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marcoland · 22-03-2006, 20:56

Scaricabile da qui http://download.microsoft.com/downlo...%20Control.doc

Parameters to P-state policy
Several parameters to Windows processor performance state controls are configurable via registry keys.

These keys are provided with the intent that OEMs and system designers
may tune the performance of Windows processor power management features
to best suit specific platform designs, and allow adjustment to help
achieve maximum battery life and realize the best system performance.
NOTE: These parameters are statically adjustable; that is, they are read once during the kernel initialization code. Adjustments made to these values will not take place until the next system reboot.
The following registry keys are found in:
KEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session
Manager\Throttle (I VALORI SONO QUELLI DEFAULT)

PerfTimeDelta > Hardware Transition Latency > This value influences the frequency with which the OS will re-evaluate appropriate performance state in the idle loop.
PerfCriticalTimeDelta > 300000 (300ms) > An application may use so much of the CPU’s time that the OS will never enter the idle loop. In order to make sure that we will increase the performance of the CPU in this situation, the processor power policy manager sets a timer that will interrupt the application. This value influences the time that must pass before the timer will fire.
PerfIncreasePercentModifier > 20 (%) > This value scales the threshold at which the OS increases the performance of the processor.
PerfIncreaseAbsoluteModifier > 1 (%) > This value offsets the threshold at which the OS increases the performance of the processor.
PerfDecreasePercentModifier > 30 (%) > This value scales the threshold at which the OS decreases the performance of the processor.
PerfDecreaseAbsoluteModifier > 1 (%) > This value offsets the threshold at which the OS decreases the performance of the processor.
PerfIncreaseTimeValue > 10000 (10ms) > This value influences the amount of time that may pass before the OS will increase performance. This time is also influenced by the processor’s transition latency.
PerfIncreaseMinimumTime > 150000 (150ms) > This value sets a minimum amount of time that must pass before any increase in performance will be considered.
PerfDecreaseTimeValue > 10000 (10ms) > This value influences the amount of time that may pass before the OS will decrease performance. This time is also influenced by the processor’s transition latency.
PerfDecreaseMinimumTime > 500000 (500ms) > This value sets a minimum amount of time that must pass before any decrease in performance will be considered.
PerfDegradeThrottleMinCapacity > 50 (%) > This value sets a minimum performance level that will be used for any reason other than a thermal condition.
PerfMaxC3Frequency > 50 (%) > This value is the threshold at which the OS will stop using stop-clock throttling and just use idle states; i.e., if the machine is using the Degrade policy and the battery is low, the OS will throttle the CPU, unless the machine is spending at least this amount of its time in the ACPI C3 state.  If the machine is spending at least this amount of time in C3, then no throttling will be done, unless there is a thermal condition.

C-State Control Registry Key
In order to better utilize the power savings typically offered by the C3 state, Microsoft® Windows® employs a more aggressive C3 entry algorithm than did Windows 2000. This more aggressive use of C3 has caused stability issues with a very small subset of laptop computers.  Additionally, there are some systems that may have known platform-level problems when attempting to use C-states.
To facilitate control of the use of C-states, Windows provides the following registry key.
NOTE: This registry key is statically adjustable; that is, it is read once during the processor driver initialization code.  Adjustments made to this value will not take place until the next system reboot.
NOTE: This key does not apply to C-states described using the ACPI 2.0 _CST object.
The C-state registry key is:
KEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Processor\CStateFlags

CStateFlags:REG_DWORD
Bit 0 >Not Used
Bit 1 >When set, C2 is disabled
Bit 2 >When set, C3 is disabled
Bit 3 >When set, enables Windows 2000 C3 behavior

22-03-2006, 20:56	#589
marcoland Senior Member Iscritto dal: Mar 2005 Città: Falconara Messaggi: 1162	Cosa ne sapete di queste impostazioni? Scaricabile da qui http://download.microsoft.com/downlo...%20Control.doc Parameters to P-state policy Several parameters to Windows processor performance state controls are configurable via registry keys. These keys are provided with the intent that OEMs and system designers may tune the performance of Windows processor power management features to best suit specific platform designs, and allow adjustment to help achieve maximum battery life and realize the best system performance. NOTE: These parameters are statically adjustable; that is, they are read once during the kernel initialization code. Adjustments made to these values will not take place until the next system reboot. The following registry keys are found in: KEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Throttle (I VALORI SONO QUELLI DEFAULT) PerfTimeDelta > Hardware Transition Latency > This value influences the frequency with which the OS will re-evaluate appropriate performance state in the idle loop. PerfCriticalTimeDelta > 300000 (300ms) > An application may use so much of the CPU’s time that the OS will never enter the idle loop. In order to make sure that we will increase the performance of the CPU in this situation, the processor power policy manager sets a timer that will interrupt the application. This value influences the time that must pass before the timer will fire. PerfIncreasePercentModifier > 20 (%) > This value scales the threshold at which the OS increases the performance of the processor. PerfIncreaseAbsoluteModifier > 1 (%) > This value offsets the threshold at which the OS increases the performance of the processor. PerfDecreasePercentModifier > 30 (%) > This value scales the threshold at which the OS decreases the performance of the processor. PerfDecreaseAbsoluteModifier > 1 (%) > This value offsets the threshold at which the OS decreases the performance of the processor. PerfIncreaseTimeValue > 10000 (10ms) > This value influences the amount of time that may pass before the OS will increase performance. This time is also influenced by the processor’s transition latency. PerfIncreaseMinimumTime > 150000 (150ms) > This value sets a minimum amount of time that must pass before any increase in performance will be considered. PerfDecreaseTimeValue > 10000 (10ms) > This value influences the amount of time that may pass before the OS will decrease performance. This time is also influenced by the processor’s transition latency. PerfDecreaseMinimumTime > 500000 (500ms) > This value sets a minimum amount of time that must pass before any decrease in performance will be considered. PerfDegradeThrottleMinCapacity > 50 (%) > This value sets a minimum performance level that will be used for any reason other than a thermal condition. PerfMaxC3Frequency > 50 (%) > This value is the threshold at which the OS will stop using stop-clock throttling and just use idle states; i.e., if the machine is using the Degrade policy and the battery is low, the OS will throttle the CPU, unless the machine is spending at least this amount of its time in the ACPI C3 state.  If the machine is spending at least this amount of time in C3, then no throttling will be done, unless there is a thermal condition. C-State Control Registry Key In order to better utilize the power savings typically offered by the C3 state, Microsoft® Windows® employs a more aggressive C3 entry algorithm than did Windows 2000. This more aggressive use of C3 has caused stability issues with a very small subset of laptop computers.  Additionally, there are some systems that may have known platform-level problems when attempting to use C-states. To facilitate control of the use of C-states, Windows provides the following registry key. NOTE: This registry key is statically adjustable; that is, it is read once during the processor driver initialization code.  Adjustments made to this value will not take place until the next system reboot. NOTE: This key does not apply to C-states described using the ACPI 2.0 _CST object. The C-state registry key is: KEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Processor\CStateFlags CStateFlags:REG_DWORD Bit 0 >Not Used Bit 1 >When set, C2 is disabled Bit 2 >When set, C3 is disabled Bit 3 >When set, enables Windows 2000 C3 behavior __________________ Jane-Mi hanno detto che il lavoro di polizia è pericoloso Frank-È vero. Per questo ho addosso una bella canna Jane-Non ha paura che possa esplodere? Frank-Ce l'ho spesso questo problema Jane-E come reagisce? Frank-Vado a chiudermi di corsa nel bagno. --- Avere la consapevolezza di ciò che si sa; conoscere d'ignorare quello che non si sa: ecco il vero sapere. Confucio Ultima modifica di marcoland : 22-03-2006 alle 21:06.