JPS6358557A - Control system for dynamic memory area - Google Patents

Abstract

PURPOSE:To perform the security/release processing at a high speed even in case the security/release processing has high frequency against to the memory areas of different sizes, by using a correspondence type area control table and a mixture type are control table together with a free chain. CONSTITUTION:The pointers to the unused areas in a main memory area are sorted by their sizes and stored in an area size correspondence type area control table 1. While an area size mixture type area control table 2 stores said pointers unsorted. A free chain 3 chains the unused areas in the order of addresses excluding those unused areas registered in the table 1 or 2 in the main memory area. A memory area security processing means of a computer system retrieves the input memory areas having different sizes in the priority order of both tables 1 and 2 and the chain 3 to secure these memory areas. A memory area release processing means registers the memory areas indicated by the input pointers in the priority order of both tables 1 and 2 and the chain 3 and releases these memory areas.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dynamic storage area management system, and in particular to a dynamic storage system for dynamically securing and releasing storage areas in a computer system. Regarding area management methods.

[Conventional technology]

Conventionally, in this type of dynamic storage area management system, dynamic storage area allocation and release processing is performed using unused records 9 in segment 4, which is one space in the main storage, as shown in FIG. ? It is common to use a free chain 3 in which +Jll area 5 is inherited in the order of addresses in segment 4.

In such a dynamic storage area management system using the free chain 3, as shown in FIG. 5, the tα area 5 has control information usually consisting of two words at the beginning thereof. The first word of this control information stores a pointer to the next element of free chain 3 when storage area 5 becomes a component of free chain 3, and the second word stores the area size of storage area 5. is stored.

The process of securing the storage area 5 is to use numerical data indicating the area size of the storage area 5 to be secured as manual data, and to obtain the storage area 5 having the area size indicated by this numerical value.
This is a process of outputting a pointer indicating the location of this storage area 5. In this example of the reservation process for the area 5, the free chain 3 is first searched in order from the first storage area 5, and a storage area 5 having a size equal to or larger than the area size to be secured is found. If there is a partial area larger than the area size that should be secured in the discovered storage area 5, then write 4. Then, it outputs a pointer to the storage area of the area size to be secured, and leaves the storage area of the remaining area size in free chain 3.
If there is no partial area larger than the area size to be secured in the discovered storage area 5, a pointer to this storage area 5 is output, this storage area 5 is deleted from the free chain 3, and the free chain 3 is Perform the reconfiguration process.

The process of releasing the storage area 5 is a process in which a pointer to the storage area 5 to be released is manually set, and the storage area 5 pointed to by this pointer is made reusable as an unused area. In an example of the process of releasing the storage area 5, first, the free chain 3 is searched in order from the first storage area 5, and components of two adjacent free chains 3 sandwiching the address of the storage area 5 to be released are found. If the storage area 5 to be released is a small number of the two components before and after (both are contiguous with one, then connect them to avoid fragmentation of the storage area 5, and if they are not contiguous, the memory to be released is Processing is performed to reconstruct the free chain 3 by using the region 5 as a constituent element of the free chain 3.

Note that in language processing systems that allow the user to perform pointer operations, it is checked whether the input pointer to the storage area 5 to be released actually points to the beginning of the allocated storage area 5. The allocation in which the storage area 5, which is secured for this purpose, is connected to the chain has a chain, and when performing release processing, this allocation first checks the validity of the manually created pointer by searching the chain. There are many things. In this case, in order to avoid the overhead caused by searching the chain twice, there is an example in which the chains are unified by determining unused areas and reserved storage areas by tags.

By the way, when the reservation processing and release processing of the 1i2eJI area 5 are dynamically performed, the following two cases usually occur when looking at the area size of the storage area 5 that is the target of the reservation processing and release processing. Win 8 yen for any of the following.

11) A case where a relatively large storage area 5 is secured and the securing process and release process do not occur much.

(2) -Although a large storage area 5 is not secured at each time,
A case where securing processing and releasing processing for storage areas 5 of various sizes occur frequently, and securing processing and releasing processing for storage areas 5 of several different sizes occur frequently.

[Problem that the invention seeks to solve]

The conventional dynamic storage management method described above uses free chains to search for storage areas, so chains are often searched for both storage area allocation and release processing. The drawback is that the process of allocating and releasing memory space is slow.
The above disadvantages become even more pronounced as the length of the chain increases.

An object of the present invention is to provide an operation system that enables high-speed storage area allocation and release processing even when storage areas of multiple sizes are frequently allocated and released. The objective is to provide a storage area management method for

[Means for solving problems]

The dynamic storage area management method of the present invention includes an area size-aware area management table that stores pointers to unused areas in the main storage area classified by area size of the unused area; an area size mixed type area management table that stores pointers to unused areas without classifying them according to the area size of the unused area; the area size corresponding type area management table in the main storage area; and the area size mixed type area in the main storage area. A free chain in which unused areas other than unused areas registered in any of the management tables are chained in the order of addresses, and a storage area having the input area size are stored in the area size-based area management table and the area. a storage area release processing means for reserving a storage area by searching based on the size mixed area management table and the priority order of the free chain; and the area size corresponding type area management table, The storage area release processing means registers the area size mixed area management table and the free chain priority and releases the storage area.

[Effect]

In the dynamic storage area management method of the present invention, an area size-aware area management table stores pointers to unused areas in the main storage area classified by area size of the unused area, and area size mixed area management A table stores a pointer to an unused area in the main storage area without classifying it by the area size of the unused area,
The free chain concatenates unused areas in the main storage area, excluding unused areas registered in either the area size-based area management table or the area size mixed area management table, in the order of addresses, and secures the storage area. A means searches for a storage area in which the input area size exists using an area size compatible area management table, an area size mixed area management table, and free chain priority, secures a storage area, and releases a storage area. The storage area pointed to by the manually entered pointer is registered in the area size corresponding type area management table, area size mixed type area management table, and free chain priority, and the storage area is released.

〔Example〕

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

FIG. 1 is a configuration diagram showing an embodiment of the present invention. The dynamic storage area management method of this embodiment is based on an area size-based area management table (hereinafter referred to as "write") in which pointers to unused areas in segment 4 of the main storage device are classified and registered according to the area size of the unused area. (referred to as a compatible area management table) 1 and a pointer to an unused area in segment 4 is not classified by the area size of the unused area, but registers a pointer to an unused area of any area size. an area size mixed area management table (hereinafter simply referred to as a mixed area management table) 2;
From free chain 3, which is a chain of unused areas in segment 4 excluding unused areas registered in either corresponding type area management table 1 or mixed type area management table 2, the main part is It is configured.

The compatible area management table 1 is a table for registering a plurality of unused areas of multiple types of area sizes in which the process of securing and releasing the storage area 5 frequently occurs.
It is composed of a two-dimensional array of (positive integer)×N (positive integer). Each column of the corresponding area management table 1 corresponds to the area size of the storage area 5 that is subject to reservation processing and release processing, and the area size of the storage area 5 increases in the order in which the columns are counted. Pointers to unused areas of the same area size are stored in order in each row of Corresponding Area Management Table 1, except for the first row, and the first row stores pointers to unused areas within a column. Stores the number of elements that are displayed.

The mixed type area management table 2 is a table for supporting the corresponding type area management table 1, and is composed of a two-dimensional array of K (positive integer) x 2. The first column of the mixed area management table 2 stores pointers to unused areas in order except for the first row, and the first row contains elements that store pointers to unused areas within the column. The number of items is stored. Each row of the mixed area management table 2 except for the first row of the second column stores the area size of the storage area 5 pointed to by the pointer to the unused area that is the element of the corresponding row of the first column. has been done.

Free chain 3 is a chain of unused areas in segment 4 that is not registered in corresponding type area management table 1 and mixed type area management table 2 in the order of addresses. It has the same structure as the free chain 3 in the conventional dynamic storage area management system shown in the figure.

Referring to FIG. 2, the storage area securing process in the dynamic storage area management method of this embodiment includes an area size input step 21, a corresponding area management table search step 22, and a corresponding area management table update step 23. , mixed type area management table search step 24, and mixed type area management table update step 25
, a free chain search and corresponding area management table registration step 26 , and a storage area pointer output step 27 .

Referring to FIG. 3, the storage area release process in the dynamic storage area management method of this embodiment includes the storage area pointer manual step 31 and the corresponding area management table registration determination step 3.
2, a corresponding area management table update step 33, a mixed area management table registration determination step 34, a mixed area management table update step 35, and a free chain storage step 36.

Next, the operation of the dynamic storage area management system of this embodiment configured as described above will be explained.

(11 Storage area securing process In the storage area 5 securing process, first the storage area 5 to be secured is
The area size n (positive integer) of is input (step 21
).

Next, it is searched whether the unused area of the input area size n is registered in the compatible area management table 1 (step 22). , and if the registered number m of pointers to the unused area indicated by the first row in that column is not O, then the registered number m stored in the first row of that column is deleted by one and the corresponding area is created. The management table 1 is updated (step 23), a pointer to the storage area 5 stored in the m-th row of that column is output, and the reservation processing is ended (step 27).

When there is no column corresponding to the area size n to be secured in the compatible area management table 1, or when there is a corresponding column but the number of registered items is O
If so, it is searched whether or not an unused area of size n or more to be secured is registered in the mixed type area management table 2 (step 24). If the number k of registered pointers to the unused area indicated by the first row of the first column of 2 is not 0, the second pointer of the second column
Starting from the row, a size comparison is made with the area size n to be secured, and this is repeated until an area size greater than or equal to the area size n to be secured is found, or until the number of comparisons is reached.

t1 An unused area with an area size l (positive integer) greater than or equal to the area size n to be kept is registered, and the difference (j!-n)
If an area portion having an area size of
- n) description t'l Si area and outputs a pointer to an unused area of area size n to be secured, and the storage area of the remaining area size B - n) is the storage area described later. Performs release processing.

If an unused area with an area size i that is greater than or equal to the area size n to be secured is registered, and the area portion with the difference (1-n) in area size is not subject to allocation processing and release processing, this storage The contents of the first row are transferred to the row where the pointer pointing to area 5 was stored, and the registered number k stored in the first row of the first column is deleted by one to update the mixed type area management table 25. Step 25), a pointer to the stored storage area 5 is output, and the securing process is ended (Step 27).

If an unused area that satisfies the area size n to be secured is not registered in either the compatible area management table 1 or the mixed area management table 2, the free chain 3 is searched (
Step 26). Specifically, it is checked whether the storage area 5, which is each component of the free chain 3, is larger than or equal to the area size n that should be secured based on the area size stored in the second word from the beginning. . At this time, it is also determined whether there is a column corresponding to the area size of the unused area in the corresponding area management table 1, and if there is a corresponding column, it is stored in the first row in that column. On the condition that the registered number m is less than M, the storage area 5
is deleted from free chain 3, and the (m+1)th
A pointer to the tα area 5 is stored in the row, and 1 is added to the registration number m in the first row of the column to update the corresponding area management table 1 (step 26). If there is no corresponding column in the corresponding area management table 1, or if there is a corresponding column but M unused areas have already been registered, the pointer to the corresponding area management table 1 is not registered. do not have.

While checking whether the area size to be secured for the tfj j JI area 5, which is a component of the free chain 3, is greater than or equal to n, checking the registration in the corresponding area management table 1, and performing the registration process, the area is secured. When a storage area 5 with the desired area size n or more is searched, the searched record + 'L'
A pointer to pH range 5 is output and the securing process is completed (step 27).

(2) Storage Area Release Process In the storage area 5 release process, first a pointer to the data area 5 to be released is input (step 31). Then, the second point from the beginning of the storage area 5 pointed to by the input pointer is
The area size n of the storage area 5 is obtained by the word.

Next, it is determined whether the storage area 5 pointed to by the input pointer can be registered in the corresponding area management table 1 (step 32). If there is a column and the number m of registrations indicated by the first row in that column is less than M, a pointer to the storage area 5 to be released is stored in the (m+1)th row in that column, and the Add one to the registered number m of the first row in the column, update the corresponding area management table 1, and end the release process (
Step 33).

If there is no column corresponding to the area size n in the corresponding area management table 1, or if there is a corresponding column but M unused areas have already been registered, the following (t'piJI area 5 is Determine whether it can be registered in the mixed-type area management table 2 (step 34). Specifically, the number k of registrations in the mixed-type area management table 2 is determined from the first row of the first column, and the number k of registrations is determined from the first row of the first column.
If it is less than k, the number (k
+1) Store the pointer to the storage area 5 to be released in the row, store the area size n of the tα area 5 in the (+1) row of the second column, and store it in the first row of the first column. The mixed area management table 2 is updated by adding 1 to the registered number k, and the release process is completed (step 35).

If it cannot be registered in either the corresponding type area management table 1 or the mixed type area management table 2, free chain 3 is searched, and the tq area 5 pointed to by the pointer is added to free chain 3 and released. The process ends (step 36).

〔Effect of the invention〕

As explained above, the present invention uses a corresponding type area management table, a mixed type area management table, and a free chain in combination, so that a large storage area is not secured at each time, but storage areas of various sizes can be created. This has the effect of speeding up the process of securing and releasing the tq area when there are many securing and releasing processes for storage areas of several different sizes.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing storage area securing processing in the dynamic storage area management method of this embodiment, and FIG. 3 is a dynamic storage area diagram of this embodiment. A flowchart showing the storage area release process in the area management method, FIG. 4 is a configuration diagram showing the conventional dynamic storage area management method, and FIG. 5 is a diagram showing the configuration of the storage area that is a component of the free chain. . In the figure, 1... Corresponding type area management table, 2... Mixed type area management table, 3... Free chain, 4... Segment, 5... Written i! area, 21...area size input step, 22...corresponding area management: p, search step, 23.
... Compatible area management table update step, 24... Mixed area management table search step, 25... Mixed area management table update step, 26... Free chain search and compatible area management table registration step, 27...Storage area pointer output step, 31...
Storage area pointer input step, 32... Compatible type area management table registration determination step, 33... Corresponding type area management table update step, 34... Mixed type area management table registration determination step, 35... Mixed type Area management table update step, 3
6... Free chain storage step.

Claims (1)

[Scope of Claims] An area size-aware area management table that stores pointers to unused areas in a main storage area classified by area size of the unused areas; an area size mixed type area management table that stores pointers without classifying them by area size of an unused area, and either the area size compatible type area management table or the area size mixed type area management table in the main storage area. A free chain in which unused areas excluding unused areas registered in are chained in the order of addresses, and a storage area having the input area size in the area size compatible area management table and the area size mixed area management table. a storage area securing processing means for reserving a storage area by searching based on the priority order of the table and the free chain; A dynamic storage area management method comprising: a management table and a storage area release processing means for registering and releasing a storage area in accordance with the priority order of the free chain.