JP2003108393A - Load distribution method of video stream sending process and apparatus thereof, load distribution program and recording medium with the program recorded thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a load distribution method of a video stream sending process and apparatus thereof, which can prevent concentration of a load to a specific process, and to provide a distribution program and recording medium with the program recorded thereon. SOLUTION: The load distribution apparatus of the video system stream sending process is provided with a measuring means for measuring a variety of loads generated by a processing operation based on a video operation request, a notification means for notifying the load measured by the measuring means to a user request reception and load distribution process as its own load information, a management means for managing the load information notified from each video stream sending process as sending process information, and an instruction means for allocating the video stream sending process being the lightest in the loaded condition by referring to the sending process information and for instructing the connection when the connection to the video server system is required by a client.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load distribution method for a video stream transmission process, an apparatus therefor, a load distribution program, and a recording medium recording the program,
It is particularly suitable for application to a video server system in a video distribution service.

[0002]

2. Description of the Related Art Conventionally, in the load distribution method of the video stream transmission process in the video distribution service or the video server system, (1) the video stream transmission process is sent to the computer by the round robin method every time the client requests it. A method of sequentially allocating, (2) a method of comparing CPU loads of respective computers, selecting a processor having a minimum load value, and transmitting a video stream signal to a client in a video stream transmission process on the processor. It was common.

[0003]

However, the methods described in (1) and (2) above may cause the following problems.

First, in the method (1), when there are a plurality of clients who have not finished the video distribution service, the access of the clients is unevenly distributed to a specific computer on which the video stream transmission process is started. , The CPU load of the processor in which the process is activated may increase excessively.

Further, since the CPU load of each computer is compared in the method (2), it is possible to avoid the excessive increase of the CPU load, which has been mentioned as a problem of the method (1). When the CPU load values are the same, the network load, the disk access load, and the transmission bit rate usage rate may increase depending on the selected CPU.

Further, in the case of the method (2), it is general that the load value is obtained by averaging the loads obtained several times within a predetermined period set in advance. If the user accidentally suspends the video operation or performs a special operation such as fast-forwarding that is considered to be heavy, the load value will temporarily take a small value or a large value. A computer that is different from the load status may be assigned.

The present invention has been made in consideration of the above points, and a load distribution method for a video stream transmission process, a device thereof, a load distribution program, and a load distribution program capable of preventing concentration of a load on a specific process. It is intended to provide a recording medium in which a program is recorded.

[0008]

In order to solve such a problem, in the first aspect of the present invention, one or more video streams for sending a video signal to a client on a plurality of computers connected via a network. The load distribution method of the video stream transmission process when the transmission process and the user request reception / load distribution process that accepts the request from the client and allocates the video stream transmission process to the client are configured by the following processing procedures. did.

That is, the video stream transmission process is at least the CPU load, the network load, the disk access load, the playback bit rate used capacity, and the number of connected users, which are generated by the processing operation according to the video operation request from the client. Any one of them is measured, and these are notified to the user request reception / load distribution process as its own load information.

According to the second aspect of the present invention, one or more video stream transmitting processes for transmitting a video signal to a client on a plurality of computers connected via a network, and receiving a request from the client, the above-mentioned process being performed. The load distribution method of the video stream transmission process when the user request reception / load distribution process that allocates the video stream transmission process to the client is activated is configured by the following processing procedures.

That is, the user request reception / load distribution process manages the load information notified from each video stream transmission process as transmission process information, and when the client requests the connection to the video server system, these transmissions are performed. By referring to the process information, the video stream transmission process having the lightest load state is allocated and the connection is instructed.

As one aspect, any one of a CPU load, a network load, a disk access load, and a capacity utilization rate is set as a condition for determining the video stream transmitting process whose load state in the user request receiving / load balancing process is the lightest. The condition that CPUs, network load,
The load values are compared in the order of the disk access load and the capacity usage rate, and one of the conditions for considering the one with the high load value as the large load is included, and these conditions are selectable.

Another aspect is characterized in that the load value of the video stream transmission process is calculated on the assumption of a change in load due to special reproduction such as temporary stop of video operation or fast forward.

Furthermore, as another aspect, it is characterized in that an increase in load due to an increase in the number of user connections to the video stream transmission process is predicted, and this predicted value is used for calculating the load value of the video stream transmission process. And

In a sixth aspect of the present invention, one or more video stream transmitting processes for transmitting a video signal to a client on a plurality of computers connected via a network, and a request for receiving a request from the client are received. The load balancer for the video stream transmission process when the user request reception / load distribution process for allocating the video stream transmission process to the client is activated is configured by the following components.

That is, of the CPU load, the network load, the disk access load, the used capacity of the reproduction bit rate, and the number of connected users, which are provided in the video stream transmission process and are generated by the processing operation according to the video operation request from the client. Measuring means for measuring at least one of the above, a notifying means for notifying the load measured by this measuring means to the user request receiving / load balancing process as its own load information, and the user request receiving / load balancing process A management unit that is provided to manage load information notified from each video stream transmission process as transmission process information and, when a client requests a connection to the video server system, refers to these transmission process information and refers to the load status. Is the lightest video stream transmission program And a instruction means for instructing the assigned connecting process.

In a seventh aspect of the present invention, one or more video stream transmitting processes for transmitting a video signal to a client on a plurality of computers connected via a network, and receiving a request from the client to receive the request. A load distribution program for the video stream transmission process when the user request reception / load distribution process for allocating the video stream transmission process to the client is activated is configured by the following steps.

That is, at least one of the CPU load, the network load, the disk access load, the playback bit rate used capacity, and the number of connected users generated by the processing operation in response to the video operation request from the client is measured. A measurement step, a notification step of notifying the load measured by this measurement step to the user request reception / load distribution process as its own load information, and a management step of managing the load information notified in this notification step as transmission process information And when a client requests a connection to the video server system, it refers to the transmission process information managed in these management steps, assigns the video stream transmission process with the lightest load state, and instructs the connection. And an instruction step.

According to the eighth aspect of the present invention, one or more video stream transmitting processes for transmitting a video signal to a client on a plurality of computers connected via a network, and a request from the client are accepted. By assigning the video stream transmission process to the client, recording the load balancing program of the video stream transmission process when the user request reception / load balancing process is started, by recording the program configured by the following steps. Configured.

That is, at least one of the CPU load, the network load, the disk access load, the used capacity of the reproduction bit rate, and the number of connected users generated by the processing operation in response to the video operation request from the client is measured. A measurement step, a notification step of notifying the load measured by this measurement step to the user request reception / load distribution process as its own load information, and a management step of managing the load information notified in this notification step as transmission process information And when a client requests a connection to the video server system, it refers to the transmission process information managed in these management steps, assigns the video stream transmission process with the lightest load state, and instructs the connection. Video stream including instructional steps It was recorded load balancing program sending process.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION (A) First Embodiment Hereinafter, a first embodiment of an apparatus to which a load distribution method for a video stream transmission process according to the present invention is applied will be described in detail with reference to the drawings.

(A-1) Configuration of the First Embodiment FIG. 1 is a block diagram showing the configuration of the load balancer of the video stream transmission process of the first embodiment. Figure 1
In the first embodiment shown in FIG. 1, the configuration and operation will be described by taking the video server system 11 as an example.

The first embodiment is not limited to the video server system 11, but can be applied to any video server system composed of a plurality of computers, for example.

Further, in the computer referred to herein, one or more "video stream transmission process" for transmitting a video signal to the client (user) is activated, and the client (user) accepts a request. There is one in which the "user request receiving / load balancing process" for selecting / deciding the video stream transmitting process to be allocated to is activated. The computer is also connected to a disk device storing video data via a storage area network.

The "video stream transmitting process" and the "user request receiving / load balancing process" may be configured to exist on a plurality of computers, or an arbitrary process may be performed on a single computer. It may be configured to exist in. Here, it is assumed that the “video stream transmission process” and the “user request reception / load distribution process” are activated on different computers.

The video server system 11 is connected to each of the clients 31 to 34 via the network 21. In addition, the video server system 11
The computer 41 to 44 and the disks 51 and 52 are included, and the computers 41 to 44 and the disks 51 and 52 as disk devices are mutually connected by a storage area network 61.

Further, the computers 41, 42 and 43 are respectively connected to the video stream transmission processes 71, 72 and 73.
Are activated respectively and adopt a parallel process configuration.
On the computer 44, the user request receiving / load balancing process 81 is started.

Video stream transmission process 71, 7
2, 73 transmit a video stream to the clients 31 to 34 connected to the video server system 11 via the network 21.

FIG. 2 is a functional block diagram showing the functional contents of the user request receiving / load balancing process 81 activated by the computer 44. The user request reception / load distribution process 81 includes a user request reception processing unit 811 that receives a request from a client (or a user) and a parallel process information management unit 812 that receives a process information notification from the video stream transmission process.

Next, the parallel process information management section 812 will be described with reference to FIG. The parallel process information management unit 812 sends process information notifications from all the video stream transmission processes 71, 72, 73 existing on the video server system to the storage area network 6.
1 or periodically received via a network (not shown), and transmission process information 81221 and 8122, respectively.
2, 81223. There is one piece of information in the transmission process information for each video stream transmission process, and all the information is the transmission process information list 8
It is managed by 121.

FIG. 4 shows a transmission process information list 8121.
6 is a data configuration diagram of transmission process information 81221 managed by FIG. Also, transmission process information 81222, 81
223 also has a similar data structure.

Transmission process information 81221 shown in FIG.
Is the sending process identifier, sending process access information,
Process status, number of connected users, CPU load, network load, disk access load, bandwidth capacity (maximum capacity)
And bandwidth capacity (used capacity).

Of these information, the process status, number of connected users, CPU load, network load, disk access load, bandwidth capacity (maximum capacity), bandwidth capacity (used capacity) are notified from the video stream transmission process. By receiving it, the information is always updated. A detailed description of each of these data is shown in a tabular form in FIG.

Referring again to FIG. 2, the user request reception processing unit 811 sends a video to the parallel process information management unit 812 when a request is made from the client (user) via the network 21. Requests allocation of stream transmission process. Parallel process information management unit 8
12, the transmission process information list 8121 shown in FIG.
Of each transmission process information 81221, 81222, 812
The optimum video stream transmission process is determined from 23 and returned to the user request reception processing unit 811. The user request reception processing unit 811 notifies the client of information for accessing the determined video stream transmission process.

FIG. 5 shows the video stream transmission process 7.
2 is a functional block configuration diagram showing the function of 1. FIG. Note that the video stream transmission processes 72 and 73 have the same configuration and operation, and therefore, here, the video stream transmission process 7
1 will be described.

In FIG. 5, the video stream transmission process 71 includes a video operation request reception processing unit 711, a video stream transmission processing unit 712, an own process information notification unit 713, and a video data reading unit 714.

First, the video operation request reception processing unit 711.
Upon receiving a video operation request from the client (user), the video data reading unit 714 reads the video data from the disks 51 and 52 according to the operation request, and the video stream transmission processing unit 712 sends the video stream to the client. Is sent.

At this time, the own process information notifying unit 713 measures the CPU load, network load, and disk access load on the computer, and at the same time, determines the number of users connected to itself and the video stream being transmitted. The used capacity is calculated and notified to the user request reception / load distribution process as process information. The process in the own process information notification unit 713 is performed at a predetermined time interval (for example, every 10 seconds).

(A-2) Operation of the First Embodiment Next, the operation of the load balancer of the video stream transmission process of the first embodiment will be described.

The operation of the video server system 11 will be described below in accordance with the processing procedure with reference to the flowchart shown in FIG.

First, the video stream transmission processes 71, 72, 73 on the video server system periodically
For example, the load information of itself is measured at a predetermined time interval (for example, every 10 seconds), and the user request reception / load distribution process 8 is performed.
1 is notified (step S11).

The user request reception / load distribution process 81 that has received the notification updates the data of the transmission process information corresponding to the video stream transmission process of the notification source based on the notified load information (step S13).

For example, referring to FIG. 3, when the video stream transmission process 71 notifies the load information, the parallel process information management unit 812 of the user request reception / load distribution process 81 receives the load information, and the parallel process information management unit 812. Is the notification source video stream transmission process 71
The data on the transmission process information 81221 corresponding to is updated based on the notified information.

By this series of operations, user request reception /
Parallel process information management unit 812 of the load balancing process 81
The latest transmission process information can be always managed for each video stream transmission process.

The parallel process information management unit 812 at this time
FIG. 8 shows the operation flow of the above. First, when the process information notification is received in step S31, the process proceeds to step S33,
The parallel process information management unit 812 of the user request reception / load distribution process 81 updates the data on the transmission process information corresponding to the video stream transmission process of the notification source with the value included in the notified information.

Next, with reference to FIG. 7, an operation example of the video server system 11 when a user uses a video service through a client will be described.

First, the user requests the video server system 11 to access the server through each client (step S15). First, the user request reception / load distribution process 81 causes the video stream transmission processes 71, 72, 73. The process with the lightest load is determined from among these (step S17), and the access information of this process is returned to the client as the access request source (step S19). Next, the client connects to the video stream transmission process based on this access information, requests video operation (step S21), reads the video data from the disc (step S23), and receives the transmitted video stream (step S25). , Use video services.

Referring to FIG. 7, for example, when the client 31 shown in FIGS. 1 and 2 makes a server access request to the video server system 11 via the network 21 (step S15), the request is stored on the computer 44. The user request reception processing unit 811 of the user request reception / load distribution process 81 receives the request. Upon receiving the request, the user request reception processing unit 811 requests the parallel process information management unit 812 to allocate the video stream transmission process.

The parallel process information management unit 812 has its own video stream transmission processes 71, 72, 73.
Of each of the transmission process information are compared to determine the video stream transmission process with the lightest load (step S1).
7). The access information of the determined video stream transmission process is returned to the user request reception processing unit 811 through the parallel process information management unit 812, and the user request reception processing unit 811 notifies the client 31 of this access information (step S19).

For example, when the parallel process information management unit 812 determines the video stream transmission process 72, the access information for this video stream transmission process 72 is returned from the user request reception processing unit 811 to the client 31, and the client 31 accesses this access. Based on the information, the video stream transmission process 72 on the computer 42 is connected to perform the video operation (step S2).
1, 23, 25).

Next, the processing procedure for video stream transmission process allocation will be described with reference to FIG.

When the client 31 makes a server access request to the video server system 11, the user request reception processing unit 811 that has received the request requests the parallel process information management unit 812 to allocate a video stream transmission process. (Step S41).

If it is determined in step S43 that there is a process in a normal state, step S45
Proceed to.

The allocation of the video stream transmission process of the parallel process information management unit 812 is performed by copying the transmission process information list 8131 shown in FIG. 3 (step S4).
5), each transmission process information 8 about the copied list
This is performed by sorting the data 1321 to 81323 based on the load comparison condition (step S47), and determining the process with the lightest load among them.

Subsequently, in step S49, it is determined that the allocation is normal, and the access information of the transmission process information at the head of the sorted list is notified to the user request reception processing unit 811.
The process ends.

If it is determined in step S43 that there is no process in the normal state, the process advances to step S51 to notify the user reception processing unit 811 that there is no process that can be allocated as an allocation error. The process ends.

The parallel process information management unit 812 has a pattern load comparison condition. That is, the load comparison condition 1 is one in which any one of the CPU load, the network load, the disk access load, and the capacity utilization rate of the video stream transmission process is extracted, and this is regarded as a process with a large load. .

The load comparison condition 2 is "CPU load>
The load values are compared in the order of “network load> disk access load> capacity utilization rate”, and the process with the higher load value is regarded as the process with the higher load.

Next, the load comparison condition 1 will be described in detail with reference to FIG.

First, in step S61, regarding the two pieces of process information to be compared, the one that is ahead of the list is A and the one that is behind the list is B. Next, in step S63, regarding items other than the number of connected users, the larger the value, the higher the load. Therefore, the total load value is calculated using the following calculated values.

[0061] Total load value = {L1} + {L2} + {L3} + {L4} However, {L1}; {CPU load cubed} {L2}; {Network load cubed} {L3}; {Disk access load cubed} {L4}; {Capacity usage cubed} And

Next, in step S65, the total load values are compared, and if A> B, the process advances to step S69 to replace the positions of A and B on the list, and then the process ends. Also A <
If it is B, the process is ended as it is. If A = B, the process proceeds to step S67 to further compare the number of connected users. If A> B, the process proceeds to step S69 and A is displayed on the list.
After replacing the positions of B and B, the process ends. If A = B or A <B, the process is terminated.

Next, the load comparison condition 2 will be described in detail with reference to FIG.

First, in step S71, CPU loads are compared, and if A> B, the process proceeds to step S81, where the positions of A and B are replaced on the list, and then the process ends. Also A <
If it is B, the process is terminated, and if A = B, the process proceeds to step S73.

Subsequently, in step S73, the network loads are compared, and if A> B, the process proceeds to step S81, where the positions of A and B are replaced on the list, and the process ends.
If A <B, the process is terminated, and if A = B, the process proceeds to step S75.

Subsequently, in step S75, the disk access loads are compared, and if A> B, the process proceeds to step S81, where the positions of A and B are replaced on the list, and the process ends. If A <B, the process is terminated as it is, and A = B
If so, the process proceeds to step S77.

Subsequently, in step S77, the capacity utilization rates are compared, and if A> B, the process proceeds to step S81, where the positions of A and B are replaced on the list, and the process ends. Also A
If <B, the process is terminated, and if A = B, the process proceeds to step S79.

Subsequently, in step S79, the number of connected users is compared. If A> B, the process proceeds to step S81, where the positions of A and B are replaced on the list, and the process is terminated. If A = B or A <B, the process is terminated.

In this way, the parallel process information management unit 812 sorts the copy of the transmission process information list according to the load comparison condition 1 or the load comparison condition 2 depending on the setting of the video server system. This setting is
The administrator of the video server system can judge the load characteristics of the system and set either condition.

(A-3) Effect of the First Embodiment According to the first embodiment, by assigning the process with the lightest load among all the video stream transmission processes to the request of the client, In addition to preventing the concentration of the load on one process, the load items other than the CPU load can be distributed about the network load, the disk access load, and the usage rate of the transmission bit rate with respect to the maximum capacity.

Further, a mechanism is adopted in which the load information is periodically notified from each video stream transmission process, and an abnormality in the video stream transmission process is detected early by not receiving the user request reception / load distribution process. be able to. This makes it possible to prevent a video stream transmission process that is not operating normally from being assigned to the client, thereby improving the reliability of the video server system.

By disposing a plurality of load comparison conditions, it is possible to realize load distribution according to the load characteristics of each video server system.

(B) Second Embodiment Next, a second embodiment of a load distribution method and apparatus for a video stream transmission process according to the present invention will be described in detail with reference to the drawings.

(B-1) Configuration of Second Embodiment Since the configuration of the second embodiment is the same as that of the first embodiment, FIGS. 1 to 6 of the first embodiment will be used.

(B-2) Operation of Second Embodiment Hereinafter, an operation example of the second embodiment is substantially the same as the operation example of the first embodiment shown in FIG.

Here, for example, in FIG. 3 and FIG. 4, when the video stream transmission process 71 notifies the load information,
The parallel process information management unit 812 of the user request reception / load distribution process 81 receives this, and the parallel process information management unit 812 notifies each data information on the transmission process information 81221 corresponding to the video stream transmission process 71 of the notification source and the notification. Compare the information provided.

The operation of the parallel process information management unit 812 will be described below with reference to FIG.

First, the process information notification is received (step S91). Next, the number of connected users on the transmission process information 81221 and the information notified from the video stream transmission process is compared to confirm whether or not the number of connected users has increased (step S93). If there is no increase in the number of connected users, the process proceeds to step S95, and it is confirmed whether the values of the CPU load, the network load, and the disk access load have changed. If these values have changed,
It is assumed that the user has stopped operating the video or is performing a special operation.

For example, when the load is reduced, the CPU load, network load, and disk access load values on the transmission process information 81221 are not updated,
The process ends (step S99). If the load is high, C on the transmission process information 81221
The values of the PU load, the network load, and the disk access load are calculated as intermediate values among them in the notified information, updated, and the processing ends (step S97).

When it is confirmed in step S93 that the number of connected users is increasing, and in step S95, there is no change in the values of the CPU load, network load, and disk access load on the transmission process information 81221. Then, the process proceeds to step S101, the value on the transmission process information is updated with the value set in the notified information, and the process ends.

(B-3) Effects of the Second Embodiment In the second embodiment, the user accidentally suspends the video operation or performs a special operation such as fast-forwarding which is considered to be heavy. And even if the load changes temporarily,
The optimal computer can be assigned using the previous load information.

(C) Third Embodiment Next, a third embodiment of a load distribution method and apparatus for a video stream transmission process according to the present invention will be described in detail with reference to the drawings.

(C-1) Configuration of Third Embodiment Since the configuration of the third embodiment is the same as that of the first and second embodiments, FIGS. 1 to 6 of the first embodiment will be described. To use.

(C-2) Operation of the third embodiment Hereinafter, the operation example of the third embodiment will be described with reference to the first and the second operations shown in FIG.
This is the same as the operation example of the second embodiment.

Here, for example, in FIG. 3 and FIG. 4, when the video stream transmission process 71 notifies the load information,
The parallel process information management unit 812 of the user request reception / load distribution process 81 receives this, and the parallel process information management unit 812 notifies each data information on the transmission process information 81221 corresponding to the video stream transmission process 71 of the notification source and the notification. Compare the information provided.

Referring to FIG. 13, first, the comparison is made by comparing the number of connected users on the transmission process information 81221 and the information notified from the video stream transmission process (step S113) to determine whether the number of connected users has increased. To confirm. The second operation flow is when there is no increase in the number of connected users.
12 shown in the embodiment of FIG.

In the second embodiment, when the number of connected users increases, the parallel process information management unit 812 uses the notified information value as it is as the transmission process information 81221.
Update to the above data. At this time, when the user has not started the video operation, there may be a difference between the actual computer status and the value of the notified load information.

Therefore, in the third embodiment, when the number of connected users increases, how the load changes is statistically calculated and the processing capacity of the corresponding computer is determined.

For example, when it is determined in step S113 that the number of connected users has increased, the CPU load on the transmission process information 81221, the network load,
Recalculate the disk access load correction value (step S
115), using the correction value obtained by this recalculation, CP
The increase is corrected for the U load, the network load, and the disk access load (step S117).

Next, the value of the load information set in the notified information is compared, and for example, when the load is reduced, the CP on the transmission process information 81221 is compared.
The U load, network load, and disk access load are not updated (step S123). If the load is high, the transmission process information 81221 and the CPU
The load, the network load, and the disk access load are updated by taking an intermediate value between these pieces of information set in the notified information (step S121). If there is no change, the value in the transmission process information is updated to the notified information by the set value (step S12).
5).

(C-3) Effects of Third Embodiment In the third embodiment, computers can be allocated more effectively by statistically operating the load information.

In the first embodiment described above, an example using a video server system in which three computers in which a video stream transmission process is activated has been described, but the present invention is not limited to this. Without being provided, for example, if a computer in which two or more video stream transmission processes are activated is installed, it can be applied to the load distribution method and apparatus of the video stream transmission process of the present invention.

Further, the load balancing program of the video stream transmission process described above can be distributed more easily by an arbitrary communication medium including a wireless line, a telephone line, the Internet, etc. and a recording medium recording the load balancing program. You can

[0094]

As described above, according to the load distribution method and apparatus of the video stream transmission process, the load distribution program, and the recording medium on which the program is recorded according to the present invention, various loads are measured, and the measurement result is measured by itself. Since the load request information is notified to the user request reception / load distribution process, it is easy to manage the load imbalance, and it is possible to prevent concentration of the load in advance.

Further, since the process having the lightest load is assigned to the request of the client from all the video stream transmission processes, it is possible to prevent the concentration of the load on one process. it can.

Further, as the load, in addition to the CPU load, the network load, the disk access load, and the usage rate of the transmission bit rate with respect to the maximum capacity can be dispersed, so that even if the load temporarily fluctuates. You can assign the best computer.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a video server system according to a first embodiment.

FIG. 2 is a functional block diagram of a user request reception and load distribution process.

FIG. 3 is a diagram showing data correlation in a parallel process information management unit.

FIG. 4 is a diagram showing a data structure of transmission process information.

FIG. 5 is a functional block diagram of a video stream transmission process.

FIG. 6 is a diagram illustrating data content of transmission process information.

FIG. 7 is a flowchart for explaining the operation of the video server system and the service utilization procedure.

FIG. 8 is a flowchart showing a processing procedure of information notification reception from a video stream transmission process.

FIG. 9 is a flowchart illustrating a processing procedure when allocating a video stream transmission process.

FIG. 10 is a flowchart showing a comparison processing procedure at the time of load comparison of transmission process information.

FIG. 11 is a flowchart showing a comparison processing procedure at the time of load comparison of transmission process information.

FIG. 12 is a flowchart showing a processing procedure of information notification reception from the video stream transmission process according to the second embodiment.

FIG. 13 is a flowchart showing a processing procedure of information notification reception from the video stream transmission process according to the third embodiment.

[Explanation of symbols]

11 ... Video server system, 21 ... Network, 3
1, 32, 33, 34 ... Clients, 41, 42, 4
3, 44 ... Computer, 51, 52 ... Disk, 61
… Storage area network, 71, 72, 73…
Video stream transmission process, 81 ... User request reception / load distribution process.

Claims (8)

[Claims] 1. One or more video stream transmission processes for transmitting a video signal to a client on a plurality of computers connected via a network, and a process for receiving the request from the client and transmitting the video stream transmission process to the client. A load distribution method of a video stream transmission process when a user request reception / load distribution process to be allocated is started, wherein the video stream transmission process is a CPU load generated by a processing operation according to a video operation request from a client, At least one of network load, disk access load, used capacity of playback bit rate, and number of connected users is measured, and these are notified to the user request reception / load distribution process as own load information. And bidet Load balancing method of the stream transmission process. 2. One or more video stream transmission processes for transmitting a video signal to a client on a plurality of computers connected via a network, and receiving the request from the client to allow the video stream transmission process to the client. A load balancing method of a video stream transmitting process when a user request receiving / load balancing process to be allocated is started, wherein the user request receiving / load balancing process transmits load information notified from each video stream transmitting process. It is managed as information, and when a client requests a connection to a video server system, it refers to these transmission process information and allocates the video stream transmission process with the lightest load state to instruct the connection. Video stream Load balancing method of non-transmission process. 3. The value of any one of CPU load, network load, disk access load, and capacity utilization rate stands out as a condition for determining the video stream transmission process whose load state in the user request reception / load distribution process is the lightest. Of the conditions under which it is considered that the load is large, and the load values are compared in the order of CPU load, network load, disk access load, and capacity utilization rate. 3. The load distribution method for a video stream transmission process according to claim 2, wherein any one of them is included and these conditions can be selected. 4. The load value of the video stream transmission process is calculated on the assumption of a change in load due to special playback such as pause or fast-forward of video operation. A load balancing method for the described video stream transmission process. 5. The method according to claim 1, wherein an increase in load due to an increase in the number of user connections to the video stream transmission process is predicted, and the predicted value is used for calculating the load value of the video stream transmission process. 2. A load distribution method for a video stream transmission process according to any one of 1. 6. One or more video stream transmission processes for transmitting a video signal to a client on a plurality of computers connected via a network, and the video stream transmission process for receiving the request from the client to the client. A load balancer for the video stream transmission process when the user request reception / load distribution process to be allocated is started, and the CPU load, network load, disk access load generated by the processing operation according to the video operation request from the client, Measuring means for measuring at least one of the used capacity of the reproduction bit rate and the number of connected users, and a notification for notifying the user request reception / load distribution process of the load measured by this measuring means as its own load information. Means and said load to be notified When the client requests a connection to the video server system, the management means that manages the information as transmission process information, and refers to these transmission process information, allocates the video stream transmission process with the lightest load state and makes the connection. A load balancer for a video stream transmission process, comprising: an instruction means for instructing. 7. One or more video stream transmission processes for transmitting a video signal to a client on a plurality of computers connected via a network, and receiving the request from the client, the video stream transmission process to the client. A load distribution program for the video stream transmission process when the user request reception / load distribution process to be allocated is started, and the CPU load, network load, disk access load generated by the processing operation according to the video operation request from the client, A measurement step for measuring at least one of the used capacity of the reproduction bit rate and the number of connected users, and a notification for notifying the load measured in this measurement step to the user request reception / load distribution process as its own load information Steps, With reference to the management step of managing the load information notified in this notification step as transmission process information and the transmission process information managed in these management steps when the client requests a connection to the video server system, A load balancing program for a video stream transmission process, comprising: assigning a video stream transmission process having the lightest load state and instructing a connection. 8. One or more video stream transmission processes for transmitting a video signal to a client on a plurality of computers connected via a network, and accepting a request from the client to cause the video stream transmission process to the client. A recording medium in which a load balancing program of a video stream transmitting process when the user request receiving / load balancing process is activated is recorded, and is a CPU load and a network load generated by a processing operation according to a video operation request from a client , A disk access load, a playback bit rate used capacity, and a measurement step of measuring at least one of the number of connected users, and the load measured in this measurement step as user's load information and user request reception / load distribution Notify the process The notification step, the management step that manages the load information notified in this notification step as transmission process information, and the transmission process information that is managed in these management steps when the client requests a connection to the video server system A recording medium having a load distribution program of a video stream transmission process recorded therein, which has an instruction step of allocating a video stream transmission process having the lightest load state and instructing connection.