Job execution processor changing method and system, for load distribution among processors

• US 5,870,604 A
• Filed: 07/10/1995
• Issued: 02/09/1999
• Est. Priority Date: 07/14/1994
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamagishi, Tadashi
• Primary Examiner(s): Banankhah, Majid A.
• Application Number:
  US08/500,205
• Time in Patent Office: 1,310 Days
• Field of Search: 395/650, 395/700, 395/675, 395/672, 395/670, 364/200
• US Class Current: 718/105
• CPC Class Codes: G06F 9/5088 involving task migration

Abstract

In a system including a plurality of processors for executing jobs, an execution processor of which the number of jobs waiting for execution is large is changed to a low-loaded processor so that distribution of the load among the processors is achieved. When jobs are inputted to a processor, a job scheduler stores job information in a job status table and sequentially executed the jobs. Processor monitor control units mutually communicate the load status of the processors by using the communication control unit, and store the status in the operation status table. A job execution processor change control unit changes the jobs waiting for execution in the job status table to the low-loaded processor in the operation status table. The job transfer control unit transfers the jobs to the job execution processor.

Claims

1. In a system including a plurality of processors for executing jobs, a job scheduler for controlling the sequence of executing said jobs, a communication control unit for carrying out data transmission between said plurality of processors, and job transfer means for carrying out transfer of jobs between said plurality of processors,

a method for changing a job execution processor, including the steps of:

a processor monitoring step for mutually monitoring a load status of each of said plurality of processors;

a job execution processor determining step for determining a job execution processor by comparing the load statuses of all of said plurality of processors when a job is inputted to the system, wherein said step of comparing the load statuses of all of said plurality of processors is performed by referring to an operation status table that stores the load statuses of all of said plurality of processors; and

a job execution processor changing step for mutually changing a job execution processor that has already been determined for executing a job queued for execution by one of said plurality of processors, by comparing the load statuses of the processors stored in the operation status table, at regular intervals.

2. A method for changing a job execution processor according to claim 1, wherein said step for changing a job execution processor further comprises a step for transmitting a request for changing a job execution processor to a higher-loaded second processor when there has been no job to be executed by a job scheduler of a first processor, and transmitting a job from the second processor to the first processor in response to the request.

3. A method for changing a job execution processor according to claim 1, wherein said step for changing a job execution processor further comprises a step for changing a job execution processor in a second processor when a request for changing a job execution processor has been received from a first processor.

4. A method for changing a job execution processor according to claim 1, wherein said step for changing a job execution processor further comprises a step in which each processor checks job execution waiting numbers of all processors stored on each operation status table at regular intervals, and a step for changing a job execution processor of a job waiting for execution by a first processor to a second processor capable of executing the job when said first processor is highly loaded and when the second processor has no waiting job.

5. A method for changing a job execution processor according to claim 1, wherein said load to be monitored by said processor monitoring step is the number of jobs waiting for execution by said processors.

6. A method for changing a job execution processor according to claim 1, wherein said load to be monitored by said processor monitoring step is a CPU using rate by said processors.

7. A method for changing a job execution processor according to claim 1, wherein said load to be monitored by said processor monitoring step is an I/O unit using rate by said processors.

8. A method for changing a job execution processor according to claim 1, wherein said load to be monitored by said processor monitoring step is a memory using rate by said processors.

19. A method for changing a job execution processor according to claim 1, wherein each of said plurality of processors has an operation status table that stores the load statuses of all of said plurality of processors, and wherein said step of comparing the load statuses of all of said plurality of processors is performed by referring to the operation status table contained in the processor performing the load status comparison.

20. A method for changing a job execution processor according to claim 19, wherein each of said plurality of processors further contains a job status table that stores all jobs being executed or queued for all of said plurality of processors, and executable processors for each job stored in said job status table.

9. In a system including a plurality of processors for executing jobs, a job scheduler for controlling the sequence of executing said jobs, a communication control unit for carrying out data transmission between said plurality of processors, and job transfer means for carrying out transfer of jobs between said plurality of processors,

a system for changing a job execution processor, comprising:

processor monitoring means for mutually monitoring a load status for each of said plurality of processors;

job execution processor determining means for determining a job execution processor by comparing the load statuses of all of said plurality of processors when a job is inputted to the system, wherein said step of comparing the load statuses of all of said plurality of processors is performed by referring to an operation status table that stores the load statuses of all of said plurality of processors; and

job execution processor changing means for mutually changing a job execution processor that has already been determined for executing a job queued for execution by one of said plurality of processors, by comparing the load statuses of the processors stored in the operation status table, at regular intervals.

10. A system for changing a job execution processor according to claim 9, wherein said means for changing a job execution processor further comprises means for transmitting a request for changing a job execution processor to a higher-loaded second processor when there has been no job to be executed by a job scheduler of a first processor, and for transmitting a job from the second processor to the first processor in response to the request.

11. A system for changing a job execution processor according to claim 9, wherein said means for changing a job execution processor further comprises means for changing a job execution processor in a second processor when a request for changing a job execution processor has been received from a first processor.

12. A system for changing a job execution processor according to claim 9, wherein said means for changing a job execution processor further comprises means, in each processor, for checking job execution waiting numbers of all processors stored on each operation status table at regular intervals, and means for changing a job execution processor of a job waiting for execution by a first processor to a second processor when said first processor is highly loaded.

13. A system for changing a job execution processor according to claim 9, wherein said load to be monitored by said processor monitoring means is the number of jobs waiting for execution by said processors.

14. A system for changing a job execution processor according to claim 9, wherein said load to be monitored by said processor monitoring means is a CPU using rate by said processors.

15. A system for changing a job execution processor according to claim 9, wherein said load to be monitored by said processor monitoring means is an I/O unit using rate by said processors.

16. A system for changing a job execution processor according to claim 9, wherein said load to be monitored by said processor monitoring means is a memory using rate by said processors.

21. A system for changing a job execution processor according to claim 9, wherein each of said plurality of processors has an operation status table that stores the load statuses of all of said plurality of processors, and wherein said job execution processor determining means compares the load status of all of said plurality of processors by referring to the operation status table contained in the processor performing the load status comparison.

22. A system for changing a job execution processor according to claim 21, wherein each of said plurality of processors further contains a job status table that stores all jobs being executed or queued for all of said plurality of processors, and executable processors for each job stored in said job status table.

17. In a system including a plurality of processors for executing jobs, the plurality of processors being connected to one another, a method for changing a job execution processor, including the steps, executed by respective processors, of:

monitoring own processor load status, and monitoring a load status of each of the other processors by receiving load data from each of the other processors;

storing the load statuses of all of said plurality of processors in an operation status table, the operation status table being updated at regular intervals;

determining a job execution processor by comparing the load statuses of all of said plurality of processors when a job is inputted to the system, wherein said step of comparing the load statuses of all of said plurality of processors is performed by referring to said operation status table;

when there is no waiting job in own processor, sending a job transfer request to another of said plurality of processors having the heaviest load by referring to the operation status table, receiving a job transferred from the processor to which the job transfer request was sent, and executing the job; and

when there are waiting jobs in said own processor, receiving a job transfer request from another of said plurality of processors, selecting one of the waiting jobs which can be executed by the job transfer requesting processor, and transferring the selected job to the processor from which the job transfer request was received.

23. A method for changing a job execution processor according to claim 17, wherein each of said plurality of processors has an operation status table that stores the load statuses of all of said plurality of processors, and wherein said step of comparing the load statuses of all of said plurality of processors is performed by referring to the operation status table contained in the processor performing the load status comparison.

24. A method for changing a job execution processor according to claim 23, wherein each of said plurality of processors further contains a job status table that stores all jobs being executed or waiting for all of said plurality of processors, and executable processors for each job stored in said job status table.

18. A system including a plurality of processors for executing jobs, the processors being connected to one another, for distributing load over the processors, each processor including:

a communication control unit for sending/receiving data to/from other processors;

a processor monitoring unit for monitoring own processor load status and monitoring a load status of each of the other of said plurality of processors by receiving load data from the other of said plurality of processors via the communication control unit, and for storing the load statuses of all of said plurality of processors in an operation status table, the operation status table being updated at regular intervals;

a job execution processor determining unit for determining a job execution processor executing each waiting job by comparing the load statuses of all of said plurality of processors when a job is inputted to the system and when there are waiting jobs in own processor, wherein said step of comparing the load statuses of all of said plurality of processors is performed by referring to the operation status table; and

a job execution processor changing unit for sending a job transfer request to a heaviest-loaded one of the other processors via the communication control unit when there is no waiting job in said own processor; and

a job transfer control unit for transferring a job that is already awaiting execution by said heaviest-loaded one of the other processors to another processor via the communication control unit when receiving the job transfer request, the waiting job being determined to be executed by the job transfer requesting processor by the job execution processor changing unit, and for receiving the transferred job via the communication control unit.

25. A system according to claim 18, wherein each of said plurality of processors has an operation status table that stores the load statuses of all of said plurality of processors, and wherein said job execution processor determining unit compares the load statuses of all of said plurality of processors by referring to the operation status table contained in the processor performing the load status comparison.

26. A system according to claim 25, wherein each of said plurality of processors further contains a job status table that stores all jobs being executed or waiting for all of said plurality of processors, and executable processors for each job stored in said job status table.