JPH07121464A - Storage area allocation control system - Google Patents

Abstract

PURPOSE:To properly and automatically ad just the secured amount of a storage area by delaying the securing of the new storage area corresponding to the deficiency of the storage area due to the increase of the flow rate of communication data and securing the new storage area only when the deficiency of the storage area is not solved within delay time. CONSTITUTION:A buffer control part 124 starts a buffer segment release delay timer when the buffer in use is eliminated within a buffer segment 1250 and processes a buffer securing request in holding when the request exists. When a timer terminates and the notification is received from a timer control part 127, a buffer segment 1250 is removed from a buffer pool 125 and a memory is released. When a buffer segment securing delay timer terminates and the effect is notified from the timer control part 127, memory is secured via a memory control part 128, it is initialized as a buffer segment and it is added to a buffer pool 125. Thus, the frequency occurrence of the securing/release of the storage area is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage area allocation control method for temporarily holding communication data in a node for achieving a network system or a terminal connected to the network system.

[0002]

2. Description of the Related Art Conventionally, as a method for allocating a storage area required for communication processing according to the flow rate of communication data, there has been disclosed in JP
63-198449.

[0003]

In the above-mentioned prior art, a new storage area is secured as soon as the storage area becomes insufficient due to an increase in the flow rate of communication data, and conversely, a storage area becomes available as soon as the flow rate of communication data decreases. If the flow rate of communication data fluctuates frequently in order to release the surplus storage area, the storage area is frequently reserved and released, and the processing overhead increases.

Further, in order to reduce this overhead, if the storage area once secured is not released,
When the flow rate of communication data increases only momentarily, the storage area secured when the flow rate of communication data becomes maximum is not used when the flow rate of communication data is low, and the use efficiency of the storage area decreases.

The object of the present invention is to smooth the fluctuation of the flow rate of communication data and reflect it in the allocation of the storage area.
The object of the present invention is to appropriately and automatically adjust the secured amount of the storage area to improve the use efficiency of the storage area and to reduce the processing overhead of securing and releasing the storage area.

[0006]

To achieve the above object, when a new storage area is secured, a storage area securing delay timer for delaying execution of the securing process by a system-determined time, and a storage area securing delay Provided are means for stopping the storage area reservation delay timer when it becomes unnecessary to secure a new storage area before the timer expires, and means for securing a new storage area when the storage area reservation delay timer expires. . Further, there is provided means for calculating and setting the value of the storage area reservation delay timer in association with the amount of use of the storage area at any time.

Similarly, when the surplus storage area is released, the storage area release delay timer that delays the execution of the release processing by a system-determined time and the release of the surplus storage area before the storage area release delay timer expires. When the storage area release delay timer expires, a means for stopping the storage area release delay timer and a means for releasing the surplus storage area when the storage area release delay timer expires are provided. Further, there is provided means for calculating and setting the value of the storage area release delay timer in association with the total amount of use of the storage area at any time.

[0008]

When the flow rate of communication data increases and the storage area required for processing becomes insufficient, a new storage area is secured, but the storage area securing delay timer is activated to delay this by the time set by the system. It If the flow rate of communication data decreases before the expiration of the storage area reservation delay timer and it becomes unnecessary to reserve a new storage area, the storage area reservation delay timer is stopped. A new storage area is secured when the storage area securing delay timer expires while the storage area is insufficient for the flow rate of communication data.

When the flow rate of communication data decreases and the storage area becomes full, the excess storage area is released, but the storage area release delay timer is started in order to delay the surplus storage area by the time defined by the system. Before the expiration of the storage area release delay timer, if the flow rate of communication data increases again and the release of the storage area becomes unnecessary, the storage area release delay timer is stopped.
When the storage area release delay timer expires with the storage area remaining for the flow rate of communication data, the surplus storage area is released.

When the storage area reservation delay timer or the storage area release delay timer is activated, the timer value is set larger as the amount of use of the storage area at that time increases, so that a steady flow rate of communication data is obtained. Becomes larger, the execution frequency of the storage area reservation / release processing decreases.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a block diagram showing the structure of means for realizing the present invention.

At the time of transmission, the application interface unit (121) of the communication control program (12) copies the transmission data passed from the application program (11) to a buffer secured via the buffer management unit (124) to perform a protocol. It is passed to the processing unit (122). This buffer has a network interface section (12
When the data is transmitted to the network (13) in 3), it is returned to the buffer management section.

At the time of reception, the network interface unit secures a buffer via the buffer management unit, stores the data received from the network in this buffer, and passes it to the protocol processing unit. This buffer is returned to the buffer management unit when the data is passed to the application program.

The buffer management unit is a memory management unit (12
From 8), a memory is secured in a unit determined by the system, which is used as a buffer segment (1250) and a plurality of buffer segments are managed as a buffer pool (125). When a buffer is allocated according to a request from the application interface unit, the network interface unit, or the protocol processing unit, an unused buffer is allocated from the buffer pool managed by the buffer management unit, instead of allocating a memory for each request. The buffer segment is secured when the remaining number of unused buffers in the buffer pool becomes equal to or less than the threshold set by the system. When the buffer is returned to the buffer management section,
The buffer becomes unused. When all the buffers in the buffer segment have become unused, the buffer segment is judged to be releasable.

The delay timer management unit (126) lengthens the values of the buffer segment reservation delay timer and the buffer segment release delay timer as the capacity of the entire buffer pool at that time increases, and shortens as the capacity decreases. .

When the buffer control delay timer or the release delay timer expires, the timer control section (127) notifies the buffer management section to that effect.

The memory management unit (128) secures or releases the system memory according to a request from the buffer management unit.

FIG. 2 shows the structure of the buffer segment.

The buffer segment includes one buffer segment management information section (21) and a plurality of buffers (2
2, 23). Each buffer comprises a buffer management information section (22) and a data area section (23). The buffer segment management information section stores the remaining number of unused buffers in the buffer segment, the unused buffer list pointer, and the like. The next buffer pointer, the reference position of the data storage area, and the like are stored in the buffer management information.

FIG. 3 shows a procedure of buffer allocation processing.

When the buffer management unit receives the reservation request,
First, it is checked whether or not there is an unused buffer in the buffer pool (31), and if there is, it is used and is allocated to the request source (32). If there is no unused buffer, the reservation request is temporarily suspended (38). When a factor for allocating a new buffer segment occurs, that is, when the remaining number of unused buffers in the buffer pool falls below the threshold set by the system (35), the buffer segment reservation delay timer is activated (36, 37). . If the buffer segment release delay timer has been started, stop it (33, 3).
4).

FIG. 4 shows the procedure of the buffer return process.

Upon receiving the buffer return request, the buffer management unit puts the buffer in an unused state and adds it to the unused buffer list of the buffer segment to which the buffer belongs (41). When it is determined that the buffer segment can be released, that is, when there is no buffer in use in the buffer segment, the buffer segment release delay timer is activated (42, 43). If there is a pending buffer reservation request, it is processed (44).

FIG. 5 shows a processing procedure when the buffer segment reservation delay timer expires.

When the buffer segment reservation delay timer expires and the timer control section notifies the buffer management section of the fact, the buffer management section reserves a memory via the memory management section (5
1) Initialize as a buffer segment and add it to the buffer pool (52). If there is a pending buffer reservation request, it is processed (53).

FIG. 6 shows a processing procedure when the buffer segment release delay timer expires.

When the buffer segment release delay timer has expired and the timer control unit notifies it, the buffer management unit removes the buffer segment from the buffer pool (61) and releases the memory (62).

FIG. 7 shows a processing procedure for a pending buffer reservation request.

When an unused buffer is generated in the buffer pool due to the reservation of a new buffer segment or the return of the buffer, the buffer management unit allocates the buffer to the pending buffer reservation request source (71 to 74). When all pending reservation requests have been processed, the remaining number of unused buffers is checked (75), and if it is equal to or greater than the threshold value, the buffer segment reservation delay timer is released (77 to 7).
8). If it is less than the threshold value, the buffer segment reservation delay timer is activated (76).

[0031]

According to the present invention, when the storage area required for communication processing becomes insufficient due to an increase in the flow rate of communication data, a new storage area is secured only when the state continues for a certain time, and communication is performed. When the storage area is left over due to a decrease in the data flow rate, the remaining storage area is released only when the state continues for a certain period of time, so the storage area is secured / released due to an instantaneous change in the communication data flow rate. Can be prevented from occurring frequently. Further, this makes it possible to secure a storage area of an amount commensurate with the steady flow rate of communication data without securing an excessive storage area.

Further, by increasing the delay time for securing / releasing the storage area as the total capacity of the secured storage area increases, the processing overhead is reduced and the finite storage capacity is secured excessively. It can delay the serious impact on the entire system.

[Brief description of drawings]

FIG. 1 is a block diagram of means for implementing the present invention.

FIG. 2 is a structural diagram of a buffer segment in FIG.

FIG. 3 is a buffer securing procedure realized by a buffer management unit in FIG.

FIG. 4 is a buffer return procedure realized by a buffer management unit in FIG.

5 is a processing procedure when the memory reservation timer expires, which is realized by the buffer management unit in FIG. 1;

6 is a processing procedure when the memory release timer expires, which is realized by the buffer management unit in FIG. 1;

FIG. 7 is a processing procedure of a pending buffer reservation request realized by a buffer management unit in FIG.

Claims (4)

[Claims] 1. In a communication control program having means for securing a necessary storage area according to a change in the flow rate of communication data, a new storage area is secured to cope with a shortage of the storage area due to an increase in the flow rate of communication data. A storage area allocation control method which delays and secures a new storage area only when the shortage of the storage area is not resolved within the delay time. 2. A storage area allocation control system according to claim 1, wherein the delay time for securing a new storage area is made longer as the storage area used at that time becomes larger. 3. A communication control program having means for securing a necessary storage area according to fluctuations in the flow rate of communication data, delaying the release of the surplus storage area due to the decrease in the flow rate of communication data, and within the delay time. A storage area allocation control method characterized in that the storage area is released only when it has not been reused. 4. A storage area allocation control system according to claim 2, wherein the delay time for releasing the surplus storage area is made longer as the storage area used at that time becomes larger.