JP2000155695A - Qos controller, qos controlling method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a QoS controller which fast performs QoS control in a built-in type real time system. SOLUTION: When a QoS control task 11 receives notice that it is in an overload state from a DL error processing task 13, it reduces the value of a QoS level 31 by one. The task 11 refers to a QoS table 16 and accesses the QoS handler of a task having the difference of a CPU utilization factor with the value of the level 31 after change as an argument. On the other hand, when it receives notice that it is in a low load state from an idle time monitoring task 12, the task 11 refers to the table 16 and accesses the QoS handler of a task having the difference of a CPU utilization factor with the value of the level 31 after change as an argument.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a QoS control device, a QoS control method, and a recording medium suitable for an embedded real-time system.

[0002]

2. Description of the Related Art With the development of microprocessor technology,
MPU (Micro Proc) is used in many personal electronic devices such as audio / video equipment, televisions, mobile phones, electronic musical instruments, game machines, washing machines, air conditioners, and lighting equipment.
essor Unit) and one-chip microcomputer (MCU; Micro Cont)
roller unit) and other microcomputers. Hereinafter, a system in which a microcomputer is incorporated for controlling devices is referred to as an “embedded system”.
Such an embedded system has been developed with the ITRON (Industr
ial TRON (TRON: The Real-time Operating system Nucle
us)) and the like, a case using a real-time OS (Operating System) is becoming common.

For example, an embedded system using such a real-time OS in a car navigation device (hereinafter, referred to as an “embedded real-time system”).
Then, CD-ROM (Compact Disk Read-Only Memor)
y) and device control such as sensors, as well as Web (World Wid
e Web) It can also provide multimedia services such as displaying pages, playing videos, and playing audio. In such an embedded real-time system, not only must resources of the limited system be minimized due to cost and space issues, but resources must be allocated preferentially to real-time tasks for control. . For this reason, in the embedded real-time system, it is necessary to process the multimedia service task by efficiently using the remaining resources.

Recently, in order to utilize limited resources efficiently in embedded real-time systems,
The quality of service of the task according to the amount of available resources (Q
A QoS control technique for changing the quality of service (oS) is applied. QoS control refers to lowering the service quality (calculation accuracy, control accuracy) to reduce the load when the load on the system exceeds an assumed maximum value. Hereinafter, the QoS control will be described using a distributed multimedia system as an example.

[0005] QoS control has traditionally been used in distributed systems that provide multimedia services. In a distributed multimedia system, generally, an unspecified number of user programs are connected to a server. That is, the user program connects to the server via the network, receives multimedia data such as images and sounds stored in the storage device of the server or generated by the server, and displays it on a predetermined screen. And so on.

However, since the resources of the server and the communication bandwidth of the network are limited, when a large number of user programs request a multimedia service and the server or the network is overloaded, it is not always necessary. In some cases, the QoS required by the user program cannot be provided. Further, even when the server can provide high QoS, if the capability of the terminal on the user side is low or if sufficient processing cannot be performed in an overloaded state, receiving a high-quality service may be useless. In such a case, QoS control is performed to reduce the load on the server or the network or to provide a service that matches the performance of the user terminal. On the other hand, when the load on the server, the network, or the terminal on the user side is reduced, etc.
Control is performed.

In the QoS control method used in such a distributed multimedia system, for example, when allocating resources for each user, the QoS is determined by negotiation between a user program and a server. The procedure of this negotiation is shown below.

First, when connecting to a server, the user program requests a receivable QoS. The server compares the current amount of resources that can be provided with the QoS request amount from the user program, and if it can be provided, accepts the QoS request, allocates resources to the user program, and provides a service.

On the other hand, the Q required by the user program
When the oS cannot be provided, the server presents the available QoS to the user program. The user program either accepts the offered QoS or renews it to the server (generally, the QoS presented by the server side).
(Lower than S) QoS. The above procedure is repeated until the server or user program accepts the offered QoS. After the QoS request is accepted or the QoS presented by the server is accepted, the user program performs a process corresponding to the QoS.

[0010] When the server or the network is overloaded, or conversely, when the server or the network is under a low load, the server sends a QoS change request to the user program. In response to this QoS change request, the user program newly requests the server for QoS. Thereafter, the same processing as the processing when the above-mentioned user program connects to the server is performed. On the other hand, when the user program is overloaded or, conversely, is under low load, the user program sends a QoS change request. This also performs the same processing as the processing when the user program connects to the server.

In the QoS control method used in the distributed multimedia system, all user programs are of the same type. As a policy for allocating resources to each user program, a method is used such that resource allocation is fair, or a method of allocating resources according to a predetermined ratio is used.

By using the QoS control method described above in an embedded real-time system,
For example, when providing a high-quality multimedia service, a task for the multimedia service can be processed by efficiently using the remaining resources.

[0013]

However, in the above-described conventional QoS control method, a certain amount of time is required for the QoS control processing. For example, in the above-described distributed multimedia system, since an unspecified number of user programs connect to the server, it has been impossible for the server to grasp the QoS request amounts of all user tasks in advance. For this reason, in the conventional QoS control method,
By negotiating with the user program, the server checks whether the QoS request amount of the user program is within the available resource amount and determines resource allocation. For this negotiation, communication and synchronization are required, and these processes involve a context switch, so that it took some time. For this reason, QoS
In a built-in real-time system using a control method, there is a problem that a high-speed processing of a user task (application task) is required, but a processing delay cannot be prevented.

In the conventional QoS control system described above, it is difficult to preferentially allocate resources only to a specific task. For example, in the above-described distributed multimedia system, since all the user programs to be subjected to QoS control are the same type of programs that handle audio and video streams, resources are distributed fairly, or according to a predetermined ratio. QoS control for allocating resources has been performed. For this reason, in an embedded real-time system using the QoS control method, there is a problem that resources cannot be preferentially allocated to a real-time task for control, so that control delay cannot be prevented.

[0015] The present invention has been made in view of the above-described circumstances, and has been described in an embedded real-time system.
QoS control device capable of high-speed control, QoS
It is an object to provide a control method and a recording medium.

[0016]

In order to achieve the above object, a QoS control device according to a first aspect of the present invention provides a service for a task started under the control of an OS that manages resources in a computer system. Quality (Qo
A QoS control device for changing S), wherein the QoS control device in the computer system has a predetermined QoS class.
Level value storage means for storing the current level value of S; quota registration means for registering a resource quota corresponding to the QoS class, which is predetermined for the activated task; Quota storage means for storing the quota of the corresponding resource, and QoS for determining the QoS for the task according to the resource quota stored in the quota storage means determined from the level value stored in the level value storage means Deciding means, resource amount monitoring means for detecting excess or deficiency of resources in the computer system, and when the resource amount monitoring means detects excess or deficiency of resources in the computer system, the level value is stored in the level value storage means. QoS control means for changing the level value of the task and changing the QoS for the task.

According to the present invention, the level value storage means includes:
It stores a predetermined QoS class, eg, the current level value of QoS in the computer system at levels 0 to 6. The quota registering unit registers a resource quota corresponding to a predetermined QoS class for each activated task, for example, a required resource amount. The quota storage means,
The resource quota corresponding to the QoS class given by the quota registering means is stored. The QoS determining means determines the QoS for the task according to the resource quota stored in the quota storing means determined from the level value stored in the level value storing means, and requests, for example, the OS to perform control. The resource monitoring means detects excess or deficiency of resources in the computer system due to, for example, a deadline error or the like. QoS
The control means increases or decreases the level value stored in the level value storage means when the resource amount monitoring means detects excess or deficiency of the resources in the computer system, and controls the QoS for the task.
To change. As a result, QoS control can be performed at high speed.

In the above-mentioned QoS control device, the resource amount monitoring means detects at least a resource shortage, and the QoS control means sets the allocation amount storage when the resource amount monitoring means detects a resource shortage. The level value stored in the level value storage means may be reduced to change the QoS for the task so that the resource allocation amount stored in the means decreases. In this case, the resource shortage is properly detected and the QoS
Control can be performed at high speed.

In the above QoS control device, the resource amount monitoring means detects at least a surplus of resources, and the QoS control means executes the processing of storing the allocated amount when the resource amount monitoring means detects a surplus of resources. The level value stored in the level value storage means may be increased to change the QoS for the task so that the resource allocation amount stored in the means increases. In this case, the surplus of resources is appropriately detected, and the QoS
Control can be performed at high speed.

In order to achieve the above object, a second aspect of the present invention is provided.
The QoS control apparatus according to the aspect of the present invention changes the quality of service (QoS) for a task started under the control of an OS that manages resources in a computer system.
An S control device, a level value storage means for storing a current level value of QoS in the computer system at a predetermined QoS class, and a predetermined QoS class corresponding to a task being activated. Quota registering means for registering a quota of resources to be assigned; quota storage means for storing a quota of resources corresponding to the QoS class;
QoS determining means for determining a QoS for a task in accordance with a resource allocation amount stored in the allocation amount storage means determined from the level value stored in the level value storage means, and a level value stored in the level value storage means The utilization rate calculating means for calculating the utilization rate of the resources in the computer system according to the resource quota stored in the quota storage means determined from the following, and the resource utilization rate calculated by the utilization rate calculating means is predetermined. And a QoS control unit that changes a level value stored in the level value storage unit to change a QoS for a task so that the QoS value falls within the set range.

According to the present invention, the level value storage means includes:
It stores a predetermined QoS class, eg, the current level value of QoS in the computer system at levels 0 to 6. The quota registering unit registers a resource quota corresponding to a predetermined QoS class for each activated task, for example, a required resource amount. The quota storage means,
The resource quota corresponding to the QoS class given by the quota registering means is stored. The QoS determining means determines the QoS for the task according to the resource quota stored in the quota storing means determined from the level value stored in the level value storing means, and requests, for example, the OS to perform control. The utilization rate calculating means calculates the utilization rate of the resources in the computer system according to the resource quota stored in the quota storage means determined from the level value stored in the level value storage means. The QoS control means increases or decreases the level value stored in the level value storage means and changes the QoS for the task so that the resource usage rate calculated by the usage rate calculation means falls within a predetermined range. . As a result, Qo
By performing the S control at a high speed, the resource utilization of the entire system can be quickly adjusted to an appropriate value.

The QoS control apparatus includes effective task management means for managing effective tasks that regularly use resources in the computer system at least by starting and waking up, and the utilization rate calculating means includes: According to the effective task managed by the task management means, the utilization rate of the resources in the computer system is calculated, and the QoS is calculated.
The control unit is configured to reduce the resource allocation amount stored in the allocation amount storage unit so that the resource usage ratio calculated by the usage ratio calculation unit does not exceed a predetermined maximum value. The level value stored in the level value storage means is reduced, and the QoS for the task of the QoS determination means is reduced.
May be changed. In this case, by capturing an effective task that constantly uses resources and performing QoS control at high speed, the resource utilization of the entire system can be quickly adjusted to an appropriate value.

The QoS control device includes invalid task management means for managing an invalid task that at least terminates and waits for processing and thus does not constantly use resources in the computer system. Calculating a utilization rate of a resource in the computer system according to the invalid task managed by the management means;
The control means controls the level so that the resource quota stored in the quota storage means is increased so that the resource utilization calculated by the utilization calculation means exceeds a predetermined minimum value. The level value stored in the value storage means may be increased to change the QoS for the task of the QoS determination means. In this case, by catching an invalid task that does not constantly use resources and performing QoS control at high speed, the resource utilization of the entire system can be quickly adjusted to an appropriate value.

To achieve the above object, a third aspect of the present invention is provided.
In the QoS control method according to the aspect of the present invention, a QoS for changing the quality of service (QoS) for a task started under the control of an OS for managing resources in a computer system is provided.
An S control method, comprising: a quota obtaining step of obtaining a resource quota corresponding to a predetermined QoS class for each running task; and a QoS in the computer system at the predetermined QoS class. A QoS determining step of determining a QoS for a task in accordance with the resource allocation amount obtained in the allocation amount obtaining step determined from the current level value of the resource level; a resource amount monitoring step of detecting excess or shortage of resources in the computer system And a QoS control step of changing a level value and changing a QoS for a task when an excess or deficiency of resources in the computer system is detected in the resource amount monitoring step.

According to the present invention, the quota obtaining step obtains a QoS class predetermined for each running task, for example, a resource quota corresponding to levels 0 to 6. The QoS determining step includes a predetermined QoS.
The QoS for the task is determined in accordance with the resource quota obtained in the quota obtaining step determined from the current level of the QoS in the computer system in the class of, and the OS requests control, for example. The resource amount monitoring step detects an excess or deficiency of resources in the computer system due to, for example, a deadline error or the like. The QoS control step changes the level value and changes the QoS for the task when an excess or deficiency of resources in the computer system is detected by the resource amount monitoring step. As a result,
QoS control can be performed at high speed.

In order to achieve the above object, a fourth aspect of the present invention is provided.
In the QoS control method according to the aspect of the present invention, a QoS for changing the quality of service (QoS) for a task started under the control of an OS for managing resources in a computer system is provided.
An S control method, comprising: a quota obtaining step of obtaining a resource quota corresponding to a predetermined QoS class for each running task; and a QoS in the computer system at the predetermined QoS class. Determining a QoS for a task according to the resource quota obtained by the quota obtaining step determined from the current level value of the current level, and a current level of the QoS in the computer system at a predetermined QoS class A utilization ratio calculating step of calculating a utilization ratio of the resources in the computer system according to the resource allocation amount acquired in the allocation amount acquiring step determined from the value; Change the level value so that it falls within the specified range, and And QoS control step of changing the,
It is characterized by having.

According to the present invention, the quota obtaining step obtains a predetermined QoS class, for example, a resource quota corresponding to levels 0 to 6 for each activated task. The QoS determining step includes a predetermined QoS.
The QoS for the task is determined in accordance with the resource quota obtained in the quota obtaining step determined from the current level of the QoS in the computer system in the class of, and the OS requests control, for example. The utilization rate calculating step calculates the utilization rate of the resources in the computer system according to the resource quota obtained in the quota obtaining step determined from the current level value of the QoS in the computer system in the predetermined QoS class. I do. In the QoS control step, the level value is increased or decreased so that the resource utilization rate calculated in the utilization rate calculation step falls within a predetermined range, and the QoS for the task determined in the QoS determination step is changed. As a result, by performing the QoS control at a high speed, the resource utilization of the entire system can be quickly adjusted to an appropriate value.

In order to achieve the above object, a fifth aspect of the present invention is provided.
The recording medium according to the aspect of the present invention is a computer-readable recording medium for recording a program for controlling a quality of service (QoS) for a task started under the management of an OS that manages resources in a computer system. A quota obtaining step of obtaining a quota of resources corresponding to a predetermined QoS class for each task being performed, and the current level value of QoS in the computer system in the predetermined QoS class. A QoS determining step of determining a QoS for a task in accordance with the resource allocation amount obtained in the allocation amount obtaining step, a resource amount monitoring step of detecting excess or deficiency of resources in the computer system; When the system detects an excess or shortage of resources in the system, Change the value, QoS for the task
And a program for realizing a QoS control step for changing the QoS.

In order to achieve the above object, a sixth aspect of the present invention is provided.
The recording medium according to the aspect of the present invention is a computer-readable recording medium for recording a program for controlling a quality of service (QoS) for a task started under the management of an OS that manages resources in a computer system. A quota obtaining step of obtaining a quota of resources corresponding to a predetermined QoS class for each task being performed, and the current level value of QoS in the computer system in the predetermined QoS class. A QoS determining step for determining a QoS for a task according to the resource allocation obtained in the allocation obtaining step; and the allocation obtaining step determined from a current level value of the QoS in the computer system in a predetermined QoS class. According to the resource quota obtained by A utilization calculating step of calculating utilization of resources in Tashisutemu, to fit in the range of utilization of the calculated resources by the utilization rate calculation step is predetermined, to change the level value, Qo for the task
Storing a program for realizing a QoS control step of changing S.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a QoS control device according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a Q according to the first embodiment of the present invention.
FIG. 1 is a block diagram illustrating an example of a configuration of a system incorporating an oS control device. The system incorporating the QoS control device shown in FIG. 1 includes a CPU 1, a memory 2, and a ROM 3.

CPU (Central Processing Unit) 1
Loads a program such as the OS 10 stored in the ROM 3 in advance into the memory 2 and performs various processes described later.

The memory 2 is a RAM having a predetermined capacity.
(Random Access Memory), the OS 10 stored in the ROM 3 is loaded, and the application tasks 20-1 to 20-n are executed on the OS 10.

The ROM 3 stores programs such as the OS 10 in advance. Note that the ROM 3 is for storing programs such as the OS 10 and may be replaced with a secondary storage device such as a flash memory or a hard disk.

The CPU 1, the memory 2, and the RO
M3 is an integrated one-chip microcomputer (MCU)
Etc.).

The OS 10 has a real-time kernel 19
A QoS control task 11, an idle time monitoring task 12, a DL (deadline) miss processing task 13,
API30.

The real-time kernel 19 provides a basic function in the OS 10. More specifically, the real-time kernel 19 includes, in addition to functions such as memory management, task management, and inter-task synchronization provided by a general OS, a task cycle which is a characteristic function of the real-time kernel. Provide execution function.

For example, in μITRON3.0 (micro ITRON3.0 specification), which is one of the typical real-time kernels, a periodic execution function which is a feature thereof is provided as a periodic handler. In this cyclic handler, the function registered by the user is executed by the kernel at regular intervals. Generally, a real-time kernel counts up a timer or the like in the kernel using a periodic timer interrupt. As a part of the timer interrupt processing, the counter for the cyclic handler is decremented. When the counter becomes zero, the cyclic handler executes the function registered by the user. The real-time kernel can execute the task periodically by starting or waking up the task as the processing of the cyclic handler. In addition,
Regarding μITRON 3.0, “μITRON 3.0
Details are described in "Revised New Standard Handbook" (supervised by Ken Sakamura: Personal Media).

The real-time kernel 19 of the QoS control device of the present invention also provides a cyclic handler similar to μITRON 3.0. In the QoS control device of the present invention, the cyclic handler is also used for detecting a DL (deadline) error. Specifically, Q of the present invention
In the oS control device, a function for calling the DL miss processing task 13 is registered in advance in a cyclic handler for periodically executing the task. As a cycle of the handler, a deadline time indicating a final deadline (relative time from the start time of the task) expected to complete the processing of the task is given. As a result, when the deadline time elapses from the scheduled start time of the task (the time at which the cyclic handler for periodic execution is executed), the cyclic handler for deadline miss detection is executed. Deadline processing is performed.

The QoS control task 11 is an OS module for performing QoS control, and has a higher priority than the application tasks 20-1 to 20-n. The QoS control task 11 has a QoS level 31 and
It has a QoS table 16 and a QoS handler table 17.

The QoS level 31 is a numerical value defining a level when performing QoS control. QoS control task 11
Is the QoS level 31 according to the change of the system load.
Increase or decrease the value of.

The QoS table 16 is a table in which the required resource amount of each task is represented as a table corresponding to the QoS level 31. In the embodiment of the present invention, QoS
Since only the CPU time is handled as a resource in the control task, the QoS table 16 pre-records the CPU usage rate of each task, that is, the CPU usage time per unit time. FIG. 2 shows an example of the QoS table 16. As shown in FIG. 2, four tasks 0 to 3 are registered in the QoS table 16. For example, if the value of the QoS level 31 is 2, the task 0
The CPU utilization rates of “.about.3” are “0.4” and “0.
2 "," 0.0 ", and" 0.2 ".
As described above, the QoS control task 11 has the QoS level 31
The resource request amount of each task can be determined by referring to the QoS table 16 according to the value of.

The QoS handler table 17 shows the QoS handler of each task as a table for the task number. The QoS handler is actually the QoS
This function is called when performing control and is used to change the processing content of the application task. When the task (task number) to be subjected to the QoS control is determined, the QoS control task 11 can determine the QoS handler for the task by referring to the QoS handler table 17.

The idle time monitoring task 12
This is a task to check idle time. When the acquired idle time exceeds a predetermined value, the idle time monitoring task 12 wakes up the QoS control task 11. In kernels for workstations such as UNIX, a function to check the CPU utilization of the entire system is provided.
The idle time monitoring task can be easily realized. That is, the idle time can be monitored only by periodically checking the CPU utilization of the entire system.

However, a kernel in an embedded system generally has no means for checking the CPU utilization of the entire system. For this reason, in the QoS control device of the present invention,
The idle time monitoring task 12 is set as the task with the lowest priority, and a predetermined loop process is executed. That is,
By measuring the processing time (loop processing time) of the idle time monitoring task 12, the idle time of the CPU 1 can be checked. For example, when the processing time of the idle time monitoring task 12 is originally 10 ms, the measured processing time of the idle time monitoring task 12 is actually 10 ms.
If it is 0 ms, the idle time monitoring task 12 determines that it is using only 10% of the total CPU time of the system. That is, the idle time monitoring task 12
Can estimate that the idle CPU utilization at this time is 10%.

When detecting the deadline miss, the DL miss processing task 13 suspends the execution of the task in which the deadline miss has occurred, and wakes up the QoS control task 11. In addition, each application task 20-1 to 20
The -n deadline is set at each startup.

API (Application Programming Interface)
ace) 30 is an application task 20-1 to 20
-N is a set of system call interfaces (programs) for using the functions and the like of the OS 10, and Qo
S-table / QoS handler registration system call 14 is included.

The QoS table / QoS handler registration system call 14 is executed by the application tasks 20-1 to 20-1.
20-n QoS table entries 22-1 to 22-n
And the QoS handlers 21-1 to 21-n.

Application tasks 20-1 to 20-
n is an application program executed on the OS 10. Application tasks 20-1 to 20
-N is the corresponding QoS handler 21-1 to 21-2
1-n and QoS table entries 22-1 to 22-n
And

The QoS handlers 21-1 to 21-n are called when actually performing the QoS control, and are functions for changing the processing contents of the corresponding application tasks 20-1 to 20-n.

QoS table entries 22-1 to 22-
n is the corresponding application task 20-1 to 20
9 is a table showing the CPU utilization of −n as a table for the value of the QoS level 31. As described above, in the embodiment of the present invention, the QoS control task 11 handles only CPU time as a resource. for that reason,
The QoS table entries 22-1 to 22-n are stored in the CPU
The interrupt rate is calculated as “execution time / period” for tasks that are executed periodically, and “execution time × number of executions per second” for tasks that are executed periodically. In this case, it is represented by “execution time / shortest interrupt interval”.

Application tasks 20-1 to 20-
n is a task executed periodically, a task executed aperiodically, an interrupt handler, and the like. Although the interrupt handler is not strictly a task, it cannot be ignored in calculating the CPU utilization, and is therefore regarded as one of the application tasks. Also, it is assumed that the execution time and the like for the application tasks 20-1 to 20-n executed in the real-time system are obtained in advance. In other words, for a task that is executed periodically, the cycle, execution time, and deadline time are set. For a task that is executed aperiodically, the execution time and how many times the task is executed within a certain time are determined by an interrupt. As for the handler, it is assumed that the shortest interrupt interval and the execution time are determined in advance.

Application tasks 20-1 to 20-
The actual processing of n may vary. Nevertheless, the processing related to the QoS control is performed by the application tasks 20-1 to 20-2
0 to n are common. Therefore, the process related to the QoS control will be described below using the application task 20-1 as an example.

When the task is initialized, the application task 20-1 registers the QoS handler 21-1 and the QoS table entry 22-1 in the QoS control task 11. If the application task 20-1 is, for example, a moving image display task, the QoS handler 21-
As for 1, the value of the QoS level 31 is passed by an argument, and the frame rate and the resolution are changed. That is, when the value of the QoS level 31 is lower than before, the QoS handler 21-1 decreases the frame rate and the resolution to reduce the CPU utilization, while the value of the QoS level 31 is higher than before. In order to increase CPU utilization,
Increase frame rate and resolution. More specifically, taking the case of changing the frame rate as an example,
If the CPU utilization is 0.4 when the frame rate is 20 frames / sec, the CPU utilization is reduced to 0.2 or 0.2.
In order to reduce the number to 1, the QoS handler 21-1 changes the frame rate to 10 frames / second or 5 frames / second, respectively.

Hereinafter, the operation of the system incorporating the QoS control device according to the first embodiment of the present invention will be described in detail. As a premise, the QoS table entry 2 of the application tasks 20-1 to 20-n is assumed.
2-1 to 22-n and QoS handlers 21-1 to 21-21
-N needs to be registered in the QoS table 16 and the QoS handler table 17 before the execution of the task starts. First, the QoS table 16 and Q
The registration of the oS handler table 17 will be described.

This application task 20-1 to 20-2
A part of 0-n is generated by a task that has already been generated while the OS 10 is partially booted. That is, OS10
At the time of booting, an initial task (not shown) generates a QoS control task 11, an idle time monitoring task 12, and a DL miss processing task 13, and starts each task. Furthermore, the initial task is application task 2
0-1 to 20-n, for example, an application task 20-i (1 ≦ i ≦ n), and a QoS table entry 22-i and a QoS handler 21-i of the generated task are stored in the QoS table / The registration is performed using the QoS handler registration system call 14.

Also, for example, application task 2
When 0-j (1 ≦ j ≦ n) dynamically generates another application task 20-k (1 ≦ k ≦ n), the application task 20-j generates the application task 20-k of the generated application task 20-k. QoS table entry 22-k
And QoS handler 21-k in the QoS table / QoS
The registration is performed using the handler registration system call 14.

Next, the QoS control operation of the system incorporating the QoS control device according to the first embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a flowchart illustrating a QoS control process performed by the QoS control task 11.

Normally, the QoS control task 11 is in a sleep state and waits for a QoS control request (step S1).
0). That is, the QoS control task 11 is woken up when a DL miss occurs due to a temporary overload state, or when there is enough CPU time.

The temporary overload state is when the task or handler exceeds the scheduled execution time. In this case, any one of the application tasks 20-1 to 20-n causes a DL miss. The DL miss processing task 13 detects the occurrence of a DL miss and notifies the QoS control task 11 that the DL miss is occurring. Also, C
If there is enough PU time, the task or handler may use less execution time than the scheduled execution time, or the task execution time may be reduced after the task execution time is reduced to eliminate the temporary overload condition. This is the case when the execution time of the task or handler that created the load state has decreased. In this case, when the idle time monitoring task 12 detects that the idle time has exceeded a predetermined value, the idle time monitoring task 12 notifies the QoS control task 11 that the free time of the CPU time has increased.

When the QoS control task 11 wakes up due to any of the above factors, it specifies the wake up factor (steps S11 and S21). That is, the QoS control task 11
First, it is determined whether a deadline miss has occurred (step S11).

The QoS control task 11 determines that a deadline miss has occurred (step S11; Ye).
s) It is determined whether or not the value of the QoS level 31 is the lowest value (step S12).

The QoS control task 11 performs QoS level 3
When it is determined that 1 is the lowest value (step S12; Y
es), the QoS control process ends. On the other hand, when it is determined that the QoS level 31 is not the lowest value (step S1).
2; No), the QoS control task 11 performs QoS level 3
The value of 1 is decreased by one (step S13).

After changing the value of the QoS level 31, the QoS control task 11 calls a QoS change process (step S14). The QoS change processing will be described later.

After the end of the QoS change processing, the QoS control task 11 determines whether or not there is a changed task (step S15).

If the QoS control task 11 determines that there is no changed task (step S15; No), the process returns to step S31. That is, the QoS control task 11 repeats the above steps S12 to S15 until a task that can change the CPU utilization is found and the CPU utilization of the entire system is reduced.

When the QoS control task 11 determines that there is a changed task (step S15; Yes),
The process ends. That is, the QoS control task 11
If it is determined in step S15 that there is a task whose CPU utilization has been changed, or if it is determined in step S12 that Q
When it is determined that the oS level 31 is the lowest value, the QoS
The control processing ends.

If it is determined in step S11 that no deadline miss has occurred (step S11).
11; No), the QoS control task 11 determines whether or not the load is low (step S21).

When the QoS control task 11 determines that the load is not low (step S21; No), the process ends without any special processing because it is a wake-up error (step S31). On the other hand, when it is determined that the load is low (step S21; Yes), it is determined whether or not the QoS level 31 is the highest value (step S22).

The QoS control task 11 performs QoS level 3
1 is determined to be the highest value (step S22; Y
es), the QoS control process ends. On the other hand, when it is determined that the QoS level 31 is not the highest value (step S2).
2; No), the QoS control task 11 performs QoS level 3
The value of 1 is increased by one (step S23).

After changing the value of the QoS level 31, the QoS control task 11 calls a QoS change process (step S24). The QoS change processing will be described later.

After the end of the QoS change processing, the QoS control task 11 determines whether or not there is a changed task (step S25).

If the QoS control task 11 determines that there is no changed task (step S25; No), the process returns to step S22. That is, the QoS control task 11 repeats the above steps S22 to S25 until a task that can change the CPU utilization is found and the CPU utilization of the entire system is increased.

If the QoS control task 11 determines that there is a changed task (step S25; Yes),
The QoS control processing ends. That is, the QoS control task 11 determines in step S25 that there is a task whose CPU utilization has been changed, or in step S2.
If it is determined in step 2 that the QoS level 31 is at the maximum value, the QoS control process ends.

Next, step 14 and step S2
4 will be described with reference to FIG. FIG. 4 is a flowchart illustrating a QoS change process performed by the QoS control task 11.

The QoS control task 11 selects one of the tasks T registered in the QoS table 16 (Step S41).

The QoS control task 11 compares the value of the QoS table 16 corresponding to the value of the QoS level 31 before the change with respect to the task T with the value of the QoS table 16 corresponding to the value of the QoS level 31 after the change ( Step S4
2).

The QoS control task 11 checks the QoS before and after the change.
The value of the QoS table 16 corresponding to the value of the S level 31;
That is, it is determined whether the CPU utilization is different (step S43).

If the QoS control task 11 determines that the CPU utilization is different (step S43; Yes), it calls the QoS handler of the task T with the changed QoS level 31 value as an argument (step S44).

The QoS control task 11 determines whether all the tasks have been checked (step S45).

If the QoS control task 11 determines that all tasks have not been checked (step S45; N
o), the process returns to step S41. That is, QoS
The control task 11 repeats the above steps S41 to S45 for all the tasks registered in the QoS table 16, and sets the QoS level 31 before and after the change.
Of the CPU utilization rate corresponding to the value of the task T, and when there is a difference in the CPU utilization rate, the QoS handler of the task T is called with the changed QoS level 31 value as an argument.

When all the tasks have been checked (step S45; Yes), the QoS control task 11
It returns to the caller whether or not there is a task whose U usage rate has been changed (step S46), and the QoS change processing ends.

Next, the QoS control operation of the present embodiment will be specifically described with reference to the QoS table 16 shown in FIG. As shown in FIG. 2, the current QoS table 16 includes four of task 0, task 1, task 2, and task 3.
One task is registered. It is also assumed that the current value of the QoS level 31 is “6”.

In this state, if any application task causes a DL miss, the QoS control task 1
1 wakes up and determines that a deadline mistake has occurred (step S11; Yes). QoS control task 11
Determines that the QoS level 31 is "6" and is not the lowest value (step S12; No), and lowers the value of the QoS level 31 by one to "5" (step S13).

In the QoS change processing, the CP of task 0
Only U utilization rate, QoS level 31 from "6" to "5"
Is determined to change from "0.5" to "0.4" (step S43; Yes).
"5" of QoS level 31 after changing the QoS handler of
Is called with an argument (step S44).

As a result, the CPU utilization of the entire system is set to 0.1, that is, 1 from the time when the DL miss occurred.
It can be expected to drop by 0%.

Further, if a DL miss still occurs, the QoS control task 11 determines that the QoS level 31 is “5” and is not the lowest value (step S1).
2; No), the value of the QoS level 31 is reduced by one to “4” (step S13). In the QoS change processing, only the CPU utilization of the task 1 is set, and the QoS level 31 is set to “5”.
Is changed from “0.3” to “0.
2 "(step S43; Ye).
s), calling the QoS handler of task 1 with the changed QoS level 31 “4” as an argument (step S4)
4).

As a result, it can be expected that the CPU utilization of the entire system is further reduced by 0.1, that is, 10%.

As described above, the value of the QoS level 31 is D
It is lowered until no L-miss occurs or becomes zero. For example, assuming that when the CPU utilization of the entire system exceeds 1, an overload occurs and a deadline miss occurs, the QoS level 31 is reduced to "3" at which the CPU utilization of the entire system becomes 0.9. .

On the other hand, if the idle time monitoring task 12 notifies that the load is low when the QoS level 31 is “3”, the QoS control task 11 wakes up and determines that the load is low. (Step S21; Y
es). The QoS control task 11 determines that the QoS level 31 is “3” and is not the highest value (step S2).
2; No), the value of the QoS level 31 is increased by one to “4” (step S23).

In the QoS change process, the CP of task 3
Only U utilization rate, QoS level 31 is "3" to "4"
Is determined to change from "0.2" to "0.4" (step S43; Yes).
"4" of QoS level 31 after changing the QoS handler of
Is called with an argument (step S44).

As a result, the CPU utilization of the entire system is set to be lower than that at the time when the low load state is notified.
2, that is, it can be expected to increase by 20%.

As described above, in the QoS control apparatus according to the first embodiment of the present invention, the QoS control task 11 performs resource allocation of each task only by referring to the QoS table 16. Therefore, resource allocation for each task can be determined without necessity of negotiation for resource allocation with the task. As a result, QoS control can be performed at high speed. Also, by appropriately setting the amount of resource required to be set in the QoS table 16 at the time of designing the embedded system, resource allocation to each task and QoS change are performed based on the QoS table 16. As a result, QoS control can be performed as intended by the designer.

Next, a QoS control apparatus according to a second embodiment of the present invention, which manages a case where a task becomes valid and a case where a task becomes invalid, will be described with reference to the drawings. explain. FIG. 5 is a block diagram illustrating an example of a configuration of a system incorporating the QoS control device according to the second embodiment of the present invention.

The system incorporating the QoS control device shown in FIG. 5 has the QoS according to the first embodiment shown in FIG.
System with built-in control device and QoS control task 4
Only 1 and API 40 are different. That is, other configurations are the same as those in FIG.

The QoS control task 41 has a new effective task table 18 in addition to the configuration of the QoS control task 11 shown in FIG.

The valid task table 18 is a list of tasks and handlers to be used when calculating the CPU utilization of the entire system. More specifically, in the valid task table 18, everything that constantly consumes CPU time is registered. Then, when the state changes to a sleep state, an I / O wait state, or the like, and the CPU time is not constantly consumed, the CPU is removed from the valid task table 18. That is, the effective task table 18 allows the CPU utilization of the entire system to be calculated appropriately. Note that the CPU utilization of the entire system is obtained by acquiring the target CPU utilization from the QoS table 16 for tasks and interrupt handlers included in the valid task table 18 and summing them.

The API 40 has a new valid task registration / deletion system call 15 in addition to the API 30 shown in FIG.

Valid task registration / deletion system call 15
Indicates that the application tasks 20-1 to 20-n are activated and change to a state in which the CPU time is steadily used.
Judgment of a change to a state in which CPU time is not constantly used due to waiting for / O, etc., and enabling / disabling a task by QoS.
Notify the control task 41. Specifically, when the application tasks 20-1 to 20-n themselves start a task, wake up the task, or enter an I / O wait state, or enter a sleep state, the valid task registration / The delete system call 15 is called to notify the QoS control task 41 of the activation / inactivation of the task.

Next, the QoS control operation of the system incorporating the QoS control device according to the second embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a flowchart illustrating a QoS control process performed by the QoS control task 11.

Normally, the QoS control task 11 is in a sleep state and waits for a QoS control request (step S5).
0). That is, the QoS control task 11 is activated when a task such as a case where a new one of the application tasks 20-1 to 20-n is started or a task in a sleep state is woken up. Alternatively, it is woken up when the task becomes invalid, such as when the task is completed or when the flag is waiting to be established. A normal system call is issued to start or pause the task, but each task performs the task validation / invalidation using the valid task registration / deletion system call 15 prior to this. . However, a task that is periodically executed periodically repeats sleep and wake-up, but periodically requires CPU time. Therefore, the task is not enabled / disabled each time it wakes up or sleeps.

When the QoS control task 11 wakes up due to any of the above factors, it specifies the wake up factor (steps S51 and S61). That is, the QoS control task 11
First, it is determined whether a valid task has been added (step S51).

When the QoS control task 11 determines that an effective task has been added (step S51; Yes),
The task is added to the valid task table 18 and registered (step S52).

The QoS control task 11 calls a utilization calculation process for calculating the CPU utilization of the entire system (step S53). The utilization rate calculation processing will be described later.

After the utilization rate calculation processing is completed, the QoS control task 11 determines the CP of the entire system obtained in the utilization rate calculation processing.
It is determined whether the U utilization rate U is larger than a predetermined maximum value Umax (step S54).

The QoS control task 11 has a CPU utilization U
Is smaller than or equal to the maximum value Umax (Step S54; No), the process proceeds to Step S67 described later.

On the other hand, when it is determined that the CPU utilization U is larger than the maximum value Umax (step S54; Yes),
The QoS control task 11 determines whether or not the value of the QoS level 31 is the lowest value (Step S55). That is, when the CPU utilization U is larger than the maximum value Umax, the QoS control task 11 regards the system as being in an overloaded state, and determines whether or not the QoS level 31 can be reduced to eliminate the overloaded state. Is determined.

[0107] The QoS control task 11 performs QoS level 3
When it is determined that 1 is the lowest value (step S55; Y
es), the process proceeds to step S57 described below. When it is determined that the QoS level 31 is not the lowest value (step S55; No), the QoS control task 11
The value of the QoS level 31 is reduced by one (step S5).
6).

After changing the value of the QoS level 31, the QoS control task 11 returns the processing to step S53.
That is, the QoS control task 11 obtains the CPU utilization rate of the entire system at the time of adding the valid task, and when the system is overloaded, repeats the above-described steps S53 to S56 to change the value of the QoS level 31. Lower sequentially.

When the CPU utilization U becomes equal to or less than the maximum value Umax, the QoS control task 11 advances the processing to step S67, which will be described later, and calls the QoS change processing. On the other hand, if the value of the QoS level 31 becomes the lowest value in step S56 before the CPU utilization U does not become equal to or less than the maximum value Umax, the QoS control task 11 returns the value of the QoS level 31 to the original value. Then, the added task is deleted from the valid task table 18, and an error indicating that the task addition has failed is returned to the task (step S57).

When it is determined in step S51 that no valid task has been added (step S5).
1; No), the QoS control task 11 determines whether or not the valid task has been deleted (step S61).

When the QoS control task 11 determines that the valid task has not been deleted (step S61; N
o), the process proceeds to step S11 in FIG. 3 of the second embodiment. In addition, the process after step S11 of FIG.
The description is omitted because it is the same as the first embodiment.

When the QoS control task 11 determines that the valid task has been deleted (step S61; Yes),
The task is deleted from the valid task table 18 (step S62).

The QoS control task 11 performs QoS level 3
It is determined whether 1 is the highest value (step S6).
3). When the QoS control task 11 determines that the QoS level 31 is the highest value (step S63; Ye)
s) The process proceeds to step S67 described below.

On the other hand, if the QoS control task 11 determines that the QoS level 31 is not the highest value (step S63; No), the QoS control task 11 calls a utilization calculation process for calculating the CPU utilization of the entire system (step S64). The utilization rate calculation processing will be described later.

The QoS control task 11 determines whether or not the CPU utilization rate U of the entire system obtained in the utilization rate calculation processing is equal to or less than a predetermined minimum value Umin (step S65).

The QoS control task 11 has a CPU utilization U
Is larger than the minimum value Umin (Step S65; No), the process proceeds to Step S67 described later. On the other hand, when determining that the CPU utilization U is equal to or smaller than the minimum value Umin (Step S65; Yes), the QoS control task 11 increases the value of the QoS level 31 by one (Step S66).

After changing the value of the QoS level 31, the QoS control task 11 returns the processing to the step S63.
That is, the QoS control task 11 performs the QoS level 31
Until the value of becomes the maximum value or the CPU utilization of the entire system becomes larger than the minimum value Umin.
63 to step S66 are repeated to increase the value of the QoS level 31.

If the value of the QoS level 31 reaches the maximum value in step S63, or if the CPU utilization of the entire system exceeds the minimum value Umin in step S65, Q
Call the oS change process (step S67). That is, the QoS control task 11 performs the same QoS change processing as in FIG. 4 described in the first embodiment, and executes the QoS handler of the task having a different CPU utilization.

Next, steps S53 and S64
Will be described with reference to FIG. FIG. 7 is a flowchart illustrating a utilization rate calculation process performed by the QoS control task 11.

First, the QoS control task 11 sets an initial value “0” to the CPU utilization U (step S71).

The QoS control task 11 selects one of the tasks T registered in the valid task table 18 (Step S72).

The QoS control task 11 sets the CPU utilization of the task T corresponding to the current value of the QoS level 31 to the QoS level.
C from the S table 16
It is added to the PU utilization rate U (step S73).

The QoS control task 11 determines whether or not the CPU utilizations of all tasks have been added (step S74). If the QoS control task 11 determines that the CPU utilizations of all tasks have not been added (step S74; No), the process returns to step S72. That is, the QoS control task 11 stores the effective task table 1
Steps S72 to S74 are repeated for all the tasks registered in No. 8, and the CPU utilization U of the entire system is obtained.

When the CPU utilizations of all the tasks are added (step S74; Yes), the QoS control task 1
1 returns the CPU utilization U to the caller, and ends the utilization calculation processing.

According to the second embodiment of the present invention, when a task is in a state of constantly consuming CPU time and in a state of not consuming CPU time, the task is changed by the CPU utilization rate of the task. Change the QoS level. As a result, even when the CPU utilization time of the entire system greatly changes due to sleep or waking up of a task, the desired C can be promptly changed.
Can be adjusted to PU utilization. In addition, since the QoS change target task is determined by referring to the valid task table, although the QoS table is registered,
No QoS change processing or the like is performed for the task in the sleep state. Therefore, useless processing is not performed, and Q
The oS control process becomes faster.

Next, the QoS control operation of the present embodiment will be specifically described with reference to the QoS table 16 shown in FIG. It is assumed that the QoS table 16 initially registers three tasks, task 0, task 1, and task 2, except for task 3 in FIG. Also,
The value of the current QoS level 31 is “6”. Also,
The maximum value Umax of the CPU utilization of the entire system is “1.
"0" and the minimum value Umin is "0.9".

In this state, if the new task 3 becomes executable, the QoS control task 11 wakes up and determines that an effective task has been added (step S51; Ye).
s).

The QoS control task 11 adds the task 3 to the valid task table 18 (step S52), and calculates the CPU utilization U of the entire system (step S5).
3). That is, the QoS control task 11 has the CPU utilization of each task of “0.5”, “0.3”, “0.1”, and “0.4” with respect to QoS level 31 “6”. Therefore, the CPU utilization rate U of the entire system
Is calculated as “1.3”.

The QoS control task 11 determines that the obtained CPU utilization U is larger than the maximum value Umax (step S54), and lowers the value of the QoS level 31 from “6” to “5” (step S56).

The QoS control task 11 performs QoS level 3
Even if the value of 1 is changed to "5", it is determined that the CPU utilization U again obtained in step S53 is larger than the maximum value Umax, and the value of the QoS level 31 is sequentially reduced, and the CPU utilization U
Is calculated (steps S53 to S56).

The QoS control task 11 performs QoS level 3
When the value of 1 is changed to “3”, the CPU utilization U obtained in step S53 becomes “0.9”, and the maximum value Uma
x or less (step S54; No).

The QoS control task 11 sets the QoS level to “3” and sets the QoS level of the task 0,
A QoS handler is executed for task 1 and task 3 (step S67).

As a result, when a task that constantly consumes CPU time is added, control can be performed so that the overall CPU utilization does not exceed the maximum value.

On the other hand, when the QoS level 31 is “3” and the task 0, the task 1, the task 2, and the task 3 are being executed, the task 1 enters a sleep state and is invalidated. The control task 11 wakes up and determines that the valid task has been deleted (step S61; Ye).
s).

The QoS control task 11 deletes the task 1 from the valid task table 18 (step S62), and calculates the CPU utilization U of the entire system (step S6).
4). That is, in the QoS control task 11, the CPU utilization of each task excluding the task 1 with respect to “3” of the QoS level 31 is “0.4”, “0.1”, and “0.2”. Therefore, the CPU utilization rate U of the entire system
Is calculated as “0.7”.

The QoS control task 11 determines that the obtained CPU utilization U is equal to or less than the minimum value Umin (step S65), and raises the value of the QoS level 31 from “3” to “4” (step S66).

The QoS control task 11 performs QoS level 3
Even if the value of 1 is changed to "4", it is determined that the CPU utilization U again obtained in step S64 is equal to or less than the minimum value Umin, and the value of the QoS level 31 is sequentially increased, and the CPU utilization U
Is calculated (steps S63 to S66).

The QoS control task 11 performs QoS level 3
When the value of 1 is changed to “6”, it is determined to be the highest value of the QoS level 31 (Step S63; Yes).

[0139] The QoS control task 11 sets the QoS level to "6",
Then, a QoS handler is executed for task 3 (step S67).

In the first and second embodiments, Q
Qo indicates the task resource requirement for the value of oS level 31
Although it is determined using the S table 16 or the like, the resource requirement of the task may be determined using a QoS function instead of the table. Hereinafter, a description will be given of a modification according to the embodiment of the present invention, which is characterized in that the required resource amount of a task is obtained using a QoS function.

In this modification, for example, QoS level 3
A QoS function that takes a value of 1 as an argument and returns a resource request amount of each task corresponding to the argument is used. Also, the QoS table / QoS handler registration system call 14 uses a QoS function instead of a QoS table entry as an argument.

More specifically, for example, the QoS control task 11 obtains the CPU utilization rate of each task for the QoS level 31 during the utilization rate calculation processing of FIG. 7 (step S73) and the QoS control task of FIG. During the change process, when the CPU utilization of each task for the QoS level 31 before and after the change is obtained (step S42), the QoS function is called to determine the resource request amount of the application task.

In this modification, unlike the first and second embodiments using a QoS table or the like, as the number of QoS levels increases, the size of the QoS table entry increases, consuming a large amount of memory. The problem of getting lost is eliminated. That is, in this modification, the same amount of memory can always be used irrespective of the level of the QoS level. In particular, when the resource demand of the task is expressed as a simple function, the first and the second are used. The memory usage can be significantly reduced as compared with the second embodiment.

As described above, when the QoS control device according to the second embodiment of the present invention regularly consumes CPU time due to waking up of a task or the like, the CPU utilization of the task is reduced. The QoS level is reduced so that the CPU utilization of the entire system does not exceed the maximum value even if the minutes are added. Further, when CPU time is not consumed due to sleep of a task or the like, the QoS level is raised so that the CPU utilization of the entire system does not exceed the minimum value even if the CPU utilization of the task is reduced. As a result, if the CPU utilization of the entire system changes significantly due to the wake-up or sleep of the task, the CPU of the entire system is changed.
The utilization can be quickly adjusted to an appropriate value.

The broadcast system of the present invention can be realized by using a general computer system without using a dedicated system. For example, a QoS control device that executes the above-described processing is installed in a computer by installing the program from a medium (floppy (registered trademark) disk, CD-ROM, or the like) storing the program for executing any of the above. Can be configured.

The medium for supplying the program to the computer may be a communication medium (medium for temporarily and fluidly holding the program, such as a communication line, a communication network, or a communication system). For example, the program may be posted on a bulletin board (BBS) of a communication network and distributed via the network. Then, by starting this program and executing it in the same manner as other application programs under the control of the OS, the above-described processing can be executed.

[0147]

As described above, according to the present invention,
In an embedded real-time system, QoS control can be performed at high speed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a configuration of a system incorporating a QoS control device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating an example of a QoS table.

FIG. 3 is a flowchart illustrating a QoS control process according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating a QoS change process according to the first embodiment of the present invention.

FIG. 5 is a block diagram illustrating an example of a configuration of a system incorporating a QoS control device according to a second embodiment of the present invention.

FIG. 6 is a flowchart illustrating a QoS control process according to a second embodiment of the present invention.

FIG. 7 is a flowchart illustrating a utilization rate calculation process for determining a CPU utilization rate of the entire system according to the second embodiment of the present invention;

[Description of Signs] 1 CPU 2 Memory 3 ROM 10 OS 11 QoS control task 12 Idle time monitoring task 13 DL miss processing task 14 QoS table / QoS handler registration system call 15 Valid task registration / deletion system call 16 QoS table 17 QoS handler Table 18 Effective task table 19 Real-time kernel 20-1 (20-n) Application task 21-1 (21-n) QoS handler 22-1 (22-n) QoS table entry 30 API 31 QoS level 40 API 41 QoS control task

Claims (10)

[Claims] 1. A QoS control device for changing the quality of service (QoS) for a task started under the control of an OS that manages resources in a computer system, wherein the QoS control device is provided with a predetermined QoS class. Level value storage means for storing a current level value of QoS, quota registration means for registering a resource quota corresponding to a QoS class, which is predetermined for a running task, and a class of the QoS An allocation storage means for storing an allocation amount of resources corresponding to the above, and a QoS for a task is determined according to an allocation amount of resources stored in the allocation amount storage means determined from a level value stored in the level value storage means. QoS determining means; resource amount monitoring means for detecting excess or deficiency of resources in the computer system; Comprises: QoS control means for changing a level value stored in the level value storage means and changing QoS for a task when an excess or deficiency of resources in the computer system is detected. Control device. 2. The resource amount monitoring means detects at least a resource shortage, and the QoS control means stores the resource amount in the quota storage means when the resource amount monitoring means detects a resource shortage. The level value stored in the level value storage means is reduced so that the allocated amount of
The QoS control device according to claim 1, wherein the QoS is changed. 3. The resource amount monitoring means detects at least a resource surplus, and the QoS control means stores the resource amount in the quota storage means when the resource amount monitoring means detects a resource surplus. The level value stored in the level value storage means is increased so that the allocated amount of the
The QoS control device according to claim 1 or 2, wherein the QoS is changed. 4. A QoS control device for changing the quality of service (QoS) for a task started under the control of an OS that manages resources in a computer system, wherein the QoS control device has a predetermined QoS class. Level value storage means for storing a current level value of QoS, quota registration means for registering a resource quota corresponding to a QoS class, which is predetermined for a running task, and a class of the QoS An allocation storage means for storing an allocation amount of resources corresponding to the above, and a QoS for a task is determined according to an allocation amount of resources stored in the allocation amount storage means determined from a level value stored in the level value storage means. QoS determination means stored in the quota storage means determined from the level value stored in the level value storage means Utilization rate calculating means for calculating the utilization rate of the resources in the computer system according to the allocated amount of the source; and the level so that the utilization rate of the resources obtained by the utilization rate computing means falls within a predetermined range. Change the level value stored in the value storage means, and
QoS control apparatus, comprising: changing QoS. 5. An effective task managing means for managing an effective task which constantly uses resources in the computer system at least by starting and waking up, wherein the utilization rate calculating means includes an effective task managing means for the effective task managing means. According to the managed effective task, the utilization rate of the resource in the computer system is calculated only for the effective task, and the QoS control means determines that the utilization rate of the resource calculated by the utilization rate calculating means is a predetermined maximum. Lowering the level value stored in the level value storage means and changing the QoS for the task so that the resource allocation amount stored in the allocation amount storage means decreases so as not to exceed the value. The QoS control device according to claim 4, characterized in that: 6. An invalid task managing means for managing an invalid task that does not constantly use resources in the computer system at least after termination and waiting for processing, wherein the utilization rate calculating means manages the invalid task by the invalid task managing means. In accordance with the invalid task, the utilization rate of the resources in the computer system excluding the invalid task is calculated, and the QoS control means determines that the utilization rate of the resource calculated by the utilization calculation means is a predetermined minimum. Changing the QoS for the task by increasing the level value stored in the level value storage means so that the resource allocation amount stored in the allocation amount storage means increases so as to exceed the value. The QoS control device according to claim 4 or 5, wherein 7. A QoS control method for changing the quality of service (QoS) for a task started under the control of an OS that manages resources in a computer system, wherein the QoS control method is predetermined for each running task. A quota obtaining step for obtaining a resource quota corresponding to the QoS class; and a resource quota obtaining step determined from the current level value of the QoS in the computer system in the predetermined QoS class. According to the quota,
A QoS determining step of determining a QoS for the task; a resource amount monitoring step of detecting an excess or deficiency of resources in the computer system; and an excess or deficiency of resources in the computer system is detected by the resource amount monitoring step. A QoS control step of changing a QoS value for a task by changing a level value. 8. A QoS control method for changing the quality of service (QoS) for a task started under the control of an OS that manages resources in a computer system, wherein the QoS control method is predetermined for each running task. A quota obtaining step for obtaining a resource quota corresponding to the QoS class; and a resource quota obtaining step determined from the current level value of the QoS in the computer system in the predetermined QoS class. According to the quota,
A QoS determining step of determining a QoS for a task; and a resource quota obtained by the quota obtaining step determined from a current level value of the QoS in the computer system in a predetermined QoS class.
A utilization ratio calculating step of calculating the utilization ratio of the resources in the computer system, and changing the level value so that the utilization ratio of the resources calculated by the utilization ratio calculation step falls within a predetermined range. A QoS control method, comprising: a QoS control step of changing a QoS. 9. A computer-readable recording medium for recording a program for controlling a quality of service (QoS) for a task started under the control of an OS that manages resources in a computer system, the program being activated. A quota obtaining step of obtaining a quota of resources corresponding to a predetermined QoS class for each task; and obtaining the quota determined from a current level value of the QoS in the computer system in the predetermined QoS class. A QoS determining step of determining a QoS for a task in accordance with the resource allocation amount obtained in the step, a resource amount monitoring step of detecting excess or deficiency of resources in the computer system, and a resource amount monitoring step in the computer system. If a resource shortage is detected, change the level value. And a QoS control step of changing a QoS for the task. 10. A computer-readable recording medium for recording a program for controlling a quality of service (QoS) for a task started under the control of an OS for managing resources in a computer system, the program being activated. A quota obtaining step of obtaining a quota of resources corresponding to a predetermined QoS class for each task; and obtaining the quota determined from a current level value of the QoS in the computer system in the predetermined QoS class. A QoS determining step for determining the QoS for the task according to the resource allocation amount obtained in the step; and the allocation amount obtaining step determined from the current level value of the QoS in the computer system in the predetermined QoS class. Computer system according to the allocated resources A utilization ratio calculating step of calculating the utilization ratio of the resources in the system; and changing the level value so that the utilization ratio of the resources calculated by the utilization ratio calculation step falls within a predetermined range, and setting the QoS for the task.
A computer-readable recording medium, which stores a program for realizing a QoS control step of changing the parameter.