JPH01169550A - Buffer control system - Google Patents

Abstract

PURPOSE:To make it possible to use a buffer even when a physical continuous area corresponding to the size of a required buffer does not exist by regarding dotted areas such as a return buffer as a logically continued area. CONSTITUTION:When a buffer request is generated from a certain task, a continuous area checking means 120 checks whether a continuous area corresponding to the size of the requested buffer exists or not by referring a control table 130. When the area exists, a continuous area return means 140 applies a task for the continuous area buffer request to update buffer size information. When the continuous area corresponding to the required size does not exist, a logical buffer return means 150 returns a logical buffer chained by the table 130 from the buffer area 110, changes the contents of relating individual tables 130 to update the total buffer size information to be used by a control table updating means 160.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a management method for managing buffers in a memory of a computer or the like.

[Conventional technology]

In conventional buffer management systems, when a task or the like requests a buffer, it searches for a contiguous area in the physical address space of the requested size and allocates the buffer area to the task.

[Problem that the invention seeks to solve]

In the conventional buffer management method described above, if the area for the requested buffer size is not contiguous, even if the total size of the available buffer area is larger than the requested size! Even if you do, you can only allocate the buffer area.

[Means for solving problems]

The method of the present invention includes a buffer storage means for storing information;
A plurality of management tables provided corresponding to a plurality of usable areas scattered within the buffer storage means and including address information indicating the range of the corresponding area and pointer information indicating the next table; In response to the buffer acquisition request, allocates an area of the size requested by the acquisition request to the request source by referring to the management table, deletes or updates the management table corresponding to the allocated area, and and table changing means for updating the management table or creating a new management table related to the area to be returned in response to a buffer return request from a request source.

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

FIG. 1 shows an embodiment of the present invention, in which (a) shows a portion related to buffer acquisition request processing, and FIG. 1(b) shows a portion related to buffer return request processing.

First, buffer acquisition request processing will be explained with reference to FIG. 1(a). When a buffer request is received from a certain task, the continuous area check means 120 refers to the management table 130 to check whether or not a continuous area corresponding to the requested buffer size exists in the buffer 110. The continuous area acquisition means 140 provides the continuous area buffer to the task that requested the continuous area, and updates the corresponding buffer size information in the management table 130 that manages this continuous area. On the other hand, if a continuous area of the requested size does not exist, the logical buffer return means 150 returns the logical buffers chained by the management table 130 from the buffer area 110, and returns the contents of each related management table 130. change. Then, the management table changing means 160 updates the contents of the main management table, that is, the total usable buffer size information.

Next, the buffer return process will be explained with reference to FIG. When a buffer return request is made from a certain task, the buffer continuation check means 220 refers to the management table 230 to check whether the returned buffer area is contiguous to any of the currently available buffer areas, and If there is an area where the size of the area is, the buffer table changing means 240 updates the size information of the corresponding area in the management table 130. If a continuous area does not exist, the table chain means 250 creates a new management table for the returned buffer area in the management table means 130, and chains it to the chain of management tables that have existed so far.

Finally, the changing means 160 updates the total buffer size information in the main management table.

FIG. 2(a) shows the state of the buffer 110 at a certain point in time, including a plurality of in-use areas and return areas (areas that have been used at least once but are currently unused).
and unused area (area that has never been used)
are scattered. FIG. 4B conceptually shows the contents of the management table means 130 reflecting the state shown in FIG.

FIG. 3(a) shows the contents of the main management table, including a pointer to the first management table, that is, an address, and the total buffer size information indicating the total size of the usable area in the buffer 110. has.

FIG. 3(b) shows the contents of each management table, which includes a pointer or address to the next management table, the start and end addresses of the area managed by this management table, and buffer size information.

In this embodiment, as shown in FIG. 2(b), a table for managing unused buffer areas is first chained to the main management table, and then a table for managing returned buffer areas is chained to the main management table. ing. if,
If the returned buffer area is contiguous with a currently available buffer area, the size information in the management table of this available buffer area is updated to the size information increased by the returned area. ,
A new management table will not be created for this return area. As a result, the number of management tables can be minimized.

Also, if there is an available buffer area that satisfies the requested buffer size among the chained buffer areas, that buffer will be used preferentially so that buffers in contiguous areas can be used as much as possible. Make it.

〔Effect of the invention〕

As described above, in the present invention, even scattered areas such as return buffers can be viewed as logically continuous areas.
Buffers can be used even if there is no physically contiguous area for the size of the requested buffer. Therefore, the buffer area can be used efficiently.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing the relationship between the buffer status and a management table, and FIG. 3 is a diagram showing the contents of the management table. 110...Buffer area, 120...
・Continuous area check means, 130... Management table means, 140... Continuous area return means, 150... Logical buffer return means, 1
60... Management table changing means, 250...
... table chain means. Agent Patent Attorney Susumu Uchihara /10 /iyu 4
Ushio (A) Main a management tape Ru ryo solid achi) glossy fu-7 hun

Claims (1)

[Scope of Claims] Buffer storage means for storing information; and address information and a following table provided corresponding to a plurality of usable areas scattered within the buffer storage means and indicating the range of each corresponding area. a plurality of management tables containing pointer information indicating a buffer acquisition request from a request source; and in response to a buffer acquisition request from a request source, allocate an area of the size requested by the acquisition request to the request source by referring to the management table; A table change that deletes or updates a management table corresponding to the area that has been returned, and updates the management table or creates a new management table related to the area to be returned in response to a buffer return request from the request source. A buffer management method comprising means.