JP3339062B2 - Memory area management method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a memory area management method applied to an electrophotographic apparatus or the like.

[0002]

2. Description of the Related Art Conventionally, high speed and high accuracy of an electrophotographic apparatus have been required. The management of the memory area in the electrophotographic apparatus, that is, the acquisition and release of the memory area, the acquisition of a continuous free memory area by packing the used memory area, and the like are performed by the management table. In addition,
This management table stores management data such as the head address, area size, and use status of a memory area managed by the management table.

FIG. 7 shows a conventional memory management method, showing, for example, five management tables 71a to 71e and states of memory areas 72a to 72e managed by the management tables 71a to 71e, respectively.

According to this memory area management method , (1)
The addresses of the memory areas 72a to 72e managed by the management tables 71a to 71e change, respectively. (2) The management tables 71a to 71e are the memory areas 72 stored in the management tables 71a to 71e.
irrespective of the management data types of the memory areas 72a-72e,
They are connected by one chain regardless of the address order of 72e.

[0005]

Therefore, the conventional memory area management method includes (1) the memory areas 72a to 72e.
All management tables 71a are used when acquiring and releasing
(2) When a continuous free memory area is acquired by packing the used memory areas 72a to 72e, all the free memory areas having the minimum address are searched for. Management table 71
Therefore, the memory areas 72a to 7e based on the management tables 71a to 71e must be checked.
There is a problem that the processing time for managing 2e becomes long.

SUMMARY OF THE INVENTION An object of the present invention is to provide a memory area management method for shortening the processing time when managing a memory area by using a management table for the purpose of solving such problems.

[0007]

SUMMARY OF THE INVENTION A memory area management method according to the present invention has the following objects.
As shown in the principle diagram of FIG. 1, the management data of the memory area stored in the management table (1) is connected by the chain (2) in order of the address of the memory area for each management data. I do.

[0008]

According to the memory area management method of the present invention, the management tables (1) for managing the memory areas are arranged in the order of the addresses of the memory areas, and the management table (1) is stored in the management tables (1). Are linked by a chain (2) according to the management data of the memory area.
Therefore, since the respective management data are connected by the same chain (2), the management data of the memory area stored in the required management table (1) can be selected by selecting the required chain (2). The memory area is managed by the management table (1) based on the selected management data.

[0009]

Next, a specific embodiment of a memory area management method according to the present invention will be described with reference to the drawings. FIG. 2 shows a memory area management method according to one embodiment of the present invention.
In the figure, the management table indicated by diagonal lines is in use, and the other management tables are empty.

For example, twelve management tables 21 a to 21 l arranged in the order of addresses in the memory area are sequentially linked to the head chain pointer 23 by the management table chain 22.
Is connected to Note that the final management table 211 is connected to the final chain pointer 24.

The management tables 21a, 21 in the empty state
e and 21i are sequentially connected to the empty chain loop 25. The management table 21e stores the empty search pointer 2
6 and the management tables 21a, 21e, and 21i.
Is checked by the empty search pointer 26.

Management table 2 to which a release instruction has been given
Reference numerals 1f, 21h and 21k are sequentially linked to a release instruction chain pointer 28 by a release instruction chain 27.

The management tables 21m to 21q are unused management tables.
21q are sequentially connected to the empty rcID chain pointer 30 by the empty management table chain 29. Note that r in the empty rcID chain pointer 30
c indicates an area name of the memory area, and ID indicates an identification number.

The management tables 21a-2a as described above
Management data of a memory area managed by the management tables 21a to 21l, that is, a head address, an area size, a page counter value, a general-purpose chain pointer, a back chain pointer, and a chain pointer are stored in each of the 1l (FIG. 3). .

The head address indicates the head address of the memory area managed by the management table, and the area size indicates the size of the memory area. The page counter value is stored in each management table in order to set a number (value) in the memory area in advance and to identify the memory area when releasing the memory area of a predetermined number. The general-purpose chain pointer identifies the acquisition and release of the memory area designated by the management table and the acquisition of a continuous free memory area by packing the memory area in use. The back chain pointer is stored in a management table connected before the management table in which the back chain pointer is stored, that is, in each management table for managing a chain source. The chain pointer is stored in a management table connected after the management table in which the chain pointer is stored, that is, in each management table for managing a chain destination.

Acquisition and release of a memory area by the memory area management method configured as described above, and acquisition of a continuous free memory area by packing a memory area in use are performed as follows. In the figure, the management table indicated by diagonal lines is in use, and the other management tables are empty.

FIG. 4 shows the state of the management table when a memory area is acquired by this memory area management method .
The empty management tables 41a to 41e are sequentially linked to the empty chain loop 25. In the empty chain loop 25, the management tables 41a to 41e are checked by the empty search pointer 26a.

First, if the memory area managed by the management table 41b recognized by the empty search pointer 26a has a required area size, the memory area is acquired, and the management table is acquired from the empty chain loop 25. Remove 41b. On the other hand, if the memory area does not have the required area size, the management table 41c connected to the empty chain loop 25 is checked by the empty search pointer 26b, and the memory area managed by the management table 41c is determined to be the required area. If it has the size, it acquires that memory area.

If the memory area obtained in this way is smaller than the size of the memory area managed by the management table 41c, (((size of memory area managed by management table 41c))-( A free memory area corresponding to the size of the acquired memory area)) is created. To manage this free memory area, a management table 41f is introduced from the free rcID chain pointer 30 and the management table 41f is introduced.
f is linked to the leading chain pointer 23. The obtained memory area is managed by the management table 41c.

FIG. 5 shows the state of the management table when the memory area is released by the above-mentioned memory area management method .
When releasing the memory area, first, as shown in FIG.
If there is a management table 51a corresponding to the release instruction, the memory area managed by the management table 51a is released. As a result, this memory area becomes a free memory area.

If the memory area managed by the management table 51b connected after the management table 51a is in the free memory area, the memory areas in the free memory area exist continuously. The memory areas in the free memory area are integrated, and the integrated memory area is managed by the management table 51a. The management table 51a stores the empty chain loop 25
The remaining management table 51b is connected to the empty rcID chain pointer 30.

In order to obtain a continuous free memory area by packing the used memory area, as shown in FIG. A certain management table 61a is searched. Since the memory area managed by the management table 61a is a free memory area, the memory area managed by the management table 61b that is continuous with the management table 61a is managed by the management table 61a and is a free memory area. Perform the operation to fill the memory area. By repeating such operations, the management table 61c for managing the memory area in the free memory area,
61d, these management tables 61
The memory areas managed by c and 61d are integrated, and the integrated memory area is managed by the management table 61c. The surplus management table 61d has an empty rcID.
It is connected to a chain pointer 30. Thereafter, such an operation is continued up to the final management table.

The management table 21 in the present embodiment
a to 21q, 41a to 41f, 51a, 51b, 61a
61d correspond to the management table (1) in the present invention, and the management table chain 22, the empty chain loop 25, the release instruction chain 27, and the empty management table chain 29 correspond to the chain (2).

[0024]

As described above, according to the present invention, the management of a memory area such as the acquisition and release of a memory area and the acquisition of a continuous free memory area by packing the used memory area by the management table. The processing time when performing the above can be shortened.

[Brief description of the drawings]

FIG. 1 is a principle diagram showing the principle configuration of a memory area management method according to the present invention.

FIG. 2 is a configuration diagram of a memory area management method according to an embodiment of the present invention.

FIG. 3 is a diagram showing management data of a memory area stored in a management table of a memory area management method according to one embodiment of the present invention.

FIG. 4 is a diagram illustrating a state of a management table when a memory area is acquired by a memory area method according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating a state of a management table when a memory area is released according to the memory area management method of one embodiment of the present invention.

FIG. 6 is a diagram for explaining a state of a management table when a continuous free memory area is obtained by filling a used memory area according to the memory area management method according to one embodiment of the present invention; is there.

FIG. 7 is a configuration diagram of a conventional memory area management method .

[Explanation of symbols]

1, 21a to 21q, 41a to 41f, 51a, 51
b, 61a to 61d management table 2 chain 22 management table chain 25 empty chain loop 27 release instruction chain 29 empty management table chain

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-58-171780 (JP, A) JP-A-1-185747 (JP, A) JP-A-3-44747 (JP, A) JP-A-3- 189842 (JP, A) JP-A-3-245234 (JP, A) JP-A-63-39055 (JP, A) Dynamic storage area allocation method, Masataka Sasa, Japan, Information Processing, April 15, 1983 , Vol. 24, No. 4, p. 408-412 (58) Field surveyed (Int.Cl. ⁷ , DB name) G06F 9/46 G06F 12/00-12/02

Claims (1)

(57) [Claims] 1. An area of a memory used in an electrophotographic apparatus.
Memo to manage the management table for managing the
When connecting with the management table chain in the order of the address of the storage area
First, it corresponds according to the state of each managed memory area.
Each management table for each management data stored in the management table
Release chain, empty chain, empty
Connect to the management table chain and handle unused areas
Linked management tables with an empty management table chain
In the memory area management method and performing the acquisition and release management of the memory area.