All trademarks used are properties of their respective owners. This module might not be listed in the running modules but is still available. You will need to use whatever package manager yours system uses. Minimum time in microseconds that has to pass between two consecutive runs of governor computations default: If the value in this file is 1, the frequency boost mechanism is enabled. By “echoing” a new frequency into this. Remember you can see what modules are loaded with the lsmod command.

Uploader: Dorg
Date Added: 4 May 2006
File Size: 26.11 Mb
Operating Systems: Windows NT/2000/XP/2003/2003/7/8/10 MacOS 10/X
Downloads: 23828
Price: Free* [*Free Regsitration Required]

That directory contains a policyX subdirectory where X represents an integer number for every policy object maintained by the CPUFreq core. As a rule, each governor implements one, possibly parametrized, scaling algorithm.

That is, for example, the same register or set of registers is used to control the P-state of multiple CPUs at the same time and writing to it affects all of those CPUs simultaneously. The cpb knob is never present for any processors without the underlying hardware feature e.

By “echoing” a new frequency into this.

acpi-cpufreq: Add support for modern AMD CPUs

If that does for you then you don’t need to go through the parts of finding and loading the correct modules below. To do this the CPU must have the capability to switch the frequency very quickly.

Frequency fluctuations in some bursty workloads may be avoided this way at the cost of additional energy spent on maintaining the maximum CPU capacity. I believe in microseconds also.


Here are those CPUFreq governor benchmarks for those interested in squeezing slightly better performance out of your HEDT system by changing cpuferq aggressively or not the system is shifting power states to higher frequencies. All benchmarks were carried out in a fully-automated and reproducible environment using the Phoronix Test Suite.

Remember to put the cpufrsq of your CPU’s module you found above in here also so it loads on boot. Powersave governor – CPU runs at min frequency regardless of load. The second way to keep your settings on reboot is to install sysfsutils sudo apt-get install sysfsutils.

acpi-cpufreq: Add support for modern AMD CPUs []

In either case the name of the subdirectory containing the governor tunables is the name of the governor providing them. So when the CPU scales it will only ccpufreq to a max of and not When you installed your system there is a very good chance your CPU was detected by default and the module you need for for scaling is already running. Ondemand governor – sets the CPU frequency depending on the current usage.

That value can be used to estimate how the performance of the workload running on a CPU will change in response to frequency changes. When set to ‘0’ its defaultall processes are counted towards the ‘cpu utilization’ value. Every time the governor type changes all values get reset. Some BIOS’s may not have an option for either.

If that is the case check your BIOS’s manual for more information. List of Online CPUs that require software.


HowTo/CpuFrequencyScaling – Debian Wiki

Some CPU frequency scaling – capable processor switch between various. Reproducible results are important when running benchmarks. In that case, it only is necessary to restart the scaling governor so that it can take the new online CPU into account.

This would be best used in a battery powered environment. Current frequency of the CPU as determined by.

CPU frequency scaling

It does not mean that boosting is actually in use at the moment on any CPUs in the system. Make sure your kernel version is at least 2. If you have selected the “userspace” governor which allows you to.

To examine the impact of the frequency boost mechanism itself, it is useful to be able to run tests with and without boosting, ams without restarting the system in the meantime. It will also lower the temperature cpyfreq your processor s to keep your machine cooler. They are created by the CPUFreq core and their behavior generally does not depend on what scaling driver is in use and what scaling governor is attached to the given policy.