JPS61210462A - Dynamic control method for input and output buffer mechanism - Google Patents

Abstract

PURPOSE:To effectively employ a limited input and output buffer mechanism by initially ensuring a large area when the area having an unclear capacity is maintained in an input and output buffer mechanism, using a necessary area in a time of necessity and managing the area. CONSTITUTION:An input and output buffer mechanism (IBUF) maintains therein an area of a capacity considered to be necessary. The area is divided into fields according to a necessity and used and therefore, an area management information is used. Namely, a field maximum value (the number of fields capable of being managed KNF), an array (field pointer table KFPT) in which a head position of the respective fields is stored, and a field using condition table KUST are used. By maintaining surely this area and managing it, a part of the area can be used to a necessary degree during a necessary time. Thereby, the input and output buffer mechanism IBUF can be effectively used.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for dynamically controlling an input/output buffer, and in particular, to secure a variable-length capacity area within the input/output buffer to effectively utilize the limited input/output buffer. Related to a dynamic control method for an input/output buffer mechanism (prior art) Conventionally, when securing an area within this type of input/output buffer mechanism, if the capacity of the input/output buffer mechanism is not known, it is necessary to ensure that the area does not exceed the capacity. They had secured enough capacity to accommodate the size of the building.

Therefore, in reality, it is often the case that not all of the allocated space is used, leading to wasted space in the input/output buffer mechanism, and conversely, it is not possible to exceed the limit of the allocated capacity. In addition, when securing a plurality of areas that cannot be used and whose capacity does not change significantly, there is a drawback that the limit value of the capacity of all these areas must be considered.

(Objective of the Invention) The object of the present invention is, when securing an area of unknown capacity in the input/output buffer mechanism, to first secure a large area, and then to secure the area as needed when needed. An object of the present invention is to provide a dynamic control method for an input/output buffer mechanism that effectively utilizes a limited input/output buffer mechanism by using the input/output buffer mechanism and managing its area.

(Structure of the Invention) According to the present invention, an input/output buffer mechanism that secures a large capacity area in advance, a reservation control mechanism that dynamically secures a necessary amount when using the input/output buffer mechanism, and A pointer indicating the starting position of the secured area, the capacity of the area, information on whether there is any area that can be secured behind the area, etc.
An input/output buffer that effectively utilizes the area of the input/output buffer by having a management mechanism that manages the state of the input/output buffer and a release mechanism that releases the area of the input/output buffer that has been used. A method for dynamic control of the mechanism is obtained.

(Example) Next, an example of the present invention will be described in detail with reference to the drawings.

Figure 1 shows the input/output buffer (IBUF), which was secured at the beginning in an embodiment of the present invention, and its management. , allocate one large area and divide it into fields as needed. Therefore, use the following area management information.

(1) Maximum field value (KNF) Manageable number of fields (KNF) (ii) Field pointer table (KFPT (KNT)) Array storing the start position of each field (iii)
Field usage status table (referred to as KU8T (KNT)) FIG. 2 shows the initialized state of the management information table in this embodiment. In FIG. 2, first, the management information table is initialized, the first field pointer table 1C1 is entered, and the field usage status table is entered by -1 (
If you enter (unused), initialization will be performed.

Figures 3 and 4 show how to secure an area in this embodiment. In particular, Figure 3 shows when all subsequent areas are empty, and Figure 4 shows how the following areas are occupied. In FIGS. 3 and 4, when securing an area, the field usage status table K U S '1" (I) is set to i=
Search for unused areas from 1 to I = KN F in ascending order. Now, set the size of the area you want to secure to L12. Let the size of the entire area be IBSZ.

(1) KU8T(Io)=-1(1≦I, (KN
F) is found) (1) IB8Z-KFPT(1,)+1 ≧L8Z
O(!:@(Figure 3) KFPT(Io+1)=KFPT(Io)+L8ZKU
Let ST(10)=1.

■ IB8Z-KFPT(Io)+l < L12 o
*Cannot be secured due to lack of space.

(II) KU8T(Io)=0 (1≦IO(K
When NF) looks at me, KU8T(It)=x becomes ll(I.<It≦KN
Regarding F)■ KPPT(I,)-KFPT(I,) ≧L8Z
f),! =*(Figure 4) KFPT(I, + 1) = KFPT(I.) + L
SZKFPT(Io + z) = icyp'r(Io)
+ LSZKFPT (Iz 1) = KFPT (Io
)+L8Z■ KFPT(I,)-KFPT(I.)(
LSZ O,! :*Continue searching. (l1+l) (iiD I = 1) When the field cannot be secured by searching up to KNF, the field management table overflows and cannot be secured.

FIG. 5 shows how the area is released. In Figure 5, if you want to release the area in use and make it unused,
Perform the following processing. Now, let the management number of the field you want to release be 0.

(1) 7 (-Update the field pointer table KFPT and combine consecutive unused fields.

FIGS. 6 and 7 illustrate the release of areas.

In FIGS. 6 and 7, (1) the field usage status table KUST is updated in accordance with the usage status of the field immediately after the update. In particular, as shown in Figure 6, the immediately following table is in use KUST(Io+1)=1
In this case, set KUST(I,)=1.

Also, as shown in Figure 7, the immediately following table is an unused KU.
If ST (1, +1) = -1, the immediately preceding KUST (I
I from the field after the field where s ) = 1.

KUST(I)=-IK until KUST(I)=-IK.

(Effects of the Invention) As explained above, the present invention first secures and manages a large area, and then uses a part of that area as needed when necessary, and then releases it for effective use. It has the effect of being able to

[Brief explanation of the drawing]

FIG. 1 shows an initially large area (IBUF) and its management information table (KFP) in an embodiment of the present invention.
Figure 2 shows the initialization of the management information table, and Figure 3 shows how the area is secured.In particular, if all subsequent areas are empty, Figure 4 shows how to secure an area, especially when there are areas in use in subsequent areas, and Figure 5 shows how to release an area. , Diagram showing update of field pointer table, No. 6
This figure shows the release of the area, especially when the immediately following table is in use. FIG. 7 is similar to FIG. 6, but especially when the immediately following table is unused (KUST(I )
=-1). I BUF...Input/output buffer mechanism, KFPT...
...Field pointer table, KUST...
...Field usage table.

Claims (1)

[Claims] An input/output buffer that secures a large capacity area in advance, a reservation control mechanism that dynamically secures the required amount when using the input/output buffer, a pointer that indicates the start position of the dynamically reserved area, and the capacity of the area. , a management mechanism that manages the status of the input/output buffer mechanism, such as information on whether there is an area that can be secured after the area, and a release mechanism that releases the area of the input/output buffer mechanism that has been used. A dynamic control method for an input/output buffer mechanism, characterized by effectively utilizing the area of the input/output buffer mechanism.