Power conservation apparatus having multiple power reduction levels dependent upon the activity of the computer system

• US 5,396,635 A
• Filed: 02/12/1993
• Issued: 03/07/1995
• Est. Priority Date: 06/01/1990
• Status: Expired due to Term

• Current Assignee: St Clair Intellectual Property Consultants Incorporated
• Original Assignee: Vadem Limited
• Inventors: Fung, Henry T. S.
• Primary Examiner(s): Bowler, Alyssa H.
• Assistant Examiner(s): HARRITY, JOHN E
• Application Number:
  US08/017,975
• Time in Patent Office: 753 Days
• Field of Search: 395/750, 395/800, 395/375
• US Class Current: 713/323
• CPC Class Codes: B01J 2219/00315 Microtiter plates
• CPC Class Codes: B01J 2219/00317 Microwell devices, i.e. having large numbers of wells
• CPC Class Codes: B01J 2219/00605 the compounds being directly bound or immobilised to solid supports
• CPC Class Codes: B01J 2219/00659 Two-dimensional arrays
• CPC Class Codes: B01J 2219/00686 Automatic
• CPC Class Codes: B01J 2219/00691 using robots
• CPC Class Codes: B01J 2219/00707 separated from the reactor apparatus
• CPC Class Codes: C40B 60/14 for creating libraries
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3209 Monitoring remote activity, e.g. over telephone lines or network connections
• CPC Class Codes: G06F 1/3215 Monitoring of peripheral devices
• CPC Class Codes: G06F 1/3221 of disk drive devices
• 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: 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 power conservation system in a computer system which includes a processing unit operating under control of an operating system. The computer system generates distinct call functions to the operating system where each call function is either in an active class or an idle class. The power conservation system has a plurality of states of operation including an ON state, a DOZE state, a SLEEP state and an OFF state. An activity monitor monitors the activity of the computer system and generating control signals for selecting one of the state of operation for the computer system. The activity monitor includes a storage for storing a call value for each distinct call function and activity threshold values for the various states of operation. The call values are weighted for the call functions whereby different call functions have a greater or lesser impact on the value of an activity level. The call value for each call function is retrieved when the call function is made to the operating system. The retrieved call values are sequentially accumulated to form an activity value which indicates the activity level of the computer system. A comparator compares the activity value with the threshold values and in response to the comparison generates a control signal to a power controller which selects the states of operation for the computer system, thereby regulating the power consumption of the computer system based on the activity of the computer system.

Claims

1. A power conservation system for use in a computer system wherein said computer system includes a processing unit which operates under control of an operating system, said computer system generating a plurality of distinct call functions to said operating system where each said call function is designated to be in either an active class or an idle class, said power conservation system comprising:

a plurality of states of operation including

an ON state wherein the power consumed by said computer system is unregulated by said power control means,

a DOZE state which decreases the power consumption to a first level,

a SLEEP state which decreases the power consumption from said first level to a second level, and

an OFF state wherein said computer system consumes no power;

an activity monitor for monitoring the activity of said computer system and for generating a plurality of control signals where each said control signal indicates a different activity state in said computer system, said activity monitor comprising;

a first monitor including;

storage means for storing activity threshold values for said computer system where said threshold values includes a positive idle value and a negative active value and for storing a call value for each said distinct call function where said call values are positive for said call functions in said idle class and negative for said call functions in said active class wherein said call values are weighted for said call functions in both said idle and active classes whereby different call functions have a greater or lesser impact on the value of the activity level when that call function is encountered by said operating system;

activity means for retrieving from said storage means said call value for each said call function when said call function is made to said operating system and including an accumulator means for sequential algebraically accumulating said call values to form an activity value as said call functions are made to said operating system whereby said activity value indicates the activity level of the computer system; and

comparison means for comparing said activity value with said idle value and said activity value and in response to said comparison generating control signals to place said computer system in said DOZE state or said SLEEP state when said activity value is greater than said idle value and to place said system in said ON state when said activity value is less than said active value; and

power control means coupled to said activity monitor for receiving said control signals and in response to said control signals selecting and operating under one of said plurality of states of operation thereby regulating the power consumption of said computer system based on the activity of said computer system.

2. The power conservation system of claim 1 wherein said plurality of states of operation of said power conservation system further comprises:

a STANDBY state which reduces said power consumption of said computer system from said second level to a third level.

3. The power conservation system of claim 2 where said computer system includes a power source means, a clock means for providing computer clock signals at clock frequencies, and a memory which is refreshed at a refresh frequency, said power control means further comprising:

a clock control unit coupled to said clock means for controlling the frequency of the computer clock signals as a function of said state of operation of said power control unit;

a power level unit coupled to said power source means for controlling the distribution of power within said computer system as a function of said state of operation of said power control means; and

a refresh control unit coupled to said memory unit for controlling the frequency of refreshing said memory unit in response to said state of operation of said power control means.

4. A power conservation system wherein said computer system including a processor and a bus for connecting said processing unit and one or more units within said computer system where each of said units are assigned a set of addresses within the computer system, said power conservation system comprising:

a plurality of states of operation including

an ON state wherein the power consumed by said computer system is unregulated by said power control means,

a DOZE state which decreases the power consumption to a first level,

a SLEEP state which decreases the power consumption from said first level to a second level,

a STANDBY state which reduces said power consumption of said computer system from said second level to a third level, and

an OFF state wherein said computer system consumes no power;

an activity monitor for monitoring the activity of said computer system and for generating a plurality of control signals where each said control signal indicates a different activity state in said computer system, said activity monitor comprising a second monitor connected to said bus and operating independently of said processing means, said second monitor including;

address means for generating an active signal upon detecting the occurrence of an address on said bus from one or more said address sets; and

timing means for measuring the period of time between successive active signals generated by said address means and for generating a first control signal when said period of time is equal to a first predetermined value, a second control signal when said period of time is equal to a second predetermined value after said first control signal has been generated, a third control signal when said period of time is equal to a third predetermined value after said second control signal has been generated and a fourth control signal when said period of time is equal to a fourth predetermined value after said third control signal has been generated, said timing means being reset in response to said active signal; and

a power control means connected to said second monitor for receiving said first, second, third and fourth control signals and said active signal and switching from said ON state to said DOZE state in response to said first control signal, from said DOZE state to said SLEEP state in response to said second control signal, from said SLEEP state to said STANDBY state in response to said third control signal, from said STANDBY state to said OFF state in response to said fourth control signal and from said DOZE and SLEEP states to said ON state in response to said active signal thereby regulating the power consumption of said computer system based on the activity of said computer system.

5. The power conservation system of claim 4 wherein said computer system includes a processing unit which operates under control of an operating system, said computer system generating a plurality of distinct call functions to said operating system where each said call function is designated to be in either an active class or an idle class, said activity monitor comprising,

a first monitor including;

storage means for storing a call value for each said distinct call function and activity threshold values for the computer system;

activity means for retrieving from said storage means said call value for each said call function when said call function is made to said operating system and for sequential accumulating said call values to forman activity value as said call functions are made to said operating system, said activity value being indicative of the activity level of the computer system; and

comparison means for comparing said activity value with said threshold values and in response to said comparison generating said control signals for causing said power control means to select or operate in either said ON state, said DOZE state or said SLEEP state.

6. The power management system of claim 5 wherein said first monitor comprises;

said threshold values stored in said storage means includes an idle value and an active value; and

said comparison means for comparing said activity value with said idle value and in response to said comparison generating control signals which will cause said power control unit to select and operate in either said DOZE state or said SLEEP state if said comparison indicated that the computer system activity level permitted said computer system to be placed in said DOZE state or said SLEEP state.

7. The power conservation system of claim 6 wherein:

said call values for said call functions are positive call values for said call functions in said idle class and negative call values for said call functions in said active class, and said idle value is a positive value and said active value is a negative value; and

said activity means includes accumulation means for generating said activity value by sequentially algebraically accumulating said calls values; and

said comparison means generating said control signals to cause said power control means to select and operate in said DOZE state or said SLEEP state when said activity value is greater than said idle value and generating said control signals to cause said power control means to select and operate in said ON state when said activity value is less than said active value, said control signals resetting said accumulation means to a predetermined value.

8. The power conservation system of claim 7 wherein said call values are weighted for said call functions in both said idle and active classes whereby different call functions have a greater or lesser impact on the value of the activity level when that call function is encounter by said operating system.