JPH0216652A - Missing page processing system - Google Patents

Abstract

PURPOSE:To execute a program without interrupting the process when a missing page occurs and to shorten processing time by restarting the execution of the program without waiting for the completion of page loading from a secondary memory device when the missing page occurs due to writing. CONSTITUTION:In receiving the notice of occurrence of a missing page from a missing page notifying means 1, a write/readout deciding means 2 decides whether the missing page occurs due to reading out or writing and, when the missing page occurs due to writing, the means 2 calls a pseudo writing means 3. When the entry of the address of the missing page is already registered in a pseudo writing management table 4, the means 3 updates the written content of the entry. When the entry is not registered, the means 3 prepares a new entry and registers the writing content. Thereafter, the means 3 causes the execution of a program to be restarted by actuating a real page loading means 5 and returning the control to the program stored in a main memory.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a missing page processing method, and particularly to a missing page processing method in a virtual memory computer system.

[Conventional technology]

As is well known, when a program is executed on a virtual memory computer system, a missing page occurs, but when a missing page occurs, program processing cannot be continued, so program execution is temporarily interrupted. Then, the address of the missing page is found, and the missing page notification means notifies the occurrence of the missing page.

In the conventional missing page processing method, when receiving a notification of the occurrence of a missing page from the missing page notification means, the page that becomes the missing page is loaded from the secondary storage device to the main memory, and a missing page is generated after the loading is completed. Resumes execution of the program that was previously deleted.

[iJ problem that the invention seeks to solve]

In the conventional missing page processing method described above, the page is saved on the secondary storage device, then loaded onto the main memory, and the program is restarted after waiting for page loading to complete. Aborts the program whenever it occurs.

The drawback is that page loading and program restart occur, increasing the load on the central processing unit and reducing the program execution speed.

Furthermore, in order to prevent missing pages, many pages may be allocated to the main memory, but in this case there is a drawback that the main memory becomes overwhelmed.

In view of the above points, an object of the present invention is to provide a missing page processing method that allows processing to be continued without interrupting the program when the missing page is generated by writing. .

[Means to solve the problem]

The missing page processing method of the present invention is provided in a virtual memory computer system having a missing page notification means for notifying a page address where a missing page has occurred.
write/read determination means for determining whether the missing page notified by the missing page notification means is generated by writing or reading; and the write/read determination means determines that the missing page is generated by writing. A pseudo write execution means for pseudo writing when a determination is made; a pseudo write management table for storing pseudo writes that are the execution results of the pseudo write execution means; and a missing page generated by reading by the write/read determination means. pseudo write determination means for determining whether or not a pseudo write to the real page after loading is stored in the pseudo write management table when it is determined that the pseudo write has been stored in the pseudo write management table; and pseudo write reflecting means for writing so as to reflect the pseudo write stored in the pseudo write management table in the real page after loading when it is determined that the pseudo write has been performed.

[Effect]

In the missing page processing method of the present invention, the write/read determination means determines whether the missing page notified by the missing page notification means is generated by writing or reading, and the pseudo write execution means determines whether the missing page notified by the missing page notification means is generated by writing or reading. When it is determined that the missing page is caused by a write, the pseudo write is performed, the pseudo write management table stores the pseudo write that is the execution result of the pseudo write execution means, and the pseudo write determination means writes the pseudo write. When the reading determination means determines that the missing page is generated by reading, the pseudo write management table determines whether a pseudo write to the real page after the write is stored, and the pseudo write reflection means When it is determined by the pseudo write determining means that a pseudo write is stored, writing is performed to reflect the pseudo write stored in the pseudo write management table on the real page after loading.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a missing page processing method according to an embodiment of the present invention. The missing page processing method according to the present embodiment includes a missing page notification means 1,
A write/read determination means 2, a pseudo write execution means 3,
It is composed of a pseudo write management table 4, a real page load means 5, a pseudo write determination means 6, and a pseudo write reflection means 7.

Referring to FIG. 2, the pseudo write management table 4 stores page addresses, intra-page addresses, and write contents.
It consists of a table that stores multiple entries as one entry.

Next, the operation of the missing page processing method of this embodiment configured as described above will be explained.

When receiving a notification of the occurrence of a missing page from the missing page notification means 1, the write/read determination means 2 determines whether the missing page is generated by writing or reading.

If it is determined that the missing page has been generated by writing, the write/read determination means 2 calls the pseudo write execution means 3 (hereinafter referred to as write execution means 3).
If the entry for the missing page address (page address and intra-page address) has already been registered in the pseudo write management table 4, the write content of that entry is updated, and the entry is added to the pseudo write management table 4.
If the entry for the address that became the missing page is not registered, a new entry is created and the written content is registered. Thereafter, the pseudo write execution means 3 transfers the missing page from the secondary storage (not shown) to the main storage (not shown) to the real page load means 5.
Requests an upward page load and returns control to the program to resume execution.

On the other hand, if it is determined that the missing page is generated by reading, the write/read determination means 2 calls the real page load means 5. When the completion of loading of the real page is notified, the pseudo write determination means 6 loads the page that became the missing page and waits for its completion. The pseudo write reflection means 7 determines whether or not there is an entry for the page, and calls the pseudo write reflection means 7 if there is an entry. The written content is reflected, and then the corresponding entry in the pseudo write management table 4 is deleted to return to the state where there was no pseudo write. After this, control is returned to the program and execution is resumed. In addition, the pseudo writing determination means 6
If it is determined that there is no entry for the address in the page that has been loaded in the pseudo write management table 4, control is immediately returned to the program and execution is resumed.

〔Effect of the invention〕

As explained above, the present invention restarts program execution without waiting for the page loading from the secondary storage device to be completed when the missing page is generated by writing. , without interrupting processing when a missing page occurs due to writing (
This has the effect of allowing the program to continue running and shortening the program execution time.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a sourcing page processing method according to an embodiment of the present invention, and FIG. 2 is a diagram showing the contents of the pseudo write management table in FIG. 1. In the figure, 1... Missing page notification means, 2... Write/read determination means, 3... Pseudo write execution means, 4... Pseudo write management table, 5... Real page load means, 6. ...Pseudo write determination means; 7.Pseudo write reflection means.

Claims (1)

[Claims] In a virtual memory computer system having a missing page notification means for notifying a page address where a missing page has occurred, the missing page notified by the missing page notification means is generated by writing or reading. a write/read determination means for determining whether the missing page is a missing page; a pseudo write execution means for performing a pseudo write when the write/read determination means determines that the missing page has been generated by writing; a pseudo write management table that stores pseudo writes that are the execution results of the means; and a real page after being loaded into the pseudo write management table when it is determined by the write/read determination means that a missing page is generated by a read. a pseudo write determination means for determining whether a pseudo write is stored in the real page after loading, and a pseudo write determination means for determining whether or not a pseudo write is stored in the real page after loading, when the pseudo write determination means determines that a pseudo write is stored in the pseudo write management table; 1. A missing page processing method comprising pseudo write reflection means for writing so as to reflect a stored pseudo write.