Intel processors have model-specific registers (MSRs) containing measurements of how much time is spent in different C-states, and tools such as powermetrics (Mac), powertop and turbostat (Linux) can expose this information.Ī wakeup occurs when a core or package transitions from an idle state to the active state. This is a misleading term - the active state, C0, is also a C-state - but one that is nonetheless common. The fraction of time that a package or core spends in an idle C-state is called the C-state residency. if all cores are idle then the entire package can also become idle, which reduces power consumption even further.
The other thing to note about C-states is that they apply both to cores and the entire package - i.e. The important thing is that C0 is always the active state, and for the idle states a higher number always means less power consumption.
#INTEL POWER GADGET SUCKS ON WINDOWS MANUAL#
The exact relationship is confusing, and chapter 13 of the Intel optimization manual has more details. and many tools report C-states using the latter names. Intel maps these to processor-specific states such as C0, C1, C2, C6 and C7. Note: the ACPI standard specifies four states, C0, C1, C2 and C3. The deeper an idle state is, the less power it uses, but the longer it takes to wake up from. The other states have higher numbers and reflect increasing deeper idle states. C0 is the active/busy state, where instructions are being executed. These different states are called C-states. The first is the ability to switch frequently (thousands of times per second) between active and idle states, and there are actually several different kinds of idle states. Intel processors have aggressive power-saving features. It includes various components including the 元 cache, memory controller, and, for processors that have one, the integrated GPU.
These are part of the actual processor that you buy from Intel.
reducing) the power consumption caused by Firefox and Firefox OS. As a result, it is worth optimizing (i.e. Web browsers are popular applications and can be power-intensive, and therefore can significantly affect battery life.
#INTEL POWER GADGET SUCKS ON WINDOWS SOFTWARE#
That in turn depends on the software running on the device. In the context of computing, a fully-charged mobile device battery (as found in a laptop or smartphone) holds a certain amount of energy, and the speed at which that stored energy is depleted depends on the power consumption of the mobile device. Strictly speaking, such a computation gives the average power but this is often referred to as just the power when context makes it clear. by dividing an energy amount by a non-infinitesimal time period. In SI units, energy is measured in Joules, and power is measured in Watts, which is equivalent to Joules per second.Īlthough power is an instantaneous concept, in practice measurements of it are determined in a non-instantaneous fashion, i.e. It is equivalent to an amount of energy consumed per unit time. In physics, power is the rate of doing work. It serves as a starting point for anybody doing power profiling for the first time. This article covers important background information about power profiling, with an emphasis on Intel processors used in desktop and laptop machines.
0 kommentar(er)
