Nonintrusive monitoring of a computer system's downtime due to a supply power outage condition

• US 6,026,495 A
• Filed: 12/09/1997
• Issued: 02/15/2000
• Est. Priority Date: 12/09/1997
• Status: Expired due to Term

• Current Assignee: HTC Corporation
• Original Assignee: Compaq Computer Corporation (HP Inc.)
• Inventors: Gaudet, Rene R., Yee, Peter M., Van Cleve, Robert, Lacombe, John S.
• Primary Examiner(s): Sheikh, Ayaz R.
• Assistant Examiner(s): PANCHOLI, JIGAR K
• Application Number:
  US08/987,625
• Time in Patent Office: 798 Days
• Field of Search: 713/300, 713/340, 714/14, 714/22, 709/223, 709/224
• US Class Current: 713/340
• CPC Class Codes: G06F 11/3419 by assessing time
• CPC Class Codes: G06F 2201/88 Monitoring involving counting

Abstract

A nonintrusive monitoring system is used to determine the onset and duration times of an electrical power outage-caused down condition of a computer without requiring a pre-power outage polling of a running component of the computer and thereby degrading computer system performance. In response to a supply power outage the monitoring system switches on a battery-powered counter device, representatively a digital counter or a real time clock, and then switches the counter device back off in response to resumption of power supply to the computer. A software portion of the monitoring system then detects the count value of the counter device, and utilizes the count value to compute the onset and duration times of the previous power outage. Using an alternative nonintrusive technique, the monitoring system permits the counter device to run during power supply to the computer, while using the computer system clock to generate periodic time stamps, and disables the counter device during computer supply power outages. Upon resumption of supply power to the computer, the monitoring system compares the time stamp information to the count value to determine the onset and duration times of the previous supply power outage.

Claims

1. A computer system comprising:

a CPU unit adapted to receive electrical operating power from a source thereof, said CPU unit including a processor and a data storage device from which data may be retrieved by said processor; and

a monitoring system for monitoring CPU power outages, said monitoring system including;

a counter device having an on state during which it generates an incrementing count value, and an off state during which said count value remains constant,

first means, responsive to a CPU unit operating power outage, for changing the state of said counter device from a selected first one of said on and off states to the other of said on and off states, and

second means, responsive to a resumption in CPU unit operating power supply, for changing the state of said counter device back to said first one of said on and off states, determining the count value of said counter device, and using the determined count value to generate CPU unit power outage downtime information.

2. The computer system of claim 1 wherein said power outage downtime information includes the onset time of the previous power outage.

3. The computer system of claim 1 wherein said power outage downtime information includes the duration time of the previous power outage.

4. The computer system of claim 3 wherein said power outage downtime information further includes the onset time of the previous power outage.

5. The computer system of claim 1 wherein said counter device includes a digital counter portion.

6. The computer system of claim 1 wherein said counter device is a software-controlled digital counter.

7. The computer system of claim 1 wherein said counter device includes a real time clock portion.

8. The computer system of claim 1 wherein said counter device is a software-controlled real time clock.

9. The computer system of claim 1 wherein said first one of said on and off states of said counter device is said off state thereof.

10. The computer system of claim 9 wherein:

said counter device is electrically operable, and

said first means include power supply means for supplying electrical power to said counter device only during an outage of electrical operating power to said CPU unit.

11. The computer system of claim 1 wherein:

said CPU unit has a system clock operative to generate a time stamp subsequent to said resumption in CPU unit operating power supply, and

said second means are operative to use the determined count value to generate said CPU power outage downtime information by correlating in a predetermined manner the determined count value with the time value of said time stamp.

13. The computer system of claim 1 wherein said first one of said on and off states of said counter device is said on state thereof.

12. A computer system comprising:

a CPU unit adapted to receive electrical operating power from a source thereof, said CPU unit including a processor and a data storage device from which data may be retrieved by said processor; and

a monitoring system for monitoring CPU power outages, said monitoring system including;

an electrically operable counter device having an on state during which it generates an incrementing count value, and an off state during which said count value remains constant,

first means, responsive to a CPU unit operating power outage, for changing the state of said counter device from said on state to said off state, said first means including power supply means for supplying electrical power to said electrically operable counter device only during an outage of electrical operating power to said CPU unit, said power supply means including;

a battery coupled to said counter device for supplying electrical operating power thereto, and

switch means for preventing said battery from supplying electrical operating power to said counter device while electrical operating power from said source thereof is being supplied to said CPU unit, and permitting said battery to supply electrical operating power to said counter device in response to an outage of electrical operating power to said CPU unit, and

second means, responsive to a resumption in CPU unit operating power supply, for changing the state of said counter device back to said on state, determining the count value of said counter device, and using the determined count value to generate CPU unit Dower outage downtime information.

14. Computer apparatus comprising:

a CPU unit adapted to receive electrical operating power from a source thereof, said CPU unit being in an operating state during receipt of said electrical operating power, and in a power outage state during an outage of said electrical operating power, said CPU unit further having at least one nonvolatile storage device; and

a nonintrusive power outage monitoring system for generating CPU unit power outage downtime information without polling any of said at least one nonvolatile storage device during said operating state of said CPU unit, said monitoring system being operative to generate an incrementing count value during a selected one of said operating and power outage states and then determine said count value and use it to compute and generate said downtime information during a subsequent one of said operating and power outage states.

15. The computer apparatus of claim 14 wherein:

said CPU unit has a system clock operative to generate a time stamp subsequent to said CPU unit being returned to said operating state from said power outage state, and

said nonintrusive power outage monitoring system is operative to compute and generate said downtime information by correlating in a predetermined manner the determined count value with the time value of said time stamp.

16. A computer system comprising:

a CPU unit adapted to receive electrical operating power from a source thereof, said CPU unit including a processor and a data storage device from which data may be retrieved by said processor; and

a monitoring system for monitoring CPU power outages, said monitoring system including;

an electrically operable, software-controlled counter device having an on state during which it generates an incrementing count value, and an off state during which said count value remains constant,

first means, responsive to a CPU unit operating power outage, for changing the state of said counter device from said off state to said on state, said first means including power supply means for supplying electrical power to said counter device only during an outage of electrical operating power to said CPU unit, and

second means, responsive to a resumption in CPU unit operating power supply, for changing the state of said counter device back to said off state, determining the count value of said counter device, and using the determined count value to generate CPU unit power outage downtime information indicative of the onset and duration times of the previous power outage,

said power supply means including;

a battery coupled to said counter device for supplying electrical operating power thereto, and

switch means for preventing said battery from supplying electrical operating power to said counter device while electrical operating power from said source thereof is being supplied to said CPU unit, and permitting said battery to supply electrical operating power to said counter device in response to an outage of electrical operating power to said CPU unit.

17. The computer system of claim 16 wherein said counter device is an electrically operable software-controlled digital counter.

18. The computer system of claim 16 wherein said counter device is an electrically operable software-controlled real time clock.

19. A method of monitoring electrical power supply outages to a computer, said method comprising the steps of:

providing a counter device having an on state during which it generates an incrementing count value, and an off state during which said count value remains constant;

changing the state of said counter device from a selected first one of said on and off states to the other of said on and off states in response to a CPU unit electrical supply outage; and

changing the state of said counter device back to said first one of said on and off states, determining the count value of said counter device, and then using the determined count value to generate CPU unit power outage downtime information, in response to a resumption in CPU unit electrical power supply.

20. The method of claim 19 wherein said step of using the determined count value to generate CPU unit power outage downtime information includes the step of generating data indicative of the onset and duration times of the previous power outage.

21. The method of claim 19 wherein said counter device is electrically powerable and said state-changing steps are performed by supplying electrical power to said counter device only during an outage of electrical power supply to the computer.

22. The method of claim 19 wherein:

said method further comprises the step of providing a system clock operative to generate a time stamp subsequent to said resumption in CPU unit electrical power supply, and

said step of using the determined count value to generate CPU unit power outage downtime information includes the step of correlating in a predetermined manner the determined count value with the time value of said time stamp.

23. For use with a computer having at least one nonvolatile storage device incorporated therein, the computer being in an operating state during receipt of electrical operating power from a source thereof, and in a power outage state during an outage of the electrical operating power, a nonintrusive method of monitoring electrical power supply outages to the computer without polling any of said at least one nonvolatile storage device during the operating state of the computer, said method comprising the steps of:

generating an incrementing count value during a selected one of the operating and power outage states of the computer, and then

determining the count value, and using it to compute and generate said downtime information, during a subsequent one of said operating and power outage states of the computer.

24. The method of claim 23 wherein said generating step is performed using a software-controlled counter device.

25. The method of claim 24 wherein said generating step is performed using a software-controlled digital counter.

26. The method of claim 24 wherein said generating step is performed using a software-controlled real time clock.

27. The method of claim 23 wherein said generating step is performed during said operating state of said computer.

28. The method of claim 23 wherein said generating step is performed during said power outage state of the computer.

29. The method of claim 23 wherein said step of using the determined count value to compute and generate said downtime information includes the generation of data indicative of the onset and duration times of a power outage state of the computer.

30. The method of claim 23 wherein:

the computer has a system clock operative to generate a time stamp subsequent to the return of the computer to its operating state from its power outage state, and

said step of using the determined count value includes the step of correlating in a predetermined manner the determined count value with the time value of said time stamp.