Resource reservation and priority management

• US 20030061260A1
• Filed: 09/25/2001
• Published: 03/27/2003
• Est. Priority Date: 09/25/2001
• Status: Abandoned Application

• Current Assignee: Timesys Corporation
• Original Assignee: Timesys Corporation
• Inventors: Rajkumar, Ragunathan
• Application Number:
  US09/962,925
• Publication Number:
  US 20030061260A1
• Time in Patent Office: Days
• US Class Current: 718/104
• CPC Class Codes: G06F 9/4887 involving deadlines, e.g. rate based, periodic
• CPC Class Codes: G06F 9/50 Allocation of resources, e.g. of the central processing unit [CPU]

Abstract

A method for resource management in a real-time data processing system. Multiple tasks having potentially different resource data processing resource requirements are scheduled to run concurrently. A first subset of tasks are defined as reservation activities, each having specified parameters for determining priority among other reservation activities. Specified reservation activity parameters may include a resource consumption amount, execution time period, deadline, start time and/or reservation lifetime. The system also supports resource allocation among fixed-priority activities, such as may be legacy interrupt-driven or operating system tasks. The fixed-priority activities may themselves have fixed priorities with respect to other fixed priority activities. The fixed priority activities may themselves execute importantly at collective priority which is less than those allocated for at least one of the reservation activities. The co-existence of fixed-priority activities with reserves is also applicable to dynamic-priority activities. Finally, reservations can be created inside parent reservations.

Claims

1. A method for resource management in a data processing system in which multiple tasks with different requirements are scheduled to run concurrently, the tasks being assigned to different data processing activities, the method comprising the steps of:

allocating resource accesses on a reservation activity basis, each such reservation having specified parameters for determining a priority allocation among other reservation activities;

allocating other resource accesses as fixed priority activities, the fixed priority activities each having a priority value with respect to other fixed priority activities; and

wherein the fixed priority activities are given a lower priority than at least one of the reservation activities.

2. A method as in claim 1 in which the data processing system is a real-time system.

3. A method as in claim 1 wherein the different requirements are time constraints.

4. A method as in claim 1 wherein the different requirements are data processing resource requirements.

5. A method as in claim 1 wherein the specified parameters for determining priority are reservation time-based parameters.

6. A method as in claim 5 wherein the specified parameters for the reservation based priority allocation are selected from a group consisting of resource consumption time C, time period T, and deadline D.

7. A method as in claim 1 additionally comprising the step of:

operating a resource kernel to provide guaranteed and timely access to requirements for the reservation activities.

8. A method as in claim 1 wherein the reservation activities are selected from a group consisting of resource sets, tasks, and reservations.

9. A method as in claim 4 wherein the resource is selected from a group consisting of central processing unit cycles, network bandwidth, disk access bandwidth, input device bandwidth, and output device bandwidth.

10. A method as in claim 1 wherein a default reservation activity is allocated to the fixed-priority and background-priority activities collectively.

11. A method for resource management in a data processing system in which multiple tasks with different requirements are scheduled to run concurrently, the tasks being assigned to different data processing system activities, comprising the steps of:

making allocations for the execution of reservation activities, each reservation activity having specified parameters for determining priority allocation among other reservation activities;

making allocations for the execution of a plurality of concurrent tasks running within a single reservation activity; and

such that the aggregation of concurrent tasks are collectively constrained by the parameters of the reservation activity.

12. A method as in claim 11 wherein the data processing system is a real-time operating system.

13. A method as in claim 11 wherein the different requirements are time constraints.

14. A method as in claim 11 wherein the different requirements are resource requirements.

15. A method as in claim 11 additionally comprising the step of:

operating a resource kernel to provide guaranteed access to resources for the reservation activities.

16. A method as in claim 11 wherein the reservation activities are selected from a group consisting of resource sets, tasks, and reservations.

17. A method as in claim 11 wherein the specified parameters for a reservation activity are resource consumption C, time period T, and deadline D.

18. A method as in claim 14 wherein the resource is selected from a group consisting of central processing unit time, network bandwidth, disk access bandwidth, input device bandwidth, and output device bandwidth.

19. A method for resource management in a data processing system in which multiple tasks are scheduled to run concurrently, the tasks being assigned to different data processing system activities, comprising the steps of:

executing a first-level reservation activity, the reservation activity having specified parameters for determining priority allocation among other reservation activities; and

executing one or more secondary-level reservation activities, each having specified parameters for determining a reservation time-based priority, the specified parameters for the secondary-level activities collectively constrained by their associated specified parameters for their associated first-level reservation activity.

20. A method as in claim 19 wherein the secondary-level reservation activities are themselves composed of further hierarchical level activities encompassing at least a third tertiary-level reservation activity.

21. A method for resource management in a data processing system in which multiple tasks are scheduled to run concurrently, the tasks being assigned to different data processing system activities comprising the steps of:

allocating reservation activities, each having specified parameters for determining a reservation time-based priority allocation among other reservation activities;

scheduling the reservation activity as a background activity after the reservation time has been consumed should the specified resource become available; and

such that the background activity may be further assigned a preferential priority.

22. A method as in claim 21 additionally comprising wherein the background activity may be further assigned a preferential priority such that background activities having a preferential priority are scheduled before those having a non-preferential background activity priority assignments.

23. A method for resource management in a data processing system in which multiple tasks with different time constraints and/or resource requirements are scheduled to run concurrently, the tasks being assigned to different data processing system activities, comprising the steps of:

providing for the execution of reservation activities, each having specified parameters for determining a reservation time-based priority allocation among other reservation activities; and

providing for the executing of one or more system level activities, having at least one critical activity having a priority higher than the reservation activities.

24. A method for resource management in a data processing system in which multiple tasks with different time constraints and/or resource requirements are scheduled to run concurrently, the tasks being assigned to different data processing system activities, comprising the steps of:

providing for the execution of reservation activities, each having specified parameters for determining a reservation time-based priority allocation among other reservation activities; and

providing for the execution of one or more critical system activities, schedulable themselves as a reservation activity.

25. A method for resource management in a data processing system in which multiple tasks with different requirements are scheduled to run concurrently, the tasks being assigned to different data processing activities, the method comprising the steps of:

allocating resource accesses on a reservation activity basis, each such reservation having specified parameters for determining a priority allocation among other reservation activities;

allocating other resource accesses as dynamic priority activities, the dynamic priority activities each having a priority value with respect to other dynamic priority activities; and

wherein the dynamic priority activities are given a lower priority than at least one of the reservation activities.

26. A method as in claim 25 in which the data processing system is a real-time system.

27. A method as in claim 25 wherein the different requirements are time constraints.

28. A method as in claim 25 wherein the different requirements are data processing resource requirements.

29. A method as in claim 25 wherein the specified parameters for determining priority are reservation time-based parameters.

30. A method as in claim 25 wherein the specified parameters for the reservation based priority allocation are selected from a group consisting of resource consumption time C, time period T, and deadline D.

31. A method as in claim 25 additionally comprising the step of:

operating a resource kernel to provide guaranteed and timely access to requirements for the reservation activities.

32. A method as in claim 25 wherein the reservation activities are selected from a group consisting of resource sets, tasks, and reservations.

33. A method as in claim 25 wherein the resource is selected from a group consisting of central processing unit cycles, network bandwidth, disk access bandwidth, input device bandwidth, and output device bandwidth.

34. A method as in claim 25 wherein a default reservation activity is allocated to the dynamic-priority and background-priority activities collectively.