JPH03263142A - Memory managing method - Google Patents

Abstract

PURPOSE:To retrieve the unused block of a memory at a high speed by allowing one block to correspond to one bit and identifying the using state of the block with ON/OFF of its bit. CONSTITUTION:A memory 3 is managed at every a block unit with a block management table 2 and a block using state management table 1. Also, the address management of a block of the memory 3 is executed by the block management table 2, and the management of the using state of the block of the memory 3 is executed by the ON/OFF state of a bit on a table in which the block provided separately from the block management table 2 corresponds to the bit. In such a manner, it does not take time for retrieving the unused block of the memory 3.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a memory management method for a computer system.

[Conventional technology]

In conventional memory management methods, management of block usage status (used/unused) is included in a block management table that manages block addresses, and when searching for an unused block, the block management table is searched. Was.

[Problem to be solved by the invention]

In the conventional memory management method described above, the management of whether a block is in use or not is included in the block management table that manages the address of the block, and when searching for an unused block, the block management table is searched in order from the top. Investigate,
This was done by checking whether a flag indicating whether a block was unused was turned on or off, so if an unused block was located at the end of the block management table, it would take time to search, and as a result, the efficiency of requests for memory allocation would be reduced. It is inevitable that it will decline.

[Means to solve the problem]

The memory management method of the present invention manages memory in units of blocks, manages addresses of the memory blocks using a block management table, and manages usage status of the memory blocks separately from the block management table. This is performed based on the on/off state of the bits on a table in which the blocks correspond to bits.

〔Example〕

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

Referring to Figure 1, which shows the configuration of an embodiment of the present invention,
In this memory management method, the memory 3 is managed in units of blocks using a block management table 2 and a block usage status management table 1.

Here, one block can be any number of bytes. In the block usage management table 1, one bit is allocated for each memory block, and this bit can be turned on (“1”) or off (“1”).
0") allows you to know whether the corresponding block is in use or not. Also, the bit position corresponds to the index of the block management table 2 that manages the start address of the corresponding memory block, and the block usage status The i-th bit of the management table 1 indicates whether the memory block managed by the i-th entry of the block management table 2 is in use or not.

FIG. 2 shows the procedure for securing an unused block in the memory 3 in the same embodiment. First, the block usage status management table 1 is searched (Sl), and the presence or absence of an unused block is determined (S2), i.e. , check whether there is an on bit in the block usage status management table 1. if,
If there are no unused blocks, return error (S3)
Also, if there is an unused block, check the on-pit bit position in the block usage status management table 1 and store it in a register etc. as a block number (S4).
Then, to indicate that the block is in use, turn on the bit position corresponding to the block number in block usage management table 1 (S5), and then turn on the bit position corresponding to the block number in block management table 2. By looking at the entry, the block address of the secured memory block is obtained (S6).

〔Effect of the invention〕

As explained above, according to the present invention, by providing a block usage status management table in which one block corresponds to one bit and the usage status of the block is identified by turning on/off that bit, unused blocks of memory can be saved. Search can be done quickly. Furthermore, since the bit position serves as an index of the block management table that manages block addresses, the corresponding memory block can be accessed quickly.

[Brief explanation of drawings]

FIGS. 1 and 2 are diagrams showing one embodiment of the present invention. 1...Block usage status management table, 2...Block management table, 3...Memory.

Claims (1)

[Claims] A table that manages memory in units of blocks, manages addresses of the memory blocks using a block management table, and manages the usage status of the memory blocks separately from the block management table, in which the blocks correspond to bits. A memory management method characterized in that the above is performed based on the on/off state of the bit.