MANAGING THREAD EXECUTION IN A MULTITASKING COMPUTING ENVIRONMENT

• US 20170109196A1
• Filed: 10/16/2015
• Published: 04/20/2017
• Est. Priority Date: 10/16/2015
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bailey, Christopher N., Deakin, Oliver M.
• Granted Patent: US 10,169,078 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 9/485 Task life-cycle, e.g. stopping, restarting, resuming execution G06F9/4881 takes precedence
• CPC Class Codes: G06F 9/5038 considering the execution order of a plurality of tasks, e.g. taking priority or time dependency constraints into consideration scheduling strategies G06F9/4881 and subgroups
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms

Abstract

A thread in a computing system is processed for execution of instructions to perform an action. The action is one of the following: accessing a shared resource or executing a critical section of code. A schedule of the thread is managed. The management prevents suspension of the thread during execution of the action.

Claims

1. A method for managing thread execution, the method comprising:

processing, by one or more computer processors, a thread in a computing system for execution of instructions to perform an action, wherein the action is one of the following;

accessing a shared resource or executing a critical section of code; and

managing, by one or more computer processors, a schedule of the thread, wherein the managing prevents suspension of the thread during execution of the action.

2. The method of claim 1, wherein managing the schedule of the thread comprises:

scheduling, by one or more computer processors, the thread for execution of the instructions to perform the action;

receiving, by one or more computer processors, a request to deschedule the thread, wherein the request is made in response to determining that a contending thread is attempting to access the shared resource;

responsive to receiving the request to deschedule the thread, scheduling, by one or more computer processors, the thread to complete execution of the instructions to access to the shared resource; and

responsive to scheduling the thread to complete execution, determining, by one or more computer processors, processor usage debt accumulated by the thread, wherein the processor usage debt comprises an amount of time for which the thread is executing while the thread has both insufficient processor usage allowance to continue execution and is accessing the shared resource.

3. The method of claim 2, further comprising:

responsive to determining that the thread has completed execution of the instructions to perform the action, suspending, by one or more computer processors, the thread for an amount of time equal to the determined processor usage debt accumulated by the thread.

4. The method of claim 1, wherein managing the schedule of the thread comprises:

scheduling, by one or more computer processors, the thread for execution of the instructions to perform the action;

receiving, by one or more computer processors, a request to deschedule the thread, wherein the request is made in response to determining that the thread has insufficient processor usage allowance to continue execution;

responsive to receiving a request to deschedule the thread, scheduling, by one or more computer processors, the thread to complete execution of the instructions to execute the critical section of code; and

responsive to scheduling the thread to complete execution, determining, by one or more computer processors, processor usage debt accumulated by the thread, wherein the processor usage debt comprises an amount of time for which the thread is executing while the thread has both insufficient processor usage allowance to continue execution and is executing the critical section of code.

5. The method of claim 4, further comprising:

responsive to determining that the thread has completed execution of the instructions to perform the action, suspending, by one or more computer processors, the thread for an amount of time equal to the determined processor usage debt accumulated by the thread.

6. The method of claim 1, wherein managing the schedule of the thread comprises:

before scheduling the thread for execution of the instructions to perform the action, determining, by one or more computer processors, if the thread has a first processor usage allowance that is sufficient to complete execution of the instructions to perform the action;

responsive to determining that the thread has the first processor usage allowance that is sufficient, scheduling, by one or more computer processors, the thread to complete execution of the instructions to perform the action; and

responsive to determining that the thread has the first processor usage allowance that is not sufficient, suspending, by one or more computer processors, the thread until the thread has sufficient processor usage allowance.

7. The method of claim 6, wherein determining if the thread has a sufficient first processor usage allowance comprises:

predicting, by one or more computer processors, a second processor usage allowance for the thread based on a processor usage allowance previously determined for the thread or a similar thread; and

comparing, by one or more computer processors, the first processor usage allowance of the thread with the predicted second processor usage allowance of the thread during execution of the instructions to perform the action.

8. A computer program product for managing thread execution, the computer program product comprising:

one or more computer readable storage media; and

program instructions stored on the one or more computer readable storage media, the program instructions comprising;

program instructions to process a thread in a computing system for execution of instructions to perform an action, wherein the action is one of the following;

accessing a shared resource or executing a critical section of code; and

program instructions to manage a schedule of the thread, wherein the managing prevents suspension of the thread during execution of the action.

9. The computer program product of claim 8, wherein the program instructions to manage the schedule of the thread comprise:

program instructions to schedule the thread for execution of the instructions to perform the action;

program instructions to receive a request to deschedule the thread, wherein the request is made in response to determining that a contending thread is attempting to access the shared resource;

program instructions, responsive to receiving the request to deschedule the thread, to schedule the thread to complete execution of the instructions to access to the shared resource; and

program instructions, responsive to scheduling the thread to complete execution, to determine processor usage debt accumulated by the thread, wherein the processor usage debt comprises an amount of time for which the thread is executing while the thread has both insufficient processor usage allowance to continue execution and is accessing the shared resource.

10. The computer program product of claim 9, further comprising program instructions, stored on the one or more computer readable storage media, to:

responsive to determining that the thread has completed execution of the instructions to perform the action, suspend the thread for an amount of time equal to the determined processor usage debt accumulated by the thread.

11. The computer program product of claim 8, wherein the program instructions to manage the schedule of the thread comprise:

program instructions to schedule the thread for execution of the instructions to perform the action;

program instructions to receive a request to deschedule the thread, wherein the request is made in response to determining that the thread has insufficient processor usage allowance to continue execution;

program instructions, responsive to receiving a request to deschedule the thread, to schedule the thread to complete execution of the instructions to execute the critical section of code; and

program instructions, responsive to scheduling the thread to complete execution, to determine processor usage debt accumulated by the thread, wherein the processor usage debt comprises an amount of time for which the thread is executing while the thread has both insufficient processor usage allowance to continue execution and is executing the critical section of code.

12. The computer program product of claim 11, further comprising program instructions, stored on the one or more computer readable storage media, to:

responsive to determining that the thread has completed execution of the instructions to perform the action, suspend the thread for an amount of time equal to the determined processor usage debt accumulated by the thread.

13. The computer program product of claim 8, wherein the program instructions to manage the schedule of the thread comprise:

program instructions, before scheduling the thread for execution of the instructions to perform the action, to determine if the thread has a first processor usage allowance that is sufficient to complete execution of the instructions to perform the action;

program instructions, responsive to determining that the thread has the first processor usage allowance that is sufficient, to schedule the thread to complete execution of the instructions to perform the action; and

program instructions, responsive to determining that the thread has the first processor usage allowance that is not sufficient, to suspend the thread until the thread has sufficient processor usage allowance.

14. The computer program product of claim 13, wherein the program instructions to determine if the thread has sufficient processor usage allowance comprise:

program instructions to predict a second processor usage allowance for the thread based on a processor usage allowance previously determined for the thread or a similar thread; and

program instructions to compare the first processor usage allowance of the thread with the predicted processor usage of the thread during execution of the instructions to perform the action.

15. A computer system for managing thread execution, the computer system comprising:

one or more computer processors;

one or more computer readable storage media; and

program instructions, stored on the one or more computer readable storage media, for execution by at least one of the one or more computer processors, the program instructions comprising;

program instructions to process a thread in a computing system for execution of instructions to perform an action, wherein the action is one of the following;

accessing a shared resource or executing a critical section of code; and

program instructions to manage a schedule of the thread, wherein the managing prevents suspension of the thread during execution of the action.

16. The computer system of claim 15, wherein the program instructions to manage the schedule of the thread comprise:

program instructions to schedule the thread for execution of the instructions to perform the action;

program instructions to receive a request to deschedule the thread, wherein the request is made in response to determining that a contending thread is attempting to access the shared resource;

program instructions, responsive to receiving the request to deschedule the thread, to schedule the thread to complete execution of the instructions to access to the shared resource; and

program instructions, responsive to scheduling the thread to complete execution, to determine processor usage debt accumulated by the thread, wherein the processor usage debt comprises an amount of time for which the thread is executing while the thread has both insufficient processor usage allowance to continue execution and is accessing the shared resource.

17. The computer system of claim 16, further comprising program instructions, stored on the one or more computer readable storage media, for execution by the at least one of the one or more computer processors, to:

responsive to determining that the thread has completed execution of the instructions to perform the action, suspend the thread for an amount of time equal to the determined processor usage debt accumulated by the thread.

18. The computer system of claim 15, wherein the program instructions to manage the schedule of the thread comprise:

program instructions to schedule the thread for execution of the instructions to perform the action;

program instructions to receive a request to deschedule the thread, wherein the request is made in response to determining that the thread has insufficient processor usage allowance to continue execution;

program instructions, responsive to receiving a request to deschedule the thread, to schedule the thread to complete execution of the instructions to execute the critical section of code; and

program instructions, responsive to scheduling the thread to complete execution, to determine processor usage debt accumulated by the thread, wherein the processor usage debt comprises an amount of time for which the thread is executing while the thread has both insufficient processor usage allowance to continue execution and is executing the critical section of code.

19. The computer system of claim 18, further comprising program instructions, stored on the one or more computer readable storage media, for execution by the at least one of the one or more computer processors, to:

responsive to determining that the thread has completed execution of the instructions to perform the action, suspend the thread for an amount of time equal to the determined processor usage debt accumulated by the thread.

20. The computer system of claim 15, wherein the program instructions to manage the schedule of the thread comprise:

program instructions, before scheduling the thread for execution of the instructions to perform the action, to determine if the thread has a first processor usage allowance that is sufficient to complete execution of the instructions to perform the action;

program instructions, responsive to determining that the thread has the first processor usage allowance that is sufficient, to schedule the thread to complete execution of the instructions to perform the action; and

program instructions, responsive to determining that the thread has the first processor usage allowance that is not sufficient, to suspend the thread until the thread has sufficient processor usage allowance.