Method and apparatus for computer system power management

• US 5,692,204 A
• Filed: 06/19/1996
• Issued: 11/25/1997
• Est. Priority Date: 02/15/1995
• Status: Expired due to Term

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Rawson, Andrew Radcliffe, Sotomayor, Guy Gil Jr.
• Primary Examiner(s): Sheikh, Ayaz R.
• Application Number:
  US08/666,149
• Time in Patent Office: 524 Days
• Field of Search: 395/750, 364/707
• US Class Current: 713/340
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A method and apparatus for managing power states of at least one hardware resource, including registering at least one hardware resource power state corresponding to a software process, determining whether a current hardware resource power state fulfills the registered hardware resource power state corresponding to the software process, and modifying the current hardware resource power state that is determined not to fulfill the registered hardware resource power state prior to executing the software process.

Claims

1. An apparatus for managing power states of hardware resources of a computing system comprising:

means for receiving a service call from a software process;

means, responsive to said service call, for registering a power state of at least one hardware resource to be utilized by an application program; and

means for comparing a current power state of said at least one hardware resource to said registered power state and means for modifying said current power state prior to executing said application program if said current power state is lower than said registered power state.

2. The apparatus of claim 1 wherein said computing system is a multi-tasking computing system, said means for receiving includes means for receiving service calls from a first set of software processes, said means for registering includes means for registering power states of hardware resources to be utilized by said first set of software processes, and said means for modifying includes means for modifying power states of hardware resources to be utilized by said first set of software processes if current power states are lower than said registered power states.

3. The apparatus of claim 2 wherein a second set of software processes are executed before said step of modifying if current power states of hardware resources to be used by both the first and the second set of software processes are equal or higher than power states registered in response to service calls received from said second set of software processes.

4. The apparatus of claim 2 wherein additional hardware resource power states are registered during execution of said first set of software processes.

5. The apparatus of claim 2 wherein an operating system maintains a history of a second set of said plurality of software processes for determining what hardware resource power states correspond to said second set of software processes.

6. The apparatus of claim 5 wherein said application program is a software process.

34. The apparatus of claim 4 wherein said first set of software processes being executed initiates service calls for either itself and/or a second set of software processes.

7. A method for managing power states of hardware resources of a computing system comprising the steps of:

receiving a service call from a software process;

registering, in response to said service call, a power state of at least one hardware resource to be utilized by an application program; and

comparing a current power state of said at least one hardware resource to said registered power state and modifying said current power state prior to executing said application program if said current power state is lower than said registered power state.

8. The method of claim 7 wherein said computing system is a multi-tasking system, said step of receiving includes the step of receiving service calls from a first set of software processes, said step of registering includes the step of registering power states of hardware resources to be utilized by said first set of software processes, and said step of modifying includes the step of modifying power states of hardware resources to be utilized by said first set of software processes if current power states are lower than said registered power states.

9. The method of claim 8 wherein a second set of said software processes are executed before said step of modifying if current power states of hardware resources to be used by both the first and the second set of software processes are equal or higher than power states registered in response to service calls received from said second set of software processes.

10. The method of claim 8 wherein additional hardware resource power states are registered during execution of said first set of software processes.

11. The method of claim 8 wherein an operating system maintains a history of a second set of said plurality of software processes for determining what hardware resource power states correspond to said second set of software processes.

12. The method of claim 11 wherein said application program is a software process.

13. The method of claim 10 wherein said first set of software processes being executed initiates service calls for either itself and/or a second set of software processes.

14. A data processing system for managing power states of hardware resources of a computing system comprising:

a memory for storing data to be processed;

a processor for processing data;

means for receiving a service call from a software process;

means, responsive to said service call, for registering a power state of at least one hardware resource to be utilized by an application program; and

means for comparing a current power state of said at least one hardware resource to said registered power state and means for modifying said current power state prior to executing said application program if said current power state is lower than said registered power state.

15. The data processing system of claim 14 wherein said computing system is a multi-tasking computing system, said means for receiving includes means for receiving service calls from a first set of software processes, said means for registering includes means for registering power states of hardware resources to be utilized by said first set of software processes, and said means for modifying includes means for modifying power states of hardware resources to be utilized by said first set of software processes if current power states are lower than said registered power states.

16. The data processing system of claim 15 wherein a second set of software processes are executed before said step of modifying if current power states of hardware resources to be used by both the first and the second set of software processes are equal or higher than power states registered in response to service calls received from said second set of software processes.

17. The data processing system of claim 15 wherein additional hardware resource power states are registered during execution of said first set of software processes.

18. The data processing system of claim 15 wherein an operating system maintains a history of a fourth set of said plurality of software processes for determining what hardware resource power states correspond to said fourth set of software processes.

19. The data processing system of claim 18 wherein said application program is a software process.

20. The data processing system of claim 17 wherein said first set of software processes being executed initiates service calls for either itself and/or a second set of software processes.

21. A computer program product stored in memory and executable by a processor for managing power states of hardware resources of a computing system comprising:

means, stored in memory, for receiving a service call from a software process;

means, stored in memory and responsive to said service call, for registering a power state of at least one hardware resource to be utilized by an application program; and

means, stored in memory, for comparing a current power state of said at least one hardware resource to said registered power state and for modifying said current power state prior to executing said application program if said current power state is lower than said registered power state.

22. The computer program product of claim 21 wherein said computing system is a multi-tasking computing system, said means stored in memory for receiving includes means for receiving service calls from a first set of software processes, said means stored in memory for registering includes means for registering power states of hardware resources to be utilized by said first set of software processes, and said means stored in memory for modifying includes means for modifying power states of hardware resources to be utilized by said first set of software processes if current power states are lower than said registered power states.

23. The computer program product of claim 22 wherein a second set of software processes are executed before said step of modifying if current power states of hardware resources to be used by both the first and the second set of software processes are equal or higher than power states registered in response to service calls received from said second set of software processes.

24. The computer program product of claim 22 wherein additional hardware resource power states are registered during execution of said first set of software processes.

25. The computer program product of claim 22 wherein an operating system maintains a history of a second set of said plurality of software processes for determining what hardware resource power states correspond to said second set of software processes.

26. The computer program product of claim 25 wherein said application program is a software process.

27. The computer program product of claim 24 wherein said first set of software processes being executed initiates service calls for either itself and/or a second set of software processes.

28. An apparatus for obtaining power states of at least one hardware resource, comprising:

means for requesting at least one hardware resource power state corresponding to a software process, said requesting means including means for receiving a service call from a command script, said command script being written by a user if said software process is power management unaware;

means for waiting for a response that confirms a current hardware resource power state fulfills said requested hardware resource power state; and

means for executing the software process upon receiving the response.

29. The apparatus of claim 28 further comprising means for suspending execution of the software process and for requesting at least one hardware resource power state corresponding to the software process while the execution of the software process is suspended.

30. A method of obtaining power states of at least one hardware resource, comprising the steps of:

requesting at least one hardware resource power state corresponding to a software process, said step of requesting including the step of receiving a service call from a command script written by a user if said software process is power management unaware;

waiting for a response that confirms a current hardware resource power state fulfills said requested hardware resource power state; and

executing the software process upon receiving the response.

31. The method of claim 30 further comprising a step of suspending execution of the software process and requesting at least one hardware resource power state corresponding to the software process while the execution of the software process is suspended.

32. A computer program product stored in memory and executable by a processor for obtaining power states of at least one hardware resource, comprising:

means, stored in memory, for requesting at least one hardware resource power state corresponding to a software process, said requesting means including means stored in memory for receiving a service call from a command script written by a user if said software process is power management unaware;

means, stored in memory, for waiting for a response that confirms a current hardware resource power state fulfills said requested hardware resource power state; and

means, stored in memory, for executing the software process upon receiving the response.

33. The computer program product of claim 32 further comprising means, stored in memory, for suspending execution of the software process and for requesting at least one hardware resource power state corresponding to the software process while the execution of the software process is suspended.

35. An apparatus for scheduling executions of software processes in a multi-tasking computing system comprising:

means for receiving required minimum power states of hardware resources to be utilized by said software processes;

means for determining current power states of said hardware resources; and

means, responsive to said receiving and determining means, for scheduling execution of said software processes.

36. The apparatus of claim 35 wherein software processes using hardware resources with required minimum power states meeting current power states of said hardware resources are scheduled to be executed first.

37. The apparatus of claim 36 wherein software processes using hardware resources with required minimum power states being next levels of current power states of said hardware resources are scheduled to be executed next.

38. The apparatus of claim 37 wherein upgrading current power states of said hardware resources to said next levels of power states occurs during execution of software processes.

39. A method of scheduling executions of software processes in a multi-tasking computing system comprising the steps of:

receiving required minimum power states of hardware resources to be utilized by said software processes;

determining current power states of said hardware resources; and

using said minimum power states and said current power states to schedule execution of said software processes.

40. The method of claim 39 wherein software processes using hardware resources with required minimum power states meeting current power states of said hardware resources are scheduled to be executed first.

41. The method of claim 40 wherein software processes using hardware resources with required minimum power states being next levels of current power states of said hardware resources are scheduled to be executed next.

42. The method of claim 41 wherein upgrading current power states of said hardware resources to said next levels of power states occurs during execution of software processes.

43. A computer program product stored in memory and executable by a processor for scheduling executions of software processes in a multi-tasking computing system comprising:

computer executable means for receiving required minimum power states of hardware resources to be utilized by said software processes;

computer executable means for determining current power states of said hardware resources; and

computer executable means, responsive to said receiving and determining means, for scheduling execution of said software processes.

44. The computer program product of claim 43 wherein software processes using hardware resources with required minimum power states meeting current power states of said hardware resources are scheduled to be executed first.

45. The computer program product of claim 44 wherein software processes using hardware resources with required minimum power states being next levels of current power states of said hardware resources are scheduled to be executed next.

46. The computer program product of claim 45 wherein upgrading current power states of said hardware resources to said next levels of power states occurs during execution of software processes.