System, method, and architecture for dynamic server power management and dynamic workload management for multi-server environment

Abstract

Network architecture, computer system and/or server, circuit, device, apparatus, method, and computer program and control mechanism for managing power consumption and workload in computer system and data and information servers. Further provides power and energy consumption and workload management and control systems and architectures for high-density and modular multi-server computer systems that maintain performance while conserving energy and method for power management and workload management. Dynamic server power management and optional dynamic workload management for multi-server environments is provided by aspects of the invention. Modular network devices and integrated server system, including modular servers, management units, switches and switching fabrics, modular power supplies and modular fans and a special backplane architecture are provided as well as dynamically reconfigurable multi-purpose modules and servers. Backplane architecture, structure, and method that has no active components and separate power supply lines and protection to provide high reliability in server environment.

I claim:  
     
         1 . A computer system comprising: 
 a plurality of server computers each having at least one processor and an activity monitor identifying a level of activity indicator for said at least one processor;    each of said server computers being operable in: (i) a first mode having a first maximum performance level and a first power consumption rate, (ii) a second mode having a second maximum performance level lower than said first maximum performance level and a second power consumption rate lower than said first power consumption rate, and (iii) a third mode having a third maximum performance level lower than said second maximum performance level and a third power consumption rate lower than said second power consumption rate; and    a power manager: (i) coupled to each of said server computers and receiving said level of activity information from each of said plurality of computers; (ii) analyzing said plurality of received level of activity information; (iii) determining an operating mode for each of said server computers selected from said first mode, second mode, and third mode based on said analyzed activity information and predetermined policies; and (iv) generating commands to each of said plurality of server computers directing each of said plurality of server computers to operate in said determined operating mode.    
     
     
         2 . A computer system comprising: 
 a plurality of computers each having at least one processor and an activity monitor identifying a level of activity indicator for said at least one processor;    each of said computers being operable in: (i) a first mode having a first maximum performance level and a first power consumption rate, and (ii) a third mode having a third maximum performance level lower than said first maximum performance level and a third power consumption rate lower than said first power consumption rate; and    a power manager: (i) coupled to each of said computers and receiving said level of activity information from each of said plurality of computers; (ii) analyzing said plurality of received level of activity information; (iii) determining an operating mode for each of said computers selected from said first mode and third mode based on said analyzed activity information and predetermined policies; and (iv) generating commands to each of said plurality of computers directing each of said plurality of computers to operate in said determined operating mode.    
     
     
         3 . The computer system in  claim 2 , wherein: 
 each of said computers further being operable in (iii) a second mode having a second maximum performance level intermediate between said first maximum performance level and said third maximum performance level and a second power consumption rate intermediate between said first power consumption rate and said third power consumption rate; and    said power manager further determining an operating mode for each of said computers selected from said first mode, said second mode, and said third mode based on said analyzed activity information and said predetermined policies.    
     
     
         4 . The computer system in any of claims  2 , wherein: said computers comprise servers.  
     
     
         5 . The computer system in any of claims  2  further comprising a power manager computer providing said power manager.  
     
     
         6 . The computer system in any of claims  2  wherein a selected one of said plurality of computers designated as a master providing said power manager.  
     
     
         7 . The computer system in any of claims  2 , wherein said activity monitor comprises an activity monitor that monitors an activity selected from the set of activities consisting of: a program application layer activity, a network layer activity, a physical layer activity, and combinations thereof.  
     
     
         8 . The computer system in  claim 7 , wherein said application layer activity monitor comprises monitoring use of a port address within said computers.  
     
     
         9 . The computer system in clam  7 , wherein said network layer activity monitor comprises monitoring use of a TCP/IP protocol within said computers.  
     
     
         10 . The computer system in clam  7 , wherein said physical layer activity monitor comprises monitoring the execution of idle threads within said computers.  
     
     
         11 . The computer system in clam  7 , wherein said physical layer activity monitor comprises monitoring counting activities having particular activity values within said computers.  
     
     
         12 . The computer system in clam  3 , wherein: 
 said first mode operation is characterized by operating said processor at a first processor clock frequency and a first processor core voltage, said second mode operation is characterized by operating said processor at a second processor clock frequency and a second processor core voltage, and said third mode operation is characterized by operating said processor at a third processor clock frequency and a third processor core voltage;    said second mode of operation being further characterized in that said second processor clock frequency and said second processor core voltage in combination consuming less power than said first processor clock frequency and said first processor core voltage in combination, and said third processor clock frequency and said third processor core voltage in combination consuming less power than said second processor clock frequency and said second processor core voltage in combination.    
     
     
         13 . The computer system in clam  12 , wherein: said third processor clock frequency is less than said second processor clock frequency which is less than said first processor clock frequency.  
     
     
         14 . The computer system in clam  13 , wherein: said second processor core voltage is less than said first processor core voltage.  
     
     
         15 . The computer system in clam  14 , wherein: said third processor core voltage is less than said second processor core voltage.  
     
     
         16 . The computer system in clam  12 , wherein: said third processor clock frequency is less than said second processor clock frequency which is less than said first processor clock frequency; and said second processor core voltage is less than said first processor core voltage.  
     
     
         17 . The computer system in  claim 2 , wherein: 
 each of said computers further being operable in (iii) a second mode having a second maximum performance level intermediate between said first maximum performance level and said third maximum performance level and a second power consumption rate intermediate between said first power consumption rate and said third power consumption rate; and    each said computer including a local power manager determining an operating mode for itself selected from said first mode and said second mode based on processor internal activity information.    
     
     
         18 . The computer system in  claim 17 , wherein: said processor internal activity information comprising idle thread execution information.  
     
     
         19 . The computer system in  claim 17 , wherein a transition from said first mode to said second mode is controlled locally within each said computer; and a transition from either said first mode or said second mode to said third mode are controlled globally by said power manager.  
     
     
         20 . The computer system in  claim 19 , wherein a transition from said second mode to said first mode is controlled locally within each said computer; and a transition from said third mode to either said first mode or said second mode is controlled globally by said power manager.  
     
     
         21 . The computer system in  claim 12 , wherein said third processor clock frequency is substantially zero or the third processor clock is turned off.  
     
     
         22 . The computer system in  claim 12 , wherein said commands are generated and directed to said computers only when required to change an operating mode of said computers.  
     
     
         23 . The computer system in any of claims  2  or  3 , wherein said third mode is characterized by maintaining a processor core voltage to maintain processor state.  
     
     
         24 . A computer system comprising: 
 a plurality of server computers each having at least one processor and an activity monitor identifying a level of activity for said at least one processor, said activity monitor comprising an activity monitor that monitors an activity selected from the set of activities consisting of: a program application layer activity, a network layer activity, a physical layer activity, and combinations thereof;    each of said server computers being operable in: (i) a first mode having a first maximum performance level and a first power consumption rate, (ii) a second mode having a second maximum performance level lower than said first maximum performance level and a second power consumption rate lower than said first power consumption rate, and (iii) a third mode having a third maximum performance level lower than said second maximum performance level and a third power consumption rate lower than said second power consumption rate; and    a power manager operative in a separate power manager computer: (i) coupled to each of said server computers and receiving said level of activity information from each of said plurality of computers; (ii) analyzing said plurality of received level of activity information; (iii) determining an operating mode for each of said server computers selected from said first mode, second mode, and third mode based on said analyzed activity information; and (iv) generating commands to each of said plurality of server computers directing each of said plurality of server computers to operate in said determined operating mode;    said first mode operation is characterized by operating said processor at a first processor clock frequency and a first processor core voltage, said second mode operation is characterized by operating said processor at a second processor clock frequency and a second processor core voltage, and said third mode operation is characterized by operating said processor at a third processor clock frequency and a third processor core voltage;    said second mode of operation being further characterized in that said second processor clock frequency is lower than said first processor clock frequency and said second processor core voltage is lower than said first processor core voltage so that in combination consuming less power than in said first mode, and said third processor clock frequency is lower than said second processor clock frequency and said third processor core voltage is no greater than said second processor core voltage so that in combination consuming less power than in said second mode; and    a transition from said first mode to said second mode is controlled locally within each said computer; and a transition from either said first mode or said second mode to said third mode are controlled globally by said power manager.    
     
     
         25 . A method of operating computer system having a plurality of server computers, each server computer including at least one processor, and each computer being operable in a first mode having a first maximum performance level and a first power consumption rate, and a third mode having a third maximum performance level lower than said first maximum performance level and a third power consumption rate lower than said first power consumption rate; said method comprising: 
 monitoring activity within said computers and identifying a level of activity for said at least one processor within said computers;    analyzing said plurality of level of activity information;    determining an operating mode for each of said computers selected from said first mode and third mode based on said analyzed activity information; and    generating commands to each of said plurality of computers directing each of said plurality of computers to operate in said determined operating mode.    
     
     
         26 . The method in  claim 25 , wherein each of said computers further being operable in a second mode having a second maximum performance level intermediate between said first maximum performance level and said third maximum performance level and a second power consumption rate intermediate between said first power consumption rate and said third power consumption rate; and said determining an operating mode further comprising determining an operating mode for each of said computers selected from said first mode, said second mode, and said third mode based on said analyzed activity information.  
     
     
         27 . The method of  claim 26 , wherein a transition from said first mode to said second mode is controlled locally within each said computer; and a transition from either said first mode or said second mode to said third mode are controlled globally by said power manager.  
     
     
         28 . The method of  claim 27 , wherein a transition from said second mode to said first mode is controlled locally within each said computer; and a transition from said third mode to either said first Mode or said second mode is controlled globally by said power manager.  
     
     
         29 . A system as in  claim 12 , wherein at least one of a processor clock frequency and a processor operating voltage is reduced in response to said indicator to thereby reduce power consumed by said processor and by said server computer.  
     
     
         30 . A system as in  claim 12 , wherein the processor clock frequency is reduced in response to said indicator to thereby reduce power consumed by said processor and by said server.  
     
     
         31 . A system as in  claim 12 , wherein said indicator comprises a measured decrease in server load.  
     
     
         32 . A system as in  claim 12 , wherein said indicator comprises a predicted decrease in server load.  
     
     
         33 . A system as in  claim 12 , wherein said indicator comprises a measured decrease in processor tasking.  
     
     
         34 . A system as in  claim 12 , wherein said indicator comprises a predicted decrease in processor tasking.  
     
     
         35 . A system as in  claim 32 , wherein said predicted decrease in server load is a prediction based at least in part on time of day.  
     
     
         36 . A system as in  claim 32 , wherein said predicted decrease in server load is a prediction based at least in part on a quality of service requirement.  
     
     
         37 . A system as in  claim 32 , wherein said predicted decrease in processor tasking is a prediction based at least in part on time of day.  
     
     
         38 . A system as in  claim 32 , wherein said predicted decrease in processor tasking is a prediction based at least in part type of content to be processed.  
     
     
         39 . A system as in  claim 32 , wherein said predicted decrease in server loading is a prediction based at least in part type of content to be served.  
     
     
         40 . A system as in  claim 32 , wherein the manner of said prediction is further based on the content served by the server.  
     
     
         41 . A system as in  claim 12 , wherein the majority of content served by said server computer comprises web pages.  
     
     
         42 . A system as in  claim 12 , wherein the majority of content served by said server computer comprises streaming video.  
     
     
         43 . A system as in  claim 12 , wherein the majority of content served by said server computer comprises multi-media content.  
     
     
         44 . A system as in  claim 12 , wherein the majority of content served by said server comprises cached data.  
     
     
         45 . A system as in  claim 12 , wherein a processor operating voltage is reduced in response to said indicator to thereby reduce power consumed by said processor and by said server.  
     
     
         46 . A system as in  claim 12 , wherein a predetermined combination of processor core voltage and processor frequency are selected based on predetermined rules to satisfy a processor load requirement.  
     
     
         47 . A system as in  claim 46 , wherein said predetermined rules for selecting said predetermined combination of processor core voltage and processor frequency comprise a look-up-table (LUT) identifying processor frequency and processor core voltage with processor load handling capability.  
     
     
         48 . A system as in  claim 12 , wherein each processor has a processor load handling capability measured in instructions per second.  
     
     
         49 . A system as in  claim 12 , wherein each processor has a processor load handling capability is measured in bits served per second.  
     
     
         50 . A system as in  claim 12 , wherein the predetermined rules are different for different network device types.  
     
     
         51 . A system as in  claim 3 , wherein the predetermined policies include policies for identifying a non-linear relationship between processor performance and power consumption.  
     
     
         52 . A system as in  claim 3 , wherein power (P) consumed by a circuit in said processor is proportional to a capacitance (C) times the product of the switching frequency of the circuit (f) and the square of the circuit operating voltage (v 2 ) or P=Cfv 2 .  
     
     
         53 . A system as in  claim 52 , wherein switching frequency is substantially linear relative to power consumption, the load is non-linear relative to circuit performance, and the load is non-linear relative to power consumed by the circuit.  
     
     
         54 . A system as in  claim 53 , wherein the circuit comprises a processor and random access memory.  
     
     
         55 . A system as in  claim 3 , wherein the predetermined policy includes a policy for identifying a substantially linear relationship between processor performance and power consumption.  
     
     
         56 . A system as in  claim 3 , wherein said processor provides processing for a web server and said web server has a substantially linear relationship between web page server loading an power consumed in serving said web pages.  
     
     
         57 . A system as in  claim 3 , wherein a quality-of-service (QoS) is first established, and a processor performance is established based on predetermined policies that select a processor clock frequency, and a minimum processor core voltage is selected to match said selected processor clock frequency; and wherein the established processor performance is used to control an operating mode.  
     
     
         58 . A system as in  claim 12 , further including a processor core voltage control circuit receiving voltage control signals and increasing or decreasing said processor core voltage in response to said receipt.  
     
     
         59 . A system as in  claim 5   8 , wherein said processor core voltage control circuit provides a direct-current voltage to a Vcc supply terminal of said processor.  
     
     
         60 . A system as in  claim 12 , wherein said activity level indicator includes an indicator of the number of idle threads executed in said processor, and reduction of processor power consumption is initiated based on detection of the execution of an idle thread by said processor.  
     
     
         61 . A system as in  claim 60 , wherein upon detection of execution of said idle thread, the processor frequency is reduced as compared to a maximum processor clock frequency.  
     
     
         62 . A system as in  claim 61 , wherein said processor frequency reduction is a reduction by a factor of a power of two.  
     
     
         63 . A system as in  claim 61 , wherein said processor clock frequency is reduced to zero.  
     
     
         64 . A system as in  claim 61 , wherein said processor frequency is reduced to an integral multiple of a maximum processor clock frequency.  
     
     
         65 . A system as in  claim 60 , wherein upon detection of execution of said idle thread, the processor frequency is reduced as compared to a maximum processor clock frequency and the processor core voltage is reduced as compared to a maximum processor core voltage.  
     
     
         66 . A system as in  claim 60 , wherein said detection of execution of an idle thread initiated power reduction provides a real time adjustment to power consumption based on measured processor load requirements.  
     
     
         67 . A system as in  claim 57 , wherein said QoS initiated power reduction provides a preset adjustment to power consumption based on predicted processor load requirements.  
     
     
         68 . A system as in  claim 57 , wherein said QoS requirement is adjusted on at least one of a time-of-day criteria, a day-of-week criteria, a seasonal criteria, and combinations thereof.  
     
     
         69 . A system as in  claim 57 , wherein said QoS requirement is adjusted based on criteria selected from the set consisting of: time-of-day, day-of-month, day-of week, month-of year, geographic location of requester, requester identity, requester account number, and combinations thereof.  
     
     
         70 . A system as in  claim 3 , wherein said computer comprises a network device selected from the set consisting of a server device, a computer node, monitor node, a switch, a management module, a server module, a power supply, a fan module, and combinations thereof.  
     
     
         71 . A system as in  claim 3 , wherein sid system further comprises a switching module, and said power manager receives activity indicators for said switching module and controls an operating mode of said switching module in response thereto.  
     
     
         72 . A system as in  claim 3 , wherein said computer comprises a server module that is power managed by adjusting processor performance to one or more of a predicted processor processing requirement and a measured processor processing requirement.  
     
     
         73 . A system as in  claim 72 , wherein said predicted processor processing requirement is a Quality of Service (QoS) based requirement, and said measured processor processing requirement comprises a substantially real-time measured processor processing requirement.  
     
     
         74 . A system as in  claim 73 , wherein said substantially real-time processor processing requirement comprises an idle thread execution detection and response thereto.  
     
     
         75 . A system as in  claim 3 , wherein power (or energy) is conserved by controlling the computer based on a control procedure algorithm to enter a first level of power (energy) saving by adjusting the performance of the processor within the computer to substantially match the computer processor loading demand.  
     
     
         76 . A system as in  claim 3 , wherein power (or energy) is conserved by controlling the plurality of computers in aggregate based on a control procedure algorithm and said policy to enter selected levels of power (energy) saving by adjusting the performance of the processors within the computers to one of the first mode, second mode, and third mode to substantially match the aggregate computer processor loading demands.  
     
     
         77 . A system as in  claim 2 , wherein said power manager includes a control procedure algorithm implemented as software to implement a power on demand control procedure.  
     
     
         78 . A system as in  claim 3 , wherein each computer is configurable as a particular type of network device.  
     
     
         79 . A system as in  claim 3 , wherein said computer is configured as a network device selected from the set consisting of a web server, a streaming media server, a cache server, a file server, an application server, and a router.  
     
     
         80 . A system as in  claim 3 , wherein at least selected ones of said computers are configurable as a combination type of network device, and wherein said network device configured in said computer node is a network device selected from the set consisting of a web server, a streaming media server, a cache server, a file server, an application server, a router, and combinations thereof.  
     
     
         81 . A system as in  claim 80 , wherein said network device is reconfigurable at any time based on types of activities detected within the network to which the network device is or may be connected.  
     
     
         82 . A system as in  claim 3 , wherein at least one of said computers comprises a network device and the activity monitor for said network device comprises a network activity monitor that detects the types of activities present on a network to which said activity monitor is coupled.  
     
     
         83 . A system as in  claim 82 , wherein said types of activities present on a network to which said activity monitor is coupled that are monitored by said activity monitor include volume of web pages served, volume of streaming media served, volume of files served, volume of applications served, volume of cached data served, amount of network traffic routed, and combinations thereof.  
     
     
         84 . A system as in  claim 81 , wherein said reconfiguration of network device is initiated by any network device including the same network as is being reconfigured.  
     
     
         85 . A system as in  claim 6 , wherein said reconfiguration of a network device is initiated by any computer that has been designated as a master computer.  
     
     
         86 . A system as in  claim 6 , wherein any computer may be designated as the master node.  
     
     
         87 . A system as in  claim 86 , wherein a particular computer is designated as a master on the basis of its position within a chassis.  
     
     
         88 . A system as in  claim 86 , wherein a particular computer node is designated as a master node on the basis of the order of power-up or boot completion.  
     
     
         89 . A system as in  claim 86 , wherein reconfiguration of said computer comprises altering the software and/or firmware instructing said computer.  
     
     
         90 . A system as in  claim 86 , wherein reconfiguration of said computer comprises altering the data organization of a data storage device integral with or coupled to said computer.  
     
     
         91 . A system as in  claim 86 , wherein said data storage device comprises a hard disc drive based RAID storage array and altering said data organization comprises altering rad configuration of said data to provide better performance for the type of data being served.  
     
     
         92 . A system as in  claim 81 , wherein said reconfiguration of a computer is initiated by a management module network device.  
     
     
         93 . A system as in  claim 3 , wherein a plurality of computers of the same type are grouped together and treated as a single network device.  
     
     
         94 . A system as in  claim 93 , wherein said group of network devices treated as a single network device is managed and controlled as a single network device.  
     
     
         95 . A system as in  claim 93 , wherein said group of network devices treated as a single network device is power managed as a single network device.  
     
     
         96 . A system as in  claim 93 , wherein said group of network devices treated as a single network device is monitored as a single network device.  
     
     
         97 . A system as in  claim 93 , wherein said plurality of grouped network devices are electrically coupled via a backplane bus and the logical grouping of the plurality of network devices into a single logical network device is performed under control of software.  
     
     
         98 . A system as in  claim 97 , wherein said software executes within a processor and memory associated within each network device.  
     
     
         99 . A system as in  claim 93 , wherein said plurality of network devices each comprise a server group.  
     
     
         100 . A system as in  claim 93 , wherein said plurality of network devices each comprise a computer server module.  
     
     
         101 . A system as in  claim 100 , wherein each computer server module is configured as a computer server module selected from the group consisting of a web server, a streaming media server, a cache server, a file server, an application server, a router, and combinations thereof.  
     
     
         102 . A system as in  claim 97 , wherein the activity associated with each computer within a grouped logical network device may be monitored individually.  
     
     
         103 . A system as in  claim 97 , wherein the network activity associated with all or any subset of physical network device within a grouped logical network device may be monitored as a composite or in aggregate.  
     
     
         104 . A system as in  claim 1 , wherein grouping is accomplished by aggregating all of the activity in each computer and directing each computer in said logical group to operate at the same operating mode.  
     
     
         105 . A system as in  claim 3 , wherein over a period of time said system will have sufficient over capacity that some of said computers will be directed to operate in said third mode, said policy taking into account the amount each of said computers have historically spent operating in at least one of said first, second, or third mode and selecting a computer to operate in said third mode based on historical data.  
     
     
         106 . A system as in  claim 105 , wherein said computer selected to operate in said third mode is a computer that has the smallest cumulative duration operating in said third mode amongst the plurality of computers.  
     
     
         107 . A system as in  claim 105 , wherein said computer selected to operate in said third mode is randomly selected from amongst the plurality of computers.  
     
     
         108 . A system as in  claim 105 , wherein said computer selected to operate in said third mode is rotated sequentially amongst the plurality of computers.  
     
     
         109 . A system as in  claim 7 , wherein at the physical level the number of processor idle threads executed within a predetermined period of time are measured to determine processor loading and the processor performance is adjusted to by altering the operating mode to substantially match the level of processor loading.  
     
     
         110 . A system as in  claim 109 , wherein the substantial matching of processor performance to processor loading is performed with a predetermined amount of additional processor performance beyond that needed to match the processor loading.  
     
     
         111 . A system as in  claim 110 , wherein said predetermined amount of additional processor performance is between about one-percent and about five-percent additional performance.  
     
     
         112 . A system as in  claim 12 , wherein performance of a group of said computers configured as physical network devices forming a single logical device are power managed by reducing the performance and power consumption of each constituent physical device in predetermined equal increments or predetermined unequal increments.  
     
     
         113 . A system as in  claim 112 , wherein said unequal increments include placing one or more of said plurality of physical devices in said third mode operating mode.  
     
     
         114 . A system as in  claim 112 , wherein said unequal increments include placing one or more of said plurality of physical devices in said second mode operating mode.  
     
     
         115 . A system as in  claim 112 , wherein said unequal increments include placing one or more of said plurality of physical devices in a powered-off fourth mode.  
     
     
         116 . A system as in  claim 112 , wherein a composite performance of a logical network device is achieved by placing some physical network devices in said second mode and by placing others in a different mode.  
     
     
         117 . The computer system in  claim 2 , wherein said activity monitor comprises a network layer activity monitoring TCP/IP protocol data packets; and processor performance is incrementally lowered by said power manager using said mode control until data packets start dropping indicating that the processor performance is at the limit of adequacy and then increasing the processor performance by a specified increment to act as a safety margin to provide reliable communication of the packets.  
     
     
         118 . A system as in  claim 117 , wherein the specified increment is a one-percent to five percent increment.  
     
     
         119 . A system as in  claim 117 , wherein the specified increment is a 0.1 percent to 10 percent increment.  
     
     
         120 . The computer system in clam  7 , wherein said application layer activity monitor comprises monitoring use of a port address within said computers, said monitoring including counting or measuring a number of times a specific port address is being requested within a predetermined period of time, and in response to that counting or measurement, placing a sufficient amount of computer performance to meet the performance requirement for each application requesting the port address.  
     
     
         121 . A system as in  claim 120 , wherein said sufficient amount of network performance is provided by operating selected computer in a first predetermined performance having a predetermined power consumption and a second group of other selected physical network devices at a reduced second performance level having a power consumption lower than that of said first selected group.  
     
     
         122 . A system as in  claim 121 , wherein said first predetermined performance is a maximum performance and said second predetermined performance is a second level power saving mode.  
     
     
         123 . A system as in  claim 121 , wherein said first predetermined performance is a maximum performance and said second predetermined performance is a third level power saving mode.  
     
     
         124 . A system as in  claim 120 , wherein said measurement is determined via a SNMP agent.  
     
     
         125 . A system as in  claim 2 , wherein said power manager applies different policies for different application types including using different rules to determine and predict system performance requirements.  
     
     
         126 . A system as in  claim 125 , wherein said different application types comprise different server types.  
     
     
         127 . A system as in  claim 125 , wherein said different rules comprise different measurement procedures.  
     
     
         128 . A system as in  claim 125 , wherein said system performance requirements comprise processor performance requirements.  
     
     
         129 . A system as in  claim 125 , wherein said system performance requirements comprise server loading performance requirements.  
     
     
         130 . A system as in  claim 125 , wherein said application type comprises a network file server (NFS) application, said computer comprises a network server, and a processor within said computer operates at a processor clock frequency just sufficient to maintain a 100 Mbps ethernet connection.  
     
     
         131 . A system as in  claim 130 , wherein said processor clock frequency is less than about 300 MHz.  
     
     
         132 . The computer system in  claim 3 , wherein said activity indicator comprises a network quality of service indicator.  
     
     
         133 . A system as in  claim 3 , wherein power is conserved by controlling each computer node to enter one of said second mode or said third mode using one or more of a quality of service based predictive processor performance reduction and a activity based measured performance requirement.  
     
     
         134 . A system as in  claim 133 , wherein said activity based measured performance comprises an idle thread execution based activity measure.  
     
     
         135 . A system as in  claim 132 , wherein a plurality of said computers are organized as a single logical network device, and network device loading and QoS are measured for logical network device.  
     
     
         136 . A system as in  claim 132 , wherein within said single logical network device, at least some computers making up the logical network device enter the third mode while other of said physical network devices operate in one or more of said first and second modes.  
     
     
         137 . A system as in  claim 132 , wherein said computers can enter a third mode directly or indirectly from either said first mode or the second mode.  
     
     
         138 . A system as in  claim 3 , wherein when there is a requirement that one computer be placed in a lower power consumption mode, the computer selected for such lower power consumption is selected according to predetermined rules such that different computers are placed in lower power consumption mode each time such selection is required.  
     
     
         139 . A system as in  claim 138 , wherein said predetermined rules provide for random selection of one of the computers.  
     
     
         140 . A system as in  claim 138 , wherein said predetermined rules provide for cycling through the computers according to some predetermined ordering.  
     
     
         141 . A system as in  claim 140 , wherein said predetermined rules provide for cycling through the computers according to some predetermined ordering in which computers having the lowest time in service are preferentially selected for continued operation and network devices having the longest time in service are selected for reduced power operation.  
     
     
         142 . A system as in  claim 141 , wherein said reduced power operation includes being powered off.  
     
     
         143 . A system as in  claim 141 , wherein said reduced power operation includes being placed in a suspend mode.  
     
     
         144 . A system as in  claim 3 , wherein a computer placed in mode 3 is in a suspend state and may be woken up and placed in the first mode or the second mode by any one of a plurality of events including by a wake on LAN signal event.  
     
     
         145 . A system as in  claim 3 , wherein the transition from one power consumption mode to another power consumption mode is based on a procedure implemented in software.  
     
     
         146 . A system as in  claim 3 , wherein the transition from one power consumption mode to another power consumption mode is based on a procedure implemented in hardware and software.  
     
     
         147 . A system as in  claim 3 , wherein when there is need to operate fewer than all the computer, the particular computer or logical group of computers that is (are) turned off or placed in a reduced power consumption mode is cycled so that over time all of the network devices experience similar operating time histories.  
     
     
         148 . A system as in  claim 147 , wherein the computers include a non-volatile memory for storing operational history.  
     
     
         149 . A system as in  claim 148;  wherein said operational history includes a total operating time indicator.  
     
     
         150 . A system as in  claim 148 , wherein said operational history includes a time in service indicator.  
     
     
         151 . A system as in  claim 148 , wherein said operational history includes indicators for operational time at each operational mode.  
     
     
         152 . A system as in  claim 3 , wherein at least some of said computers include a mass storage device including a rotatable storage device.  
     
     
         153 . A system as in  claim 152 , wherein said rotatable mass storage device comprises a rotatable magnetic hard disk drive.  
     
     
         154 . A system as in  claim 152 , wherein said rotatable mass storage device comprises a rotatable optical disk drive.  
     
     
         155 . A system as in  claim 152 , wherein said rotatable mass storage device comprises a rotatable magneto-optical disk drive.  
     
     
         156 . A system as in  claim 152 , wherein said rotatable mass storage device is power managed by controlling the rotation of a motor rotating said rotatable device, wherein said disc drive is not rotated when a computer associated with said drive is in a mode 3 operating condition.  
     
     
         157 . A system as in  claim 3 , wherein said computers are configured as network server devices and a network load versus allocated network device performance profile is provided for each different type of network server device, and the performance level set for operation of said network device is established by reference to the profile.  
     
     
         158 . A system as in  claim 157 , wherein the profile is implemented as an analytical expression executed in software or firmware.  
     
     
         159 . A system as in  claim 157 , wherein the profile is implemented as a piecewise linear expression executed in software or firmware.  
     
     
         160 . A system as in  claim 157 , wherein the profile is implemented as a look-up-table stored in a memory.  
     
     
         161 . A system as in  claim 3 , wherein at least one of said computers comprises a network server device and said activity monitoring for said network server device comprises a monitoring or either said network device load or the network device quality of service (QoS); and wherein said monitoring is performed by said activity monitor or by a separate management computer, or both.  
     
     
         162 . A system as in  claim 3 , wherein said system includes at least one temperature sensor within an enclosure holding said computers for monitoring and reporting the temperature proximate the sensor to a computers configured to monitor said temperature.  
     
     
         163 . A system as in  claim 3 , wherein said system includes a plurality of temperature sensors within said enclosure reporting to one or more network devices.  
     
     
         164 . A system as in  claim 163 , wherein said plurality of temperature sensors are spatially distributed to provide temperature monitoring of different network devices within said enclosure.  
     
     
         165 . A system as in  claim 163 , wherein said plurality of temperature sensors are spatially distributed to provide temperature monitoring of different network devices and power supplies within said enclosure.  
     
     
         166 . A system as in  claim 162 , wherein when the temperature sensed by a temperature sensor is within a predetermined magnitude relationship of a first predetermined value at least one computer is transitioned to a lower power consumption state.  
     
     
         167 . A system as in  claim 166 , wherein when the temperature sensed by a temperature sensor is within a predetermined magnitude relationship of a second predetermined value at least one computer is transitioned to a powered off state.  
     
     
         168 . A system as in  claim 162 , wherein the operational mode of at least one computer is reduced to a lower power consuming and heat dissipating state in response to a temperature sensor reporting a temperature greater than or equal to a predetermined value.  
     
     
         169 . A system as in  claim 162 , wherein after said power consumption operating mode has been lowered permitting said computer to be operated at a higher power consuming state when the temperature sensed is below a predetermined temperature value, said lower temperature value being selected to provide hysteresis and prevent oscillation between higher power state and lower powered state.  
     
     
         170 . A system as in  claim 166 , wherein the lower power consumption state is achieved by lowering the clock frequency of the processor, the clock frequency of a bus coupling a processor to other components, or the operating voltage of the processor or other components.  
     
     
         171 . A system as in  claim 166 , wherein the particular network device that is transitioned to a lower power consumption state is selected based on predetermined rules.  
     
     
         172 . A system as in  claim 171 , wherein said predetermined rules include a quality of service indicator.  
     
     
         173 . A system as in  claim 172 , wherein additional computer devices are sent to lower energy consuming modes if the temperature remains above a predetermined temperature value.  
     
     
         174 . A system as in  claim 3 , wherein power consumption within said system is reduced by adjusting the number and motor speed of cooling fans responsible for cooling said computer.  
     
     
         175 . A system as in  claim 3 , wherein a plurality of cooling fans are provided and operate under control of said power manager that controls each fan to provide cooling at the rate and location desired to maintain said computers within a predetermined temperature range.  
     
     
         176 . A system as in  claim 3 , wherein said plurality of computers are disposed within a common enclosure and said system further comprising a plurality of temperature sensors and a plurality of cooling devices are also disposed within said enclosure, said plurality of temperature sensors communicating a temperature signal to a temperature control means and said control means adjusting the on/off status and operational parameters of the cooling units to extract heat according to predetermined rules.  
     
     
         177 . A system as in  claim 176 , wherein said power manager comprises said temperature control means.  
     
     
         178 . A system as in  claim 176 , wherein one of said computers within said enclosure comprises said temperature control means.  
     
     
         179 . A system as in  claim 2 , wherein said system further includes a plurality of power supplies and said power supplies are controlled to maintain a required power output level and operate said power supplies at a preferred efficiency.  
     
     
         180 . A system as in  claim 179 , wherein only selected ones of said plurality of power supplies are operated.  
     
     
         181 . A system as in  claim 179 , wherein multiple ones of said power supplies are operated but each is operated at less than rated power output capacity.  
     
     
         182 . A system as in  claim 3 , wherein the temperature of said system is moderated by motor driven cooling fans and wherein a rotational speed of said motor drive cooling is adjusted to maintain a predetermined temperature range proximate a temperature sensor.  
     
     
         183 . A system as in  claim 3 , wherein the rotational speed of a motor drive cooling is adjusted to maintain a predetermined temperature range within an enclosure.  
     
     
         184 . A power-conservative multi-node network device, comprising: 
 an enclosure having a power supply and a back-plane bus;    a plurality of hot-pluggable node devices in the form of printed circuit (PC) cards adapted for connection with said back-plane buss; and    each said node device being reconfigurable in substantially real-time to adapt to changing conditions on the network.    
     
     
         185 . The network device in  claim 184 , wherein said plurality of hot-pluggable node devices comprise up to sixteen node devices.  
     
     
         186 . The network device in  claim 184 , wherein each of said node devices includes power saving control features.  
     
     
         187 . A computer program product for use in conjunction with a computer system having a plurality of server computers, each server computer including at least one processor, and each computer being operable in a first mode having a first maximum performance level and a first power consumption rate, and a third mode having a third maximum performance level lower than said first maximum performance level and a third power consumption rate lower than said first power consumption rate, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism, comprising: 
 a program module that directs at least one computer, to function in a specified manner, the program module including instructions for: 
 monitoring activity within said computers and identifying a level of activity for said at least one processor within said computers;  
 analyzing said plurality of level of activity information;  
 determining an operating mode for each of said computers selected from said first mode and third mode based on said analyzed activity information; and  
 generating commands to each of said plurality of computers directing each of said plurality of computers to operate in said determined operating mode.  
   
     
     
         188 . The computer program product of  claim 187 , wherein each of said computers further being operable in a second mode having a second maximum performance level intermediate between said first maximum performance level and said third maximum performance level and a second power consumption rate intermediate between said first power consumption rate and said third power consumption rate; and said determining an operating mode further comprising determining an operating mode for each of said computers selected from said first mode, said second mode, and said third mode based on said analyzed activity information.  
     
     
         189 . The computer program product of  claim 188 , wherein a transition from said first mode to said second mode is controlled locally within each said computer; and a transition from either said first mode or said second mode to said third mode are controlled globally by said power manager.  
     
     
         190 . The computer program product of  claim 189 , wherein a transition from said second mode to said first mode is controlled locally within each said computer; and a transition from said third mode to either said first mode or said second mode is controlled globally by said power manager.