Methods and apparatuses for dynamic power control

• US 7,802,120 B2
• Filed: 01/05/2006
• Issued: 09/21/2010
• Est. Priority Date: 08/25/2005
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Cox, Keith A., Conroy, David G., Culbert, Michael
• Primary Examiner(s): CHEN, TSE W
• Application Number:
  US11/327,275
• Publication Number:
  US 20070049133A1
• Time in Patent Office: 1,720 Days
• Field of Search: 713/300, 713/340
• US Class Current: 713/340
• CPC Class Codes: G05D 23/19 characterised by the use of electric means G05D23/1393 takes precedence
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/28 Supervision thereof, e.g. detecting power-supply failure by out of limits supervision
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06F 1/3296 by lowering the supply or operating voltage
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

Exemplary embodiments of methods and apparatuses to dynamically redistribute power in a system that includes a plurality of subsystems are described. A load profile of the system is identified. The power is redistributed between the subsystems while tracking the load profile. The load profile may be an asymmetric, or a balanced load profile. The load profile is identified based on a utilization factor for each of the subsystems. In one embodiment, the power used by each of the subsystems is sensed by one or more sensors or predicted or estimated. A utilization factor, which may be a ratio of the actual power used by the subsystem to the power allocated to the subsystem, is calculated. The load profile is determined using the utilization factor of each of the subsystems. A power weighting arrangement between the subsystems, for example, a power distribution table, is selected based on the load profile.

Claims

1. A method, comprising:

calculating a load profile of a system that has a plurality of subsystems, wherein the load profile relates workloads of at least two of the subsystems to each other, selecting a power weighting arrangement between the subsystems that is associated with the load profile, and redistributing a power of the system between the subsystems based on the selected power weighting arrangement, wherein the calculating the load profile includes determining a utilization factor for each of the subsystems; and

subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

2. The method of claim 1, wherein the load profile is an asymmetric load profile and wherein the power is redistributed by setting new allocated amounts of available power usage among the subsystems.

3. The method of claim 1, wherein the calculating the load profile includes sensing the power used by each of the subsystems;

and determining the load profile using the utilization factors of a set of each of the subsystems.

4. The method of claim 1, wherein the utilization factor is a ratio of the power used by the subsystem to the power allocated to the subsystem.

5. The method of claim 1, further including

adding an another subsystem to the plurality of the subsystems;

identifying an another load profile of the system that includes the another subsystem; and

redistributing the power of the system between the subsystems based on the another load profile.

6. The method of claim 5, wherein the identifying the another load profile includes determining the utilization factor for the added subsystem.

7. A method to redistribute a power in a system having a plurality of subsystems, comprising:

(a) determining a power used by each of the subsystems;

(b) determining for each of the subsystems a utilization factor;

(c) calculating a load profile of the system, wherein the load profile relates utilization factors of at least two of the subsystems to each other; and

(d) selecting a power distribution table including powers allocated to the subsystems that corresponds to the load profile, wherein the calculating the load profile includes subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

8. The method of claim 7, wherein the utilization factor is a ratio of the power used by a subsystem to the power allocated to the subsystem and wherein the determining comprises at least one of sensing the power or estimating the power and wherein the power distribution table is used to set new allocated amounts of available power usage among the subsystems.

9. The method of claim 7, further including

repeating (a) to (c) in a sequence;

determining whether a current load profile is different from the load profile determined previously; and

if the load profile is different,

selecting the power distribution table that corresponds to the current load profile.

10. The method of claim 7, further comprising

generating a plurality of power distribution tables corresponding to different load profiles.

11. The method of claim 7, wherein the plurality of the subsystems include

a central processing unit, and

a graphics processor unit.

12. A system, comprising:

a plurality of subsystems, one or more sensors coupled to the plurality of the subsystems to sense a power used by at least a set of the subsystems; and

a microprocessor coupled to the plurality of the subsystems and to the one or more sensors, wherein the microprocessor is configured to calculate a load profile of the system, wherein the load profile relates workloads of at least two of the subsystems to each other in the system;

to select a power weighting arrangement between the subsystems that is associated with the load profile and to dynamically redistribute a power of the system between the subsystems based on the selected power weighting arrangement, wherein the load profile is calculated by using a utilization factor for each of the subsystems; and

subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

13. The system of claim 12, wherein the utilization factor is a ratio of the power used by a subsystem to the power allocated to the subsystem and wherein the power is dynamically redistributed by setting new allocated amounts of available power usage among the subsystems.

14. The system of claim 12, wherein the subsystems include a central processing unit, and a graphics processor unit.

15. The system of claim 12, wherein the microprocessor is configured to calculate a load profile of the system using the utilization factor for each of the subsystems;

and

to select a power distribution table based on the load profile.

16. The system of claim 15, wherein the microprocessor is configured to generate a plurality of power distribution tables corresponding to different load profiles.

17. The system of claim 12, further comprising

a memory coupled to the plurality of the subsystems, wherein the memory stores a plurality of power distribution tables corresponding to different load profiles.

18. The system of claim 12, wherein the system is portable.

19. The system of claim 12, wherein the microprocessor is configured to

add an another subsystem to the plurality of the subsystems, and to

identify another load profile of another system that includes the another subsystem;

and to redistribute the power of the another system between the subsystems based on the another load profile.

20. An article of manufacture comprising:

a machine-readable storage medium storing data that, when accessed by a machine, cause the machine to perform operations comprising, calculating a load profile of a system that has a plurality of subsystems, wherein the load profile relates workloads of at least two of the subsystems to each other;

selecting a power weighting arrangement between the subsystems that is associated with the load profile; and

redistributing a power of the system between the subsystems based on the selected power weighting arrangement, wherein the calculating the load profile includes determining a utilization factor for each of the subsystems, and subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

21. The article of manufacture of claim 20, wherein the load profile is an asymmetric load profile and wherein the power is redistributed by setting new allocated amounts of available power usage among the subsystems.

22. The article of manufacture of claim 20, wherein the calculating the load profile includes sensing the power used by each of the subsystems;

and determining the load profile using the utilization factors of a set of each of the subsystems.

23. The article of manufacture of claim 20, wherein the utilization factor is a ratio of the power used by the subsystem to the power allocated to the subsystem.

24. The article of manufacture of claim 20, wherein the machine-accessible medium further includes data that cause the machine to perform operations, comprising,

adding an another subsystem to the plurality of the subsystems;

identifying an another load profile of the system that includes the another subsystem; and

redistributing the power of the system between the subsystems based on the another load profile.

25. The article of manufacture of claim 24, wherein the identifying the another load profile includes determining the utilization factor for the added subsystem.

26. An article of manufacture comprising:

a machine-readable storage medium storing data that, when accessed by a machine, cause the machine to redistribute a power in a system having a plurality of subsystems that comprises, (a) determining a power used by each of the subsystems;

(b) determining for each of the subsystems an utilization factor;

(c) calculating a load profile of the system, wherein the load profile relates utilization factors of at least two of the subsystems to each other in the system; and

(d) selecting a power distribution table including powers allocated to the subsystems that corresponds to the load profile, wherein the calculating the load profile includes subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

27. The article of manufacture of claim 26, wherein the utilization factor is a ratio of the power used by a subsystem to the power allocated to the subsystem and wherein the determining comprises at least one of sensing the power or estimating the power.

28. The article of manufacture of claim 26, wherein the machine-accessible medium further includes data that cause the machine to perform operations comprising,

repeating (a) to (c) in a sequence;

determining whether a current load profile is different from the load profile determined previously; and

if the load profile is different,

selecting the power distribution table that corresponds to the current load profile.

29. The article of manufacture of claim 26, wherein the machine-accessible medium further includes data that cause the machine to perform operations comprising,

generating a plurality of power distribution tables corresponding to different load profiles.

30. The article of manufacture of claim 26, wherein the plurality of the subsystems include

a central processing unit, and

a graphics processor unit.

31. A system, comprising means for calculating a load profile of a system that has a plurality of subsystems, wherein the load profile relates workloads of at least two of the subsystems to each other;

means for selecting a power weighting arrangement between the subsystems that is associated with the load profile; and

means for redistributing a power of the system between the subsystems based on the selected power weighting arrangement, wherein the means for calculating the load profile include means for determining a utilization factor for each of the subsystems, and subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

32. The system of claim 31, wherein the load profile is an asymmetric load profile.

33. The system of claim 31, wherein the means for redistributing the power include

means for selecting a power weighting arrangement between the subsystems in the system.

34. The system of claim 31, wherein the means for calculating the load profile include means for sensing the power used by each of the subsystems;

and means for determining the load profile using the utilization factor of each of the subsystems.

35. The system of claim 31, wherein the utilization factor is a ratio of the power used by the subsystem to the power allocated to the subsystem.

36. The system of claim 31, further including

means for adding an another subsystem to the plurality of the subsystems;

means for identifying an another load profile of the system that includes an added subsystem; and

means for redistributing the power of the system between the subsystems based on the another load profile.

37. The system of claim 36, wherein the means for identifying the another load profile includes means for determining the utilization factor for the added subsystem.

38. A system to redistribute a power between a plurality of subsystems, comprising:

means for (a) determining a power used by each of the subsystems;

means for (b) determining for each of the subsystems an utilization factor;

means for (c) calculating a load profile of the system wherein the load profile relates utilization factors of at least two of the subsystems to each other; and

means for (d) selecting a power distribution table including powers allocated to the subsystems that corresponds to the load profile wherein the means for calculating the load profile include means for subtracting the utilization factor of a first subsystem from the utilization factor of a second subsystem.

39. The system of claim 38, wherein the utilization factor is a ratio of the power used by a subsystem to the power allocated to the subsystem.

40. The system of claim 38, further including

means for repeating (a) to (c) in a sequence;

means for determining whether a current load profile is different from the load profile determined previously; and

means for selecting the power distribution table that corresponds to the current load profile, if the load profile is different.

41. The system of claim 38, further comprising

means for generating a plurality of power distribution tables corresponding to different load profiles.

42. The system of claim 38, wherein the plurality of the subsystems include

a central processing unit, and

a graphics processor unit.