JPS6391754A - Memory size control system - Google Patents

Abstract

PURPOSE:To attain the continuation of the execution of a program, and to reduce overhead, by predicting the ratio of the quantity in use of a memory in each area, to the whole quantities in use of the memory, and re-arranging the memory based on a predicted result. CONSTITUTION:A memory quantity in use detecting means 2 detects the quantity in use in every divided area, and the whole quantities in use of the memory. A ratio calculating means 3 calculates the ratio of an individual quantity in use in each area to the whole quantities in use, and a ratio predicting means 4 calculates a new prediction ratio for each area by using a past prediction ratio 5, and the ratio calculated by the ratio calculating means 3. The prediction ratio 5 is updated at every calculation of the prediction ratio by the ratio predicting means 4. A memory re-arranging means 6 performs the re-arrangement of the divided area of a memory 1, by using a calculated prediction ratio. Therefore, the optimum re-arrangement of a memory area can be performed, and memory resources can be used efficiently.

Description

[Detailed Description of the Invention] [Summary] In an information processing device that divides and stores multiple memory areas with different usage purposes and usage patterns in the same memory, when the usage amount of each area is unknown, the memory of each area is By predicting the ratio of usage to total memory usage and reallocating memory based on the prediction results, it is possible to continue program execution and reduce overhead.

[Industrial application field]

The present invention relates to a memory size control method in an information processing device, and particularly to a distribution control method for each region when a memory is divided into a plurality of different regions for use.

[Conventional technology]

According to conventional information processing devices that use memory by dividing it into memory areas according to usage purposes and usage patterns, the size of each memory area can be determined in advance by executing a program and determining the required memory size. The method used was to measure and determine the

Another conventional method is to determine the amount of memory required for each memory area by prediction.

The prediction attempts to predict the absolute amount of memory required.

[Problems with conventional technology]

Among the conventional techniques, the method of measuring memory size requires a great deal of effort to run the program in advance, and this method is effective in cases where measurement is difficult or where the program is frequently modified. The drawback was that it could not be done. Also.

Other conventional methods for estimating the absolute amount of memory are difficult to predict when the memory is forcibly repartitioned during program execution (when the allocated memory size is all used, or when the memory area is (when a garbage collector instruction appears that redistributes the memory), if the amount of memory used is small, each area will be predicted at a stage where the absolute amount is small, which will affect the prediction results based on the amount used and cause prediction errors. There was a downside to getting bigger.

[Means for Solving the Problems] The present invention also solves forced memory reallocation by predicting the ratio of the memory usage of each memory area to the total memory usage. , it is possible to obtain stable prediction results.

FIG. 1 shows the basic configuration of the present invention.

In FIG.

(2) is a memory that is used by dividing the area according to usage.

Reference numeral 2 denotes a memory usage amount detection means for detecting the memory usage amount for each divided area (individual usage amount) and the entire memory usage amount (total usage amount).

3 is a ratio calculation means for calculating the ratio of the individual usage amount of each area to the total usage amount.

4 is a ratio prediction means that calculates a new prediction ratio for each region using the past prediction ratio 5 and the ratio calculated by the ratio calculation means 3. Various known methods can be used as the prediction method.

5 is a past predicted ratio that is updated every time the ratio prediction means 4 calculates a predicted ratio.

Reference numeral 6 denotes a memory redistribution means that redistributes the divided areas of the memory 1 using the calculated prediction ratio.

[Effect]

According to the present invention, the usage status of each divided memory area is monitored at appropriate timing, and the size of each divided area is dynamically readjusted according to the actual memory usage. Optimal allocation of areas is performed, and memory resources are made more efficient.

〔Example〕

FIG. 2 is a diagram showing the configuration of one embodiment of the present invention.

11 is a memory, 12 is a memory size register, 13 is a memory usage register, 14 is a total memory usage counting circuit, 15 is a usage ratio calculation circuit, 16 is a predicted value holding circuit, 17 is a usage ratio prediction circuit, 18 represents a memory redistribution circuit, and 19 represents a data movement circuit.

In the example shown in this figure, the memory 11 has three areas A.

It is divided into B and C, and the memory is shown to be used up to the shaded area. Boundary addresses representing the set memory sizes of each memory area A to C are held in the memory size register 12.

The memory usage register 13 shows how far each area A to C is used.

When a garbage collector (not shown) is activated, for example, depending on which of the areas A-C of the memory becomes full, the boundary address of each area held in the memory size register 12 and the memory usage are quantity register 1
The memory usage amount counting circuit 14 calculates the difference between the memory usage amount (address) of each area shown in 3 to obtain the memory usage amount of each area, calculates their sum, and calculates the result as the usage ratio. It is output to the calculation circuit 15.

In the usage ratio calculation circuit 15, the total memory usage counting circuit 1
4, the usage of each memory area is determined from the difference between the memory size register 12 and the memory usage register 13, and each usage is expressed as the total memory usage which is the output of the total memory usage counting circuit 14. By dividing, the usage ratio of each memory area is calculated.

The current usage ratio of each memory area, which is the result of this calculation, is supplied to the usage ratio prediction circuit 17, which performs predictive calculation using the value of the predicted value holding circuit 16 that holds the predicted value of the previous usage ratio.

As an example of the prediction method in the usage ratio prediction circuit 17, when employing the exponential smoothing method, the previous predicted value stored in the predicted value holding circuit 16 is S l j −1 (0≦S 1
j-1≦1), and the current actual value of the memory use ratio obtained by the use ratio calculation circuit 15 is Ui, (0≦Uth≦1)
, the smoothing index is α (0 < α × 1), and the current predicted value is 5l
Let j (0≦S, J≦1).

S, J=α・U4. + (1-α) ・5lj-1
Further, the subscript i indicates the number of the memory area, and the subscript j indicates the number of predictions.

In the usage ratio prediction circuit 17, α, 1−α.

The current usage ratio prediction value is obtained based on the previous prediction value S1j-1 of the prediction value holding circuit 16 and the current usage ratio of each memory area from the usage ratio calculation circuit 15.

The value is set in the predicted value holding circuit 16 and output to the memory redistribution circuit 18.

The memory redistribution circuit 18 redistributes the entire memory based on the usage ratio of each area of the memory.

Specifically, let the overall memory size be M and the memory size of each area be HlJ.

HH=M-3Hj becomes.

When the memory redistribution circuit 18 calculates the memory size of each memory area, it obtains the boundary address corresponding to the size, outputs the value to the memory size register 12 and the memory usage register 13, and sets them respectively. , are used to specify the memory size and the address corresponding to the usage amount, respectively.

At the same time, the output of the memory redistribution circuit 18 is supplied to the data movement circuit 19, and in this circuit 19, the outputs of the previous memory size register 12 and memory usage register 13 and the current output from the memory redistribution circuit 18 are According to the new boundary address, control is executed to move data in each memory area to a corresponding address, thereby performing memory redistribution.

〔Effect of the invention〕

According to the present invention, by predicting the usage amount of each area of memory divided into multiple areas according to the purpose of use and usage type using the usage ratio, it is possible to stably obtain memory partitioning that is optimal for a program. It is possible to suppress the difficulty of program execution and increase in overhead associated with this, and it is possible to effectively improve the performance of the computer.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the basic configuration of the present invention, and FIG. 2 is a diagram showing the configuration of one embodiment of the present invention. 1 in Figure 1: Memory 2: Memory usage detection means 3: Ratio calculation means 4: Ratio prediction means 5: Past predicted ratio 6: Memory reallocation means

Claims (1)

[Claims] In an information processing device that divides the same memory (1) into a plurality of memory areas for different uses, there is provided a memory usage detection means (2) for detecting the memory usage of each area, and the memory usage of each area. a ratio calculation means (3) for calculating the ratio of the total memory usage of
4) and memory redistribution means (6) for redistributing memory according to the predicted ratio of each area, predicting the usage ratio of each area in response to a request for memory redistribution, and responding to the result. A memory size control method characterized by reallocating memory.