Operating system-independent method and system of determining CPU utilization

• US 20020087291A1
• Filed: 12/29/2000
• Published: 07/04/2002
• Est. Priority Date: 12/29/2000
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Cooper, Barnes
• Granted Patent: US 6,711,526 B2
• Time in Patent Office: Days
• US Class Current: 702/186
• CPC Class Codes: G06F 11/3423 where the assessed time is active or idle time

Abstract

The utilization of a central processing unit during a sampling time interval is determined by measuring a time quantum within the sampling time interval during which a central processing unit clock signal is active within a processor core of the central processing unit. The total number of cycles of the central processing unit clock signal that are applied to the processor core and the period of the central processing unit clock signal are used to determine the time quantum. The utilization may then be expressed in terms of a ratio of the time quantum to the total time interval.

Claims

1. A method comprising:

measuring a time quantum within a sampling time interval during which a central processing unit clock signal is active within a processor core of a central processing unit; and

determining a utilization of said central processing unit during said sampling time interval utilizing said time quantum.

2. The method as set forth in claim 1, wherein measuring a time quantum within a sampling time interval during which a central processing unit clock signal is active within a processor core of a central processing unit comprises accumulating all time quanta within said sampling time interval during which said central processing unit clock signal is applied to said processor core.

3. The method as set forth in claim 1, wherein determining a utilization of said central processing unit during said sampling time interval utilizing said time quantum comprises calculating a ratio of said time quantum to said sampling time interval.

4. The method as set forth in claim 1, wherein measuring a time quantum within a sampling time interval during which a central processing unit clock signal is active within a processor core of a central processing unit comprises:

determining a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval; and

calculating said time quantum utilizing said total number of cycles and a period of said central processing unit clock signal.

5. The method as set forth in claim 4, further comprising:

periodically executing a utilization application, wherein said sampling time interval comprises a time interval between a first execution of said utilization application and a second execution of said utilization application.

6. The method as set forth in claim 4, further comprising:

periodically executing a system management interrupt handler, wherein said sampling time interval comprises a time interval between a first execution of said system management interrupt handler and a second execution of said system management interrupt handler.

7. The method as set forth in claim 5, wherein determining a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval comprises:

incrementing a time-stamp counter for each cycle of said central processing unit clock signal that is applied to said processor core during said sampling time interval from an initial value to a final value;

subtracting said initial value of said time-stamp counter from said final value of said time-stamp counter to determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval.

8. The method as set forth in claim 7, further comprising:

reading said initial value of said time-stamp counter in response to said first execution of said utilization application; and

reading said final value of said time-stamp counter in response to said second execution of said utilization application.

9. A data processing system-readable medium having a plurality of instructions executable by a data processing system embodied therein, wherein said instructions when executed cause said data processing system to:

measure a time quantum within a sampling time interval during which a central processing unit clock signal is active within a processor core of a central processing unit; and

determine a utilization of said central processing unit during said sampling time interval utilizing said time quantum.

10. The data processing system-readable medium as set forth in claim 9, wherein said instructions causing said data processing system to measure a time quantum within a sampling time interval during which a central processing unit clock signal is active within a processor core of a central processing unit cause said data processing system to accumulate all time quanta within said sampling time interval during which said central processing unit clock signal is applied to said processor core.

11. The data processing system-readable medium as set forth in claim 9, wherein said instructions causing said data processing system to determine a utilization of said central processing unit during said sampling time interval utilizing said time quantum cause said data processing system to calculate a ratio of said time quantum to said sampling time interval.

12. The data processing system-readable medium as set forth in claim 9, wherein said instructions causing said data processing system to measure a time quantum within a sampling time interval during which a central processing unit clock signal is active within a processor core of a central processing unit cause said data processing system to:

determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval; and

calculate said time quantum utilizing said total number of cycles and a period of said central processing unit clock signal.

13. The data processing system-readable medium as set forth in claim 12, further comprising a plurality of instructions which when executed cause said data processing system to:

periodically execute a utilization application, wherein said sampling time interval comprises a time interval between a first execution of said utilization application and a second execution of said utilization application.

14. The data processing system-readable medium as set forth in claim 12, further comprising a plurality of instructions which when executed cause said data processing system to:

periodically execute a system management interrupt handler, wherein said sampling time interval comprises a time interval between a first execution of said system management interrupt handler and a second execution of said system management interrupt handler.

15. The data processing system-readable medium as set forth in claim 13, wherein said instructions causing said data processing system to determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval cause said data processing system to:

increment a time-stamp counter for each cycle of said central processing unit clock signal that is applied to said processor core during said sampling time interval from an initial value to a final value; and

subtract said initial value of said time-stamp counter from said final value of said time-stamp counter to determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval.

16. The data processing system-readable medium as set forth in claim 15, further comprising a plurality of instructions which when executed cause said data processing system to:

read said initial value of said time-stamp counter in response to said first execution of said utilization application; and

read said final value of said time-stamp counter in response to said second execution of said utilization application.

18. The data processing system as set forth in claim 17, wherein said instructions causing said data processing system to determine a utilization of said central processing unit during said sampling time interval utilizing said time quantum cause said data processing system to calculate a ratio of said time quantum to said sampling time interval.

19. The data processing system as set forth in claim 17, wherein said instructions causing said data processing system to measure a time quantum within said sampling time interval during which said central processing unit clock signal is active within said processor core of said central processing unit cause said data processing system to:

determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval; and

calculate said time quantum utilizing said total number of cycles and a period of said central processing unit clock signal.

20. The data processing system as set forth in claim 19, further comprising a time-stamp counter to increment for each cycle of said central processing unit clock signal that is applied to said processor core during said sampling time interval from an initial value to a final value, wherein:

said instructions causing said data processing system to determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval cause said data processing system to subtract said initial value of said time-stamp counter from said final value of said time-stamp counter to determine a total number of cycles of said central processing unit clock signal that are applied to said processor core of said central processing unit during said sampling time interval.

17. A data processing system comprising:

a central processing unit to process data and execute instructions, said central processing unit including a processor core;

a clock generator to generate a central processing unit clock signal and to define a sampling time interval;

a memory to store a plurality of instructions which when executed by said central processing unit cause said data processing system to;

measure a time quantum within said sampling time interval during which said central processing unit clock signal is active within said processor core of said central processing unit; and

determine a utilization of said central processing unit during said sampling time interval utilizing said time quantum.