JPH04123148A - Page allocating system - Google Patents

Abstract

PURPOSE:To execute the setting of a page size being suitable for the memory request amount of a program and the application of a page by setting dynamically the page size in accordance with the memory request amount from the program. CONSTITUTION:A page size determining means 2 receives a memory allocation request from a processing program 1 for executing various processings, extracts the memory request amount add determines a page size, and a virtual space allocating means 3 receives the memory request amount determined by the page size determining means 2, allocates a virtual space, and executes a setting request of a page size of the allocated virtual space and an allocation request of a page. A page size setting means 4 receives the setting request of the page size from the virtual space allocating means 3, and sets the page size of the virtual space. Subsequently, a page allocating means 5 receives the allocation request of the page from the virtual space allocating means 3, and allocates the page. In such a way, setting of the page size being suitable for the memory request amount of the program and an allocation of the page are executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a page allocation method, and more particularly to a page allocation method in a computer system equipped with a paging structure that divides and manages memory into units called pages.

[Conventional technology]

Conventionally, in this type of page allocation method, pages are allocated with a fixed page size.

[Problem to be solved by the invention]

In the conventional page allocation method described above, the page size is fixed, so if the page size is as small as a few bytes, pages will be flushed and read from the auxiliary storage frequently, causing the paging mechanism to become inefficient. It has the disadvantage of becoming.

Furthermore, if the page size is large, such as several megabytes, there is a drawback that the efficiency of page use becomes extremely poor when the amount of memory required by the program is small.

In view of the above-mentioned points, an object of the present invention is to enable the page size to be dynamically set according to the amount of memory requested by the program, and to set the page size and allocate pages appropriate to the amount of memory requested by the program. The object of the present invention is to provide a page allocation method that enables the following.

[Means to solve the problem]

The page allocation method according to the present invention, in a computer system equipped with a paging mechanism that manages memory by dividing it into units called pages, receives memory allocation requests from processing programs that perform various processes, and calculates the amount of memory requests from the received memory allocation requests. A page size determining means for extracting and determining a page size, and receiving the memory request amount determined by the page size determining means, allocating a virtual space, and requesting a page size setting of the allocated virtual space and a page allocation request. virtual space allocation means;
The page size setting means receives a page size setting request from the virtual space allocation means and sets the page size of the virtual space, and the page allocation means receives a page allocation request from the virtual space allocation means and allocates the page. .

[Effect]

In the page allocation method of the present invention, the page size determining means receives a memory allocation request from a processing program that performs various processes, extracts the memory request amount from the received memory allocation request and determines the page size, and the virtual space allocation means The page size setting means receives the memory request amount determined by the page size determination means, allocates a virtual space, and issues a request to set the page size of the allocated virtual space and a page allocation request, and the page size setting means sets the page size from the virtual space allocation means. Upon receiving the request, the page size of the virtual space is set, and the page allocation means receives the page allocation request from the virtual space allocation means and allocates the page.

〔Example〕

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

FIG. 1 is a block diagram showing the configuration of a page allocation method according to an embodiment of the present invention.
, virtual space allocation means 3, and page size setting means 4
and page allocation means 5.

The page size determining means 2 receives a memory allocation request from a processing program l that performs various processes, extracts the memory request amount from the received memory allocation request, and determines the page size.

The virtual space allocation means 3 receives the memory request amount determined by the page size determination means 2, allocates a virtual space, and issues a request for setting the page size of the allocated virtual space and a page allocation request.

The page size setting means 4 receives a page size setting request from the virtual space allocation means 3 and sets the page size of the virtual space.

The page allocation means 5 receives a page allocation request from the virtual space allocation means 3 and allocates a page.

Next, the operation of the page allocation method of this embodiment configured as described above will be explained with reference to FIGS. 2 and 3.

When a memory allocation request is received from a processing program 1 that performs various processes, the page size determining means 2 extracts the memory request amount from the received memory allocation request and determines the page size. In a computer system in which a large page of 4 Mbytes exists, when the processing program 1 is a small program with a memory request of 8 bytes, the page size determining means 2 determines that the memory request from the processing program 1 is the large page size. Since it is less than half of 4M, the page size is determined to be 4 bytes.

When the virtual space allocating means 3 receives a memory request amount of bytes from the page size determining means 2 to 8, it divides the virtual space into fixed-sized 8 Mbyte portions of partial virtual space #0, for example, as shown in FIG. A page size setting request that allocates partial virtual space #3 of ~#n (positive integer) and sets the page size of allocated partial virtual space #3 to 4 bytes, and 2 pages of a small page of 4 bytes. A page allocation request for one page is made.

When the page size setting means 4 receives a page size setting request in bytes from the virtual space allocation means 3 to 4, the page size setting means 4 sets the partial virtual space #3 register ( The page flag (not shown) is set to indicate that the page size is 4 bytes.

When the page allocation means 5 receives a page allocation request for two byte small pages from the virtual space allocation means 3 to 4, it allocates two small pages SP1 and SF3.

On the other hand, processing program 1 has a memory requirement of, for example, 17M.
In the case of a large-scale program of bytes, the page size determination means 2 determines the page size to be 4M bytes, since the amount of memory requested by the processing program 1 is more than half of the large page size of 4M.

When the virtual space allocation means 3 receives the memory request amount of 17 Mbytes from the page size determination means 2, the virtual space allocation means 3 assigns, for example, the third
As shown in the figure, partial virtual space #31, partial virtual space 4, and partial virtual space #5 are allocated among partial virtual spaces #0 to #n, which are created by dividing the virtual space into fixed-sized 8MB each. Partial virtual space #31 A page size setting request is made to set the page size of partial virtual virtuality 4 and partial virtual space #5 to 4 MB, and a page allocation request for 5 large pages of 4 MB is made.

When the page size setting means 4 receives a page size setting request of 4 MB from the virtual space allocation means 3, the page size setting means 4 sets the partial virtual space #31, the partial virtual virtuality 4, and the partial virtual space #5.
Partial virtual space #3 register, Partial virtual space #4 register, and Partial virtual space #5 register (all not shown) used when converting virtual addresses to absolute addresses.
Set the page flag to indicate that the page size is 4 MB.

The page allocation means 5 includes virtual space allocation means 3 to 4M.
When a page allocation request for 5 large pages of bytes is received, large pages LPI, LP3 . LP5
．． Assign LP6 and LP7.

Next, a method of converting a virtual address to an absolute address will be explained.

First, the address translation mechanism (not shown; regardless of whether it is hardware or software) refers to the page flag of the partial virtual space i (i is an integer from 1 to n) register corresponding to the virtual address. . If the page flag indicates that the page size is 4 bytes, the page number is obtained by dividing the virtual address by 4, and the remainder is used as the in-page relative address. If the page flag indicates that the page size is 4M bytes, the page number is obtained by dividing the virtual address by 4M, and the remainder is used as the intra-page relative address.

In the explanation of the operation of the above embodiment, the page size determining means 2 sets the page size to the small page size based on whether the memory request amount from the processing program 1 is more than half or less than half of the large page size 4M. 4 or a large page size of 4M, but
It goes without saying that the page size determining means 2 may use other criteria for determining the page size.

〔Effect of the invention〕

As explained above, in a computer system equipped with a paging mechanism, the present invention provides a page size determination means, a virtual space allocation means, a page size setting means, and a page allocation means. This makes it possible to set the size and allocate pages, and has the effect of improving page usage efficiency without deteriorating the efficiency of the paging mechanism.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a page allocation method according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing an example of small page allocation in the page allocation method of this embodiment, and FIG. FIG. 3 is an explanatory diagram showing an example of large page allocation in the page allocation method of the embodiment. In the figure, 1... processing program, 2... page size determining means, 3... virtual space allocating means, 4... page size setting means, 5... page allocating means.

Claims (1)

[Claims] In a computer system equipped with a paging mechanism that divides and manages memory into units called pages, a computer system that receives memory allocation requests from processing programs that perform various processes and extracts the memory request amount from the received memory allocation requests. and a virtual space that receives the memory request amount determined by the page size determination means, allocates a virtual space, and issues a page size setting request and page allocation request for the allocated virtual space. an allocation means; a page size setting means for receiving a page size setting request from the virtual space allocation means and setting a page size of the virtual space; and a page allocation means for receiving a page allocation request from the virtual space allocation means and allocating a page. A page allocation method characterized by having a means.