System and method for managing power usage of a data processing system subsystem

• US 20060282686A1
• Filed: 06/09/2005
• Published: 12/14/2006
• Est. Priority Date: 06/09/2005
• Status: Active Grant

• Current Assignee: Lenovo International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Bahali, Sumanta K., Bailey, Warren D., Foster, Jimmy G. Sr., Sellman, Gregory D.
• Granted Patent: US 7,664,968 B2
• Time in Patent Office: Days
• US Class Current: 713/300
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode

Abstract

A system and method for managing power usage of a data processing system subsystem are disclosed. According to one embodiment, a power-managed server data processing system is provided which comprises a bus configured to communicatively couple the power-managed server with a data processing system resource; and a bus controller coupled to the bus. In the described embodiment, the bus controller comprises bus control logic configured to process a plurality of access requests associated with the bus, and power management logic configured to inhibit processing of a current access request of the plurality by the bus control logic for a power management delay time period. The power management delay time period is determined utilizing a processing latency time period associated with a prior access request of the plurality of access requests.

Claims

1. A power-managed server data processing system comprising:

a bus configured to communicatively couple said power-managed server data processing system with a data processing system resource; and

a bus controller coupled to said bus, said bus controller comprising

bus control logic configured to process a plurality of access requests associated with said bus, and

power management logic configured to inhibit processing of a current access request of said plurality of access requests by said bus control logic for a power management delay time period, wherein

said power management delay time period is determined utilizing a processing latency time period associated with a prior access request of said plurality of access requests.

2. The power-managed server data processing system of claim 1, wherein

said bus controller further comprises a storage element,

said power-managed server data processing system further comprises

a system management processor coupled to said bus controller and configured to cause data specifying a power management level to be stored utilizing said storage element, and

said power management logic is configured to inhibit said processing of said current access request in response to a storage of said data specifying said power management level utilizing said storage element.

3. The power-managed server data processing system of claim 2, wherein

said power-managed server data processing system comprises one of a plurality of server data processing systems, and

said system management processor is configured to determine said data specifying said power management level in response to a receipt of a first power management command local to said power-managed server data processing system and a second power management command from a power management server data processing system of said plurality of server data processing systems.

4. The power-managed server data processing system of claim 1, wherein said plurality of access requests comprise a plurality of requests to access said data processing system resource utilizing said bus.

5. The power-managed server data processing system of claim 1, wherein said latency time period associated with said prior access request comprises a time period utilized by said bus control logic to process said prior access request.

6. The power-managed server data processing system of claim 1, wherein

said data processing system resource comprises a data processing system memory element,

said bus controller comprises a memory controller, and

said prior access request comprises an access request immediately preceding said current access request in time.

7. The power-managed server data processing system of claim 1, wherein

said data processing system resource comprises a data processing system input/output element,

said bus controller comprises an input/output bridge arbitration control point, and

said power management delay time period is determined utilizing an average processing latency time period associated with a predetermined number of access requests of said plurality of access requests preceding said current access request in time.

8. A method for managing power usage within a data processing resource coupled with a power-managed server data processing system via a bus, said method comprising:

processing a plurality of access requests associated with said bus;

determining a processing latency time period associated with a prior access request of said plurality of access requests; and

inhibiting processing of a current access request for a power management delay time period, wherein

said power management delay time period is determined utilizing said processing latency time period.

9. The method of claim 8, further comprising

causing data specifying a power management level to be stored utilizing a storage element associated with said power-managed server data processing system;

and

inhibiting said processing of said current access request in response to said causing.

10. The method of claim 9, wherein

said power-managed server data processing system comprises one of a plurality of server data processing systems, and

said method further comprises

determining said data specifying said power management level in response to a receipt of a first power management command local to said power-managed server data processing system and a second power management command from a power management server data processing system of said plurality of server data processing systems.

11. The method of claim 8, wherein said plurality of access requests comprise a plurality of requests to access said data processing system resource utilizing said bus.

12. The method of claim 8, wherein said latency time period associated with said prior access request comprises a time period utilized to process said prior access request.

13. The method of claim 8, wherein

said data processing system resource comprises a data processing system memory element, and

said prior access request comprises an access request immediately preceding said current access request in time.

14. The method of claim 8, wherein

said data processing system resource comprises a data processing system input/output element, and

said power management delay time period is determined utilizing an average processing latency time period associated with a predetermined number of access requests of said plurality of access requests preceding said current access request in time.

17. The machine-readable medium of claim 9, wherein

said power-managed server data processing system comprises one of a plurality of server data processing systems, and

said method further comprises

determining said data specifying said power management level in response to a receipt of a first power management command local to said power-managed server data processing system and a second power management command from a power management server data processing system of said plurality of server data processing systems.

15. A machine-readable medium having a plurality of instructions executable by a machine embodied therein, wherein said plurality of instructions when executed cause said machine to perform a method for managing power usage within a data processing resource coupled with a power-managed server data processing system via a bus, said method comprising:

processing a plurality of access requests associated with said bus;

determining a processing latency time period associated with a prior access request of said plurality of access requests; and

inhibiting processing of a current access request for a power management delay time period, wherein

said power management delay time period is determined utilizing said processing latency time period.

16. The machine-readable medium of claim 15, said method further comprising

causing data specifying a power management level to be stored utilizing a storage element associated with said power-managed server data processing system;

and

inhibiting said processing of said current access request in response to said causing.

18. The machine-readable medium of claim 15, wherein said latency time period associated with said prior access request comprises a time period utilized to process said prior access request.

19. The machine-readable medium of claim 15, wherein

said data processing system resource comprises a data processing system memory element, and

said prior access request comprises an access request immediately preceding said current access request in time.

20. The machine-readable medium of claim 15, wherein

said data processing system resource comprises a data processing system input/output element, and

said power management delay time period is determined utilizing an average processing latency time period associated with a predetermined number of access requests of said plurality of access requests preceding said current access request in time.