a paging processing method in a virtual storage system, pages to be accessed when a program is executed are written in an access page history table. When the same program is executed again, the execution page storage unit selects programs from the unexecuted page storage unit up to the size of the page that can be stored in the execution page storage unit in the order of the pages stored in the access page history table. I do. If a page fault occurs during the execution of a program, the program of pages other than the pages that can be stored in the execution page storage unit from the next used page in the access page history table is paged out to the unexecuted page storage unit. Thereafter, the program of the page requested to be accessed is paged in from pages of a size that can be stored in the execution page storage unit.

[0016]

[0017]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a flowchart showing one embodiment of the operation of the paging processing system of the present invention. FIG. 2 is a block diagram of one embodiment of the paging processing method of the present invention. This paging processing method includes a paging processing control mechanism 1 for controlling paging processing, a main storage device 2 for storing small-scale information, and an auxiliary storage device 3 for storing large-scale information.

The main storage device 2 has an execution page storage unit 21, and the auxiliary storage device 3 has an access page history table storage unit 31 and an unexecuted page storage unit 32.

The execution page storage unit 21 stores programs for pages that can be accessed when executing the program. The access page history table storage unit 31
The history of pages accessed by the executed program is stored for each program. Unexecuted page storage unit 32
Stores a program of a page that cannot be completely stored in the execution page storage unit 21. If a page in this storage unit is accessed during program execution, a page fault occurs and the page is stored in the execution page storage unit 21. Is loaded.

Next, the operation of this embodiment will be described with reference to FIGS.

FIG. 1A is a flowchart showing an interrupt process at the time of page switching. When there are a plurality of pages that can be stored in the execution page storage unit 21, each time the page to be accessed is switched when the program is executed, the address of the page is written to the access page history table storage unit 31 (A1). As a result, the history of the order of pages accessed when one program is executed is recorded. FIG. 1B is a flowchart showing a page load process before executing the program. When a program having a page history is to be executed (B1), the programs up to the size of the execution page storage unit 21 are stored in the non-executed page order in the order of the pages stored in the access page history table storage unit 31. Load from the unit 32 (B2, B3). FIG. 1C is a flowchart showing an interrupt process at the time of a page fault. When an attempt is made to access a page that is not in the execution page storage unit 21 (a page fault has occurred), it is necessary to load the program of the page from the unexecuted page storage unit 32.
Because there is no empty page in the execution page storage unit 21 (C
1) It is necessary to return the program of the unnecessary page to the unexecuted page storage unit 32. This unexecuted page storage unit 3
As a method of selecting the program of the page to be returned to 2, the program from the next page to be accessed in order from the access page history table storage unit 31 to the page of the size of the execution page storage unit 21 is excluded from the target (C
2) Perform page out processing by selecting from other pages (C3). Thereafter, a page-in process is performed on a free area of the execution page storage unit 21 (C4).

As described above, the access page history table storage unit 31 of the execution storage unit 21 excluding the page in which the page fault has occurred is created, and when the program is executed again, the access page history with a small number of page fault occurrences is stored. Speeding up of paging processing by the table storage unit 31 is achieved.

[0024]

[0025]

As described above, in the present invention, the history of the access page of a program is stored, and the page to be paged out is selected based on this history at the time of a page fault, so that the conventional LRU method is used. Has the effect of speeding up paging. In particular, since the page in which the page fault has occurred is excluded from the history of the access page, the speed of the paging process of the program to be executed again can be increased, which is effective for the program development and maintenance in the paging process of the virtual memory.

[Brief description of the drawings]

FIG. 1 is a flowchart of one embodiment of the operation of the paging processing method of the present invention, in which (a) a flowchart showing interrupt processing at the time of page switching, (b) a flowchart showing page loading processing before program execution, and (c). 9 is a flowchart showing an interrupt process at the time of a page fault.

FIG. 2 is a block diagram of an embodiment of a paging processing method according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paging process control mechanism 2 Main storage device 3 Auxiliary storage device 21 Execution page storage unit 31 Access page history table storage unit 32 Unexecuted page storage unit

Claims (4)

(57) [Claims] 1. A paging processing method of the virtual storage system, and recording the order of page history of the accessed program when running one program, sometimes auxiliary storage in attempting to execute the same program again
Pages to be loaded from the main memory in the order of the history.
Selecting a size corresponding to the size of the execution page storage unit; and when a page fault accessing a page stored in the auxiliary storage but not read into the execution page storage unit occurs, the page is used next to the order of the history. A step of excluding a page corresponding to the size of the execution page storage unit in the main storage from the current page, and page-out of other pages and page-in from a page corresponding to the size of the execution page storage unit. The paging method to do. 2. The step of page-in the page, wherein, when a page fault occurs, the page from the next used page in the order of the history to the last page currently stored in the execution page storage unit is deleted. 2. A paging processing method according to claim 1, further comprising the step of page-out of a page portion requested to access by page-out from a page other than. 3. A paging processing method for a virtual storage system.
Oite, programming accessed when executing one program
The order of the ram pages is changed to the first access page history table.
Means to record in the auxiliary memory when the same program is to be executed again.
Pages to be loaded from the main memory in the order of the history.
Means for selecting the size of the row page storage unit, and the execution page storage unit stored in the auxiliary storage,
The page load that accesses the page that is not loaded
When a default occurs, the first access page history table
From the next page used in order from the
Exclude pages of the size of the line page storage section
Page out of pages other than the above and the execution page storage unit
Have a means to page in from a page of size
And a paging processing method. 4. The page-in means for page-in the page,
When a fault occurs, the first access page
From the next page used in the history table order,
Up to the last page currently stored in the line page storage
Leave and page out and access from other pages
Have a means to page in the requested page part
4. The paging processing method according to claim 3, wherein: