KR19990019417A - Memory Management - Google Patents

Abstract

After storing information about the size of the plurality of fragmented usable areas, detecting the size of the task to which the memory allocation request has been received, the size of the at least one usable area having a size greater than or equal to the size of the task is the closest to the size of the task. Allocates the available area of the file first.

Therefore, efficient management of the memory is possible.

Description

Memory Management

The present invention relates to a memory management method, and more particularly, in all electrical and electronic devices using a memory, such as a computer, a multifunction printer, a printer, and the like, when new data is allocated to a fragmented usable area of the memory. The present invention relates to a memory management method of improving memory usage efficiency by allocating a memory area of a size closest to a size first.

In the conventional case, the memory management apparatus always allocates memory in the same way for memory requests. That is, regardless of the size of the requested memory block, the area is allocated as much as the size of the requested memory from the front or rear of the available area.

Subsequently, when a predetermined size of an available area of the memory is allocated to perform a task and then terminated, the previous task occupied in the memory is released to perform the next task. You must do it. Thus, some of each allocation area is converted into usable area, whereby the usable area does not exist as one large area but as a plurality of fragmented areas. If this process is repeated many times, the usable area is fragmented into a very small sized area.

Thereafter, when a memory allocation request is received to perform the next task, the memory management apparatus allocates to the corresponding task according to its position regardless of its size for a plurality of fragmented available areas.

However, this conventional memory management method causes the following problems.

(1) When a memory allocation request is received, the memory management device allocates memory according to its position among a plurality of fragmented usable areas. Therefore, if there are more fragments of the usable area by repeating countless allocations and releases, the memory area that is actually left remains. In many cases, if there is no free space larger than the size of the memory allocation required to perform the task, memory allocation may fail in response to the memory allocation request.

(2) As the fragmented area of the memory increases, the memory is operated inefficiently.

Accordingly, an object of the present invention is to solve such problems, and a first object of the present invention is to manage information about the size of a fragmented usable area of a total memory, and when a memory allocation request for performing an arbitrary task is received. The present invention provides a memory management method for detecting an available area having a size closest to a task size and allocating the available area.

In addition, a second object of the present invention is to provide a memory management method for efficiently managing a memory in accordance with the first object.

1 is a schematic block diagram of a memory management apparatus applied to the present invention;

2 is an operation flowchart showing a process of performing a memory management method according to the present invention;

3A to 3C are memory structure diagrams illustrating a state in which a memory is managed by each step shown in FIG.

* Explanation of symbols for main parts of the drawings

1: memory management unit 2: memory initialization unit

3: memory allocation unit 4: memory release unit

5: information storage

Features of the present invention for achieving the above object, the initialization step of partitioning the system area and the variable area and the usable area when the system is initialized; A first detecting step of detecting a size of a task requested to be allocated when a memory allocation request is received; A second detecting step of detecting a size of the usable area stored according to an arbitrary condition; Allocating an available area having a size closest to the size of the task; And an updating step of updating information on the size of the available area for the allocated available area, wherein the memory management method is repeated from the first detection step to the update step until the system is turned off. have.

Preferably, the second detection step stores the usable area in order of decreasing size.

Preferably, the allocating step allocates a usable area of a size closest to the size of the task among usable areas having a size greater than or equal to the size of the task.

Optionally, when the memory release request is received, the release step of releasing the area; And setting the released corresponding region as a new usable region and updating information on the size of the new usable region.

Hereinafter, a preferred embodiment of the memory management method according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic block diagram of a memory management apparatus applied to the present invention.

As shown in FIG. 1, the memory management apparatus 1 according to the present invention is roughly divided into a memory initialization unit 2, a memory allocation unit 3, a memory release unit 4, and an information storage unit 5. do. That is, the present invention further includes an information storage unit 5 in the configuration of a general memory management apparatus including the memory initialization unit 2, the memory allocation unit 3, and the memory release unit 4.

An operation of the present invention having such a configuration will be described below with reference to FIGS. 2 and 3.

In electrical and electronic devices such as computers, printers, and multifunction devices, efficient management of the memory is a major factor in determining the performance of the system. During the execution of the system, the memory is repeatedly allocated and released.

At this time, since the allocation and repetition of the memory are not performed sequentially, the memory that initially contained the huge usable area is divided into a plurality of areas, and a small area among the plurality of divided areas is suitable for the area. If you do not receive it, you may not be able to use it forever.

Typically, memory is managed in basic units (sizes), which are 16 bytes, 32 bytes, 64 bytes... … And the like.

When the system is initialized (S1), as shown in FIG. 3A, the memory initialization unit 2 in the memory management apparatus 1 may convert a partial area of the entire area of the memory into a system area and a variable area. ) And initialize the memory by allocating the remaining area to the available area (S2). In addition, the information storage unit 5 is initialized (S3) and stores that only one huge usable area exists in the memory.

Then, in order to perform any task, when a memory allocation request is received (S4), the memory management apparatus 1 detects the size of the allocation requested area (S5), and is available through the information storage unit 5. The area is searched sequentially from the small area (S6). At this time, since only one usable area exists in the memory when the memory is initialized, only one usable area is searched in step 6 (S6).

If the size of the usable area is equal to or larger than the size of the allocated area, the memory allocating unit 3 allocates the available area (S8) and updates the storage contents of the information storage unit 5 (S9). When the memory is allocated to a plurality of tasks by repeating the above process, as shown in FIG. 3B, an available area and a plurality of allocated areas exist. Then, it is determined whether the system is off (S10). If the system is off, all the processing ends. If the system is not off, the process returns to step 4 (S4).

On the other hand, if the memory allocation request is not received in step 4 (S4), it is determined whether the memory release request is received (S11), and if the memory release request is received, the memory release unit 4 releases the corresponding area (S12). ). Accordingly, the memory has a plurality of fragmented usable regions as shown in FIG. 3C.

At this time, the size of the pieces of the usable area are all different depending on the size of the task used. The information about the size of the usable area is sequentially stored in the information storage unit 5. In this case, the information storage unit 5 arranges and stores the size of the usable area in a small order.

Subsequently, when the memory allocation request is received in step 4 (S4), the size of the task and the size of the available area stored in the information storage unit 5 are compared with each other to determine an available area having a size closest to the size of the task. Assign.

For example, as shown in FIG. 3C, when the size of the fragmented usable area is 100 blocks, 50 blocks, 10 blocks, or 100 blocks, the information storage unit 10 has 10 blocks → 50 blocks → 100 blocks → 100. When the size of the task is 70 blocks, the memory management apparatus 1 stores the smallest size information 10 among the information on the usable area stored in the information storage unit 5. Block) and compare it with the size of the task. At this time, since the size of the available area (10 blocks) is smaller than the size of the task (70 blocks), the memory management apparatus 1 determines the size of the next available area (50 blocks, 100 blocks) and the size of the task ( 70 blocks) are sequentially compared, and finally, the memory allocation unit 3 allocates an available area having a size of 100 blocks to the corresponding task.

Therefore, the most efficient memory management is possible by first allocating an available area of the size closest to the size of the task.

As a result, according to the memory management method of the present invention, memory management can be efficiently performed by first allocating an available area having a size closest to the size of the task.

Claims (4)

An initialization step of dividing and setting the system area, the variable area, and the usable area when the system is initialized; A first detecting step of detecting a size of a task requested to be allocated when a memory allocation request is received; A second detecting step of detecting a size of the usable area stored according to an arbitrary condition; Allocating an available area having a size closest to the size of the task; And And an update step of updating information on the size of the usable area for the allocated usable area, repeating from the first detection step to the update step until the system is turned off. The method of claim 1, wherein the second detection step, And a memory management method in which the size of the available area is stored in order of decreasing size. The method of claim 1, wherein the assigning step, And allocating an available area having a size closest to the size of the task among the available areas having a size greater than or equal to the size of the task. The method of claim 1, A release step of releasing a corresponding area when a memory release request is received; And And setting the released corresponding area as a new usable area, and updating the information on the size of the new usable area.