Non-preemption of a group of interchangeable tasks in a computing device

• US 9,632,844 B2
• Filed: 12/12/2013
• Issued: 04/25/2017
• Est. Priority Date: 12/12/2013
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Pai, Ramachandra N, Wang, Yun, Xiao, Guang Rong, Yang, Wei
• Primary Examiner(s): PATEL, HIREN P
• Application Number:
  US14/105,060
• Publication Number:
  US 20150169364A1
• Time in Patent Office: 1,230 Days
• Field of Search: None
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
• CPC Class Codes: G06F 9/54 Interprogram communication

Abstract

A non-preemption task group apparatus comprises a scheduling module that identifies a first task that is one of executing and scheduled to execute on a processor during a first time slice and a second task to be executed on a processor during a subsequent time slice, the first slice occurring before the subsequent slice, a relationship module that compares the first task to the second task, and an examining module that identifies whether the first task and the second task are interchangeable tasks based on the comparison, wherein the first task executes during the subsequent time slice in response to the first task and the second task being identified as interchangeable.

Claims

1. An apparatus comprising:

a scheduling module that identifies a first task that is one of executing and scheduled to execute on a processor during a first time slice and a second task scheduled to be executed on the processor during a subsequent time slice immediately adjacent to the first time slice, the first time slice occurring before the subsequent time slice;

a relationship module that compares the first task to the second task;

an examining module that identifies whether the first task and the second task are interchangeable tasks based on the comparison, wherein interchangeable tasks share context information and belong to a common job;

a task queuing module that assigns the first task and the second task to adjacent time slices in response to the first task and the second task being identified as interchangeable tasks; and

an interrupt handling module that suppresses delivery of an interrupt signal at the end of the first time slice in response to the first task and the second task being identified as interchangeable tasks,

wherein the first task executes during the subsequent time slice in response to the first task and the second task being identified as interchangeable tasks,

wherein at least a portion of the scheduling module, the relationship module, the examining module, the task queuing module, and the interrupt handling module comprise one or more of a hardware circuit and program instructions stored on one or more non-transitory computer readable media.

2. The apparatus of claim 1, wherein the second task executes during the subsequent time slice in response to identifying that the first task and the second task are not interchangeable tasks.

3. The apparatus of claim 1, wherein the relationship module compares a first task group identifier of the first task to a second task group identifier of the second task, and wherein the examining module determines whether the first task group identifier matches the second task group identifier.

4. The apparatus of claim 1, wherein the examining module identifies whether the first task and the second task belong to a common group of interchangeable tasks.

5. The apparatus of claim 1, further comprising:

a task grouping module that identifies at least two interchangeable tasks scheduled to execute on the processor and associates an indicator with the at least two interchangeable tasks, the indicator designating that the at least two tasks are part of a common group of interchangeable tasks,

wherein the examining module evaluates the indicator to determine whether the first task and the second task are part of the group of interchangeable tasks.

6. The apparatus of claim 1, further comprising a load assessing module that identifies a processor load, wherein the relationship module compares the first task to the second task in response to the processor load being identified as one of moderate and heavy.

7. The apparatus of claim 1, wherein during a time when the first task is executing on the processor, further comprising:

receiving an interrupt signal at an end of the first time slice; and

identifying whether the first task and the second task are interchangeable in response to receiving the interrupt signal.

8. The apparatus of claim 1, further comprising:

identifying a plurality of interchangeable tasks scheduled for execution on the processor; and

assigning consecutive time slices to the plurality of interchangeable tasks.

9. The apparatus of claim 1, wherein the processor is a central processing unit having a plurality of processing cores, and wherein the first task and the second task are assigned to a common processing core of the plurality of processing cores.

10. The apparatus of claim 1, further comprising allocating time slices equally to tasks scheduled to execute on the processor, the tasks scheduled including the first task and the second task.

11. The apparatus of claim 1, further configured to:

identify a second time slice allocated to the first task; and

execute the second task during the second time slice.

12. A computer program product comprising:

at least one non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code, when read by a processor, configured to;

identify a first task that is one of executing and scheduled to execute on a processor during a first time slice;

identify a second task scheduled to be executed on the processor during a subsequent time slice immediately adjacent to the first time slice, the first time slice occurring before the subsequent time slice;

compare the first task to the second task;

identify whether the first task and the second task are interchangeable tasks based on the comparison, wherein interchangeable tasks share context information and belong to a common job;

assign the first task and the second task to adjacent time slices in response to the first task and the second task being identified as interchangeable tasks; and

an interrupt handling module that suppresses delivery of an interrupt signal at the end of the first time slice in response to the first task and the second task being identified as interchangeable tasks,

execute the first task during the subsequent time slice in response to the first task and the second task being identified as interchangeable tasks.

13. The computer program product of claim 12, further comprising executing the second task during the subsequent time slice in response to identifying that the first task and the second task are not interchangeable tasks.

14. The computer program product of claim 12, wherein comparing the first task to the second task comprises comparing a first task group identifier of the first task to a second task group identifier of the second task, and wherein identifying whether the first task and the second task are interchangeable comprises determining whether the first task group identifier matches the second task group identifier.

15. The computer program product of claim 12, further comprising:

identifying at least two interchangeable tasks scheduled to execute on the processor; and

associating an indicator with the at least two interchangeable tasks, the indicator designating that the at least two tasks are part of a common group of interchangeable tasks,

wherein identifying whether the first task and the second task are interchangeable tasks comprises evaluating the indicator to determine whether the first task and the second task are part of the group of interchangeable tasks.

16. The computer program product of claim 12, wherein during a time when the first task is executing on the processor, further comprising:

receiving an interrupt signal at an end of the first time slice; and

identifying whether the first task and the second task are interchangeable in response to receiving the interrupt signal.

17. The computer program product of claim 12, further comprising:

identifying a plurality of interchangeable tasks scheduled for execution on the processor; and

assigning consecutive time slices to the plurality of interchangeable tasks.

18. The computer program product of claim 12, the computer readable program code, when read by a processor, further configured to:

identify a second time slice allocated to the first task; and

execute the second task during the second time slice.