pepc-pstates - Man Page
Command 'pstates'
General options
- -h
Show a short help message and exit.
- -q
Be quiet.
- -d
Print debugging information.
- --version
Print version and exit.
- -H HOSTNAME, --host HOSTNAME
Name of the host to run the command on.
- -U USERNAME, --username USERNAME
Name of the user to use for logging into the remote host over SSH. The default user name is 'root'.
- -K PRIVKEY, --priv-key PRIVKEY
Path to the private SSH key that should be used for logging into the remote host. By default the key is automatically found from standard paths like '$HOME/.ssh'.
- -T TIMEOUT, --timeout TIMEOUT
SSH connection timeout in seconds, default is 8.
- -D DATASET, --dataset DATASET
This option is for debugging and testing purposes only, it defines the dataset that will be used to emulate a host for running the command on. This option is typically used when running 'pepc' from the source directory, which includes datasets for many different systems.
The argument can be the dataset path, 'all' to specify all available dataset or name in which case the following locations will be searched for.
- './tests/data', in the directory of the running program
- '$PEPC_DATA_PATH/tests/data'
- '$HOME/.local/share/pepc/tests/data'
- '/usr/local/share/pepc/tests/data'
- '/usr/share/pepc/tests/data'
- --force-color
Force coloring of the text output.
Subcommand 'info'
Get P-states information for specified CPUs. By default, prints all information for all CPUs.
- --cpus CPUS
List of CPUs to get information about. The list can include individual CPU numbers and CPU number ranges. For example,'1-4,7,8,10-12' would mean CPUs 1 to 4, CPUs 7, 8, and 10 to 12. Use the special keyword 'all' to specify all CPUs.
- --cores CORES
List of cores to get information about. The list can include individual core numbers and core number ranges. For example, '1-4,7,8,10-12' would mean cores 1 to 4, cores 7, 8, and 10 to 1. Use the special keyword 'all' to specify all cores. This option has to be accompanied by '--package' option, because core numbers are per-package.
- --packages PACKAGES
List of packages to get information about. The list can include individual package numbers and package number ranges. For example, '0,2-4' would mean package 0 and packages 2 to 4. Use the special keyword 'all' to specify all packages.
- --core-siblings CORE_SIBLINGS
List of core sibling indices to get information about. The list can include individual core sibling indices or index ranges. For example, core x includes CPUs 3 and 4, '0' would mean CPU 3 and '1' would mean CPU 4. This option can only be used to reference online CPUs, because Linux does not provide topology information for offline CPUs. In the previous example if CPU 3 was offline, then '0' would mean CPU 4.
- --yaml
Print information in YAML format.
- --override-cpu-model
This option is for debugging and testing purposes only. Provide the CPU model number which the tool treats the target system CPU as. For example, use 0x8F to treat the target system as Sapphire Rapids Xeon.
- --min-freq
Get minimum CPU frequency (details in 'min_freq').
- --max-freq
Get maximum CPU frequency (details in 'max_freq').
- --min-freq-limit
Get minimum supported CPU frequency (details in 'min_freq_limit').
- --max-freq-limit
Get maximum supported CPU frequency (details in 'max_freq_limit').
- --base-freq
Get base CPU frequency (details in 'base_freq').
- --min-freq-hw
Get minimum CPU frequency (OS bypass) (details in 'min_freq_hw').
- --max-freq-hw
Get maximum CPU frequency (OS bypass) (details in 'max_freq_hw').
- --bus-clock
Get bus clock speed (details in 'bus_clock').
- --min-oper-freq
Get minimum CPU operating frequency (details in 'min_oper_freq').
- --max-eff-freq
Get maximum CPU efficiency frequency (details in 'max_eff_freq').
- --turbo
Get current setting for turbo (details in 'turbo').
- --max-turbo-freq
Get maximum CPU turbo frequency (details in 'max_turbo_freq').
- --min-uncore-freq
Get minimum uncore frequency (details in 'min_uncore_freq').
- --max-uncore-freq
Get maximum uncore frequency (details in 'max_uncore_freq').
- --min-uncore-freq-limit
Get minimum supported uncore frequency (details in 'min_uncore_freq_limit').
- --max-uncore-freq-limit
Get maximum supported uncore frequency (details in 'max_uncore_freq_limit').
- --hwp
Get current setting for hardware power management (details in 'hwp').
- --epp
Get EPP via sysfs (details in 'epp').
- --epp-hw
Get EPP via MSR (details in 'epp_hw').
- --epb
Get EPB via sysfs (details in 'epb').
- --epb-hw
Get EPB via MSR (details in 'epb_hw').
- --driver
Get CPU frequency driver (details in 'driver').
- --intel-pstate-mode
Get operation mode of 'intel_pstate' driver (details in 'intel_pstate_mode').
- --governor
Get CPU frequency governor (details in 'governor').
- --governors
Get list of available CPU frequency governors (details in 'governors').
Subcommand 'config'
Configure P-states on specified CPUs. All options can be used without a parameter, in which case the currently configured value(s) will be printed.
- --cpus CPUS
List of CPUs to configure P-States on. The list can include individual CPU numbers and CPU number ranges. For example,'1-4,7,8,10-12' would mean CPUs 1 to 4, CPUs 7, 8, and 10 to 12. Use the special keyword 'all' to specify all CPUs.
- --cores CORES
List of cores to configure P-States on. The list can include individual core numbers and core number ranges. For example, '1-4,7,8,10-12' would mean cores 1 to 4, cores 7, 8, and 10 to 12. Use the special keyword 'all' to specify all cores. This option has to be accompanied by '--package' option, because core numbers are per-package.
- --packages PACKAGES
List of packages to configure P-States on. The list can include individual package numbers and package number ranges. For example, '0,2-4' would mean package 0 and packages 2 to 4. Use the special keyword 'all' to specify all packages.
- --core-siblings CORE_SIBLINGS
List of core sibling indices to configure P-States on. The list can include individual core sibling indices or index ranges. For example, core x includes CPUs 3 and 4, '0' would mean CPU 3 and '1' would mean CPU 4. This option can only be used to reference online CPUs, because Linux does not provide topology information for offline CPUs. In the previous example if CPU 3 was offline, then '0' would mean CPU 4.
- --override-cpu-model
This option is for debugging and testing purposes only. Provide the CPU model number which the tool treats the target system CPU as. For example, use 0x8F to treat the target system as Sapphire Rapids Xeon.
- --min-freq [MIN_FREQ]
Set minimum CPU frequency (details in 'min_freq').
- --max-freq [MAX_FREQ]
Set maximum CPU frequency (details in 'max_freq').
- --min-freq-hw [MIN_FREQ_HW]
Set minimum CPU frequency (OS bypass) (details in 'min_freq_limit').
- --max-freq-hw [MAX_FREQ_HW]
Set maximum CPU frequency (OS bypass) (details in 'max_freq_limit').
- --turbo [TURBO]
Enable or disable turbo (details in 'turbo').
- --min-uncore-freq [MIN_UNCORE_FREQ]
Set minimum uncore frequency (details in 'min_uncore_freq').
- --max-uncore-freq [MAX_UNCORE_FREQ]
Set maximum uncore frequency (details in 'max_uncore_freq').
- --epp [EPP]
Set EPP via sysfs (details in 'epp').
- --epp-hw [EPP_HW]
Set EPP via MSR (details in 'epp_hw').
- --epb [EPB]
Set EPB via sysfs (details in 'epb').
- --epb-hw [EPB_HW]
Set EPB via MSR (details in 'epb_hw').
- --intel-pstate-mode [INTEL_PSTATE_MODE]
Set operation mode of 'intel_pstate' driver (details in 'intel_pstate_mode').
- --governor [GOVERNOR]
Set CPU frequency governor (details in 'governor').
Subcommand 'save'
Save all the modifiable P-state settings into a file. This file can later be used for restoring P-state settings with the 'pepc pstates restore' command.
- --cpus CPUS
List of CPUs to save P-state information about. The list can include individual CPU numbers and CPU number ranges. For example,'1-4,7,8,10-12' would mean CPUs 1 to 4, CPUs 7, 8, and 10 to 12. Use the special keyword 'all' to specify all CPUs.
- --cores CORES
List of cores to save P-state information about. The list can include individual core numbers and core number ranges. For example, '1-4,7,8,10-12' would mean cores 1 to 4, cores 7, 8, and 10 to 12. Use the special keyword 'all' to specify all cores. This option has to be accompanied by '--package' option, because core numbers are per-package.
- --packages PACKAGES
List of packages to save P-state information about. The list can include individual package numbers and package number ranges. For example, '0,2-4' would mean package 0 and packages 2 to 4. Use the special keyword 'all' to specify all packages.
- --core-siblings CORE_SIBLINGS
List of core sibling indices to save P-state information about. The list can include individual core sibling indices or index ranges. For example, core x includes CPUs 3 and 4, '0' would mean CPU 3 and '1' would mean CPU 4. This option can only be used to reference online CPUs, because Linux does not provide topology information for offline CPUs. In the previous example if CPU 3 was offline, then '0' would mean CPU 4.
- -o OUTFILE, --outfile OUTFILE
Name of the file to save the settings to (printed to standard output by default).
Subcommand 'restore'
Restore P-state settings from a file previously created with the 'pepc pstates save' command.
- -f INFILE, --from INFILE
Name of the file from which to restore the settings from, use "-" to read from the standard output.
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Properties
min_freq
min_freq - Minimum CPU frequency
Synopsis
pepc pstates info [--min-freq]
pepc pstates config [--min-freq=<value>]
Description
Minimum CPU frequency is the lowest frequency the OS configured the CPU to run at, via sysfs knobs.
The default unit is "Hz", but "kHz", "MHz", and "GHz" can also be used (for example "900MHz").
The following special values are supported:
- "min"
Minimum CPU frequency supported (see 'min_freq_limit').
- "max"
Maximum CPU frequency supported (see 'max_freq_limit').
- "base", "hfm", "P1"
Base CPU frequency (see 'base_freq').
- "eff", "lfm", "Pn"
Maximum CPU efficiency frequency (see 'max_eff_freq').
- "Pm"
Minimum CPU operating frequency (see 'min_oper_freq').
Source
"/sys/devices/system/cpu/policy0/scaling_min_freq", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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max_freq
max_freq - Maximum CPU frequency
Synopsis
pepc pstates info [--max-freq]
pepc pstates config [--max-freq=<value>]
Description
Maximum CPU frequency is the lowest frequency the OS configured the CPU to run at, via sysfs knobs.
The default unit is "Hz", but "kHz", "MHz", and "GHz" can also be used (for example "900MHz").
The following special values are supported:
- "min"
Minimum CPU frequency supported (see 'min_freq_limit').
- "max"
Maximum CPU frequency supported (see 'max_freq_limit').
- "base", "hfm", "P1"
Base CPU frequency (see 'base_freq').
- "eff", "lfm", "Pn"
Maximum CPU efficiency frequency (see 'max_eff_freq').
- "Pm"
Minimum CPU operating frequency (see 'min_oper_freq').
Source
"/sys/devices/system/cpu/policy0/scaling_max_freq", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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min_freq_limit
min_freq_limit - Minimum supported CPU frequency
Synopsis
pepc pstates info [--min-freq-limit]
Description
Minimum supported CPU frequency is the minimum CPU frequency supported by the OS.
Source
"/sys/devices/system/cpu/policy0/cpuinfo_min_freq", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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max_freq_limit
max_freq_limit - Maximum supported CPU frequency
Synopsis
pepc pstates info [--min-freq-limit]
Description
Maximum supported CPU frequency is the maximum CPU frequency supported by the OS.
Source
"/sys/devices/system/cpu/policy0/cpuinfo_max_freq", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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base_freq
base_freq - Base CPU frequency
Synopsis
pepc pstates info [--base-freq]
Description
Base CPU frequency is the highest sustainable CPU frequency. This frequency is also referred to as "guaranteed frequency", HFM (High Frequency Mode), or P1.
The base frequency is acquired from a sysfs file or from an MSR register, if the sysfs file does not exist.
Source
"/sys/devices/system/cpu/policy0/base_frequency", '0' is replaced with desired CPU number.
If the sysfs path does not exists, falls back to MSR_PLATFORM_INFO (0xCE), bits 15:8.
Scope
This property has CPU scope.
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min_freq_hw
min_freq_hw - Minimum CPU frequency
Synopsis
pepc pstates info [--min-freq-hw]
pepc pstates config [--min-freq-hw=<value>]
Description
Minimum frequency the CPU is configured to run at. This value is read directly from the MSR, bypassing the OS.
The default unit is "Hz", but "kHz", "MHz", and "GHz" can also be used (for example "900MHz").
The following special values are supported:
- "min"
Minimum CPU frequency supported (see 'min_freq_limit').
- "max"
Maximum CPU frequency supported (see 'max_freq_limit').
- "base", "hfm", "P1"
Base CPU frequency (see 'base_freq').
- "eff", "lfm", "Pn"
Maximum CPU efficiency frequency (see 'max_eff_freq').
- "Pm"
Minimum CPU operating frequency (see 'min_oper_freq').
Source
MSR_HWP_REQUEST (0x774), bits 7:0.
Scope
This property has CPU scope.
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max_freq_hw
max_freq_hw - Maximum CPU frequency
Synopsis
pepc pstates info [--max-freq-hw]
pepc pstates config [--max-freq-hw=<value>]
Description
Maximum frequency the CPU is configured to run at. This value is read directly from the MSR, bypassing the OS.
The default unit is "Hz", but "kHz", "MHz", and "GHz" can also be used (for example "900MHz").
The following special values are supported:
- "min"
Minimum CPU frequency supported (see 'min_freq_limit').
- "max"
Maximum CPU frequency supported (see 'max_freq_limit').
- "base", "hfm", "P1"
Base CPU frequency (see 'base_freq').
- "eff", "lfm", "Pn"
Maximum CPU efficiency frequency (see 'max_eff_freq').
- "Pm"
Minimum CPU operating frequency (see 'min_oper_freq').
Source
MSR_HWP_REQUEST (0x774), bits 15:8.
Scope
This property has CPU scope.
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bus_clock
bus_clock - Bus clock speed.
Synopsis
pepc pstates info [--bus-clock]
Description
Bus clock refers to how quickly the system bus can move data from one computer component to the other.
Source
MSR_FSB_FREQ (0xCD), bits 2:0. For platforms that don't support MSR_FSB_FREQ, 100.0MHz is used.
Scope
This property has package scope. With the following exception, Silvermonts and Airmonts have module scope.
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min_oper_freq
min_oper_freq - Minimum CPU operating frequency
Synopsis
pepc pstates info [--min-oper-freq]
Description
Minimum operating frequency is the lowest possible frequency the CPU can operate at. Depending on the CPU model, this frequency may or may not be directly available to the OS, but the platform may use it in certain situations (e.g., in some C-states). This frequency is also referred to as Pm.
Source
MSR_PLATFORM_INFO (0xCE), bits 55:48.
Scope
This property has CPU scope.
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max_eff_freq
max_eff_freq - Maximum CPU efficiency frequency
Synopsis
pepc pstates info [--max-eff-freq]
Description
Maximum efficiency frequency is the most energy efficient CPU frequency. This frequency is also referred to as LFM (Low Frequency Mode) or Pn.
Source
MSR_PLATFORM_INFO (0xCE), bits 47:40.
Scope
This property has CPU scope.
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turbo
turbo - Turbo
Synopsis
pepc pstates info [--turbo]
pepc pstates config [--turbo=<value>]
Description
When turbo is enabled, the CPUs can automatically run at a frequency greater than base frequency.
Source
Location of the turbo knob in sysfs depends on the CPU frequency driver.
intel_pstate - "/sys/devices/system/cpu/intel_pstate/no_turbo"
acpi-cpufreq - "/sys/devices/system/cpu/cpufreq/boost"
Scope
This property has global scope.
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max_turbo_freq
max_turbo_freq - Maximum CPU turbo frequency
Synopsis
pepc pstates info [--max-eff-freq]
Description
Maximum 1-core turbo frequency is the highest frequency a single CPU can operate at. This frequency is also referred to as max. 1-core turbo and P01.
Source
MSR_TURBO_RATIO_LIMIT (0x1AD), bits 7:0.
Scope
This property has CPU scope.
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min_uncore_freq
min_uncore_freq - Minimum uncore frequency
Synopsis
pepc pstates info [--min-uncore-freq]
pepc pstates config [--min-uncore-freq=<value>]
Description
Minimum CPU frequency is the lowest frequency the OS configured the CPU to run at, via sysfs knobs.
The default unit is "Hz", but "kHz", "MHz", and "GHz" can also be used (for example "900MHz").
The following special values are supported:
- "min"
Minimum CPU frequency supported (see 'min_freq_limit').
- "max"
Maximum CPU frequency supported (see 'max_freq_limit').
Source
"/sys/devices/system/cpu/intel_uncore_frequency/package_00_die_01/min_freq_khz", '00' is replaced with desired package number and '01' with desired die number.
Scope
This property has die scope.
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max_uncore_freq
max_uncore_freq - Maximum uncore frequency
Synopsis
pepc pstates info [--max-uncore-freq]
pepc pstates config [--max-uncore-freq=<value>]
Description
Maximum CPU frequency is the highest frequency the OS configured the CPU to run at, via sysfs knobs.
The default unit is "Hz", but "kHz", "MHz", and "GHz" can also be used (for example "900MHz").
The following special values are supported:
- "min"
Minimum CPU frequency supported (see 'min_freq_limit').
- "max"
Maximum CPU frequency supported (see 'max_freq_limit').
Source
"/sys/devices/system/cpu/intel_uncore_frequency/package_00_die_01/max_freq_khz", '00' is replaced with desired package number and '01' with desired die number.
Scope
This property has die scope.
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min_uncore_freq_limit
min_uncore_freq_limit - Minimum supported uncore frequency
Synopsis
pepc pstates info [--min-uncore-freq-limit]
Description
Minimum supported uncore frequency is the lowest uncore frequency supported by the OS.
Source
"/sys/devices/system/cpu/intel_uncore_frequency/package_00_die_01/initial_min_freq_khz", '00' is replaced with desired package number and '01' with desired die number.
Scope
This property has die scope.
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max_uncore_freq_limit
max_uncore_freq_limit - Maximum supported uncore frequency
Synopsis
pepc pstates info [--max-uncore-freq-limit]
Description
Maximum supported uncore frequency is the highest uncore frequency supported by the OS.
Source
"/sys/devices/system/cpu/intel_uncore_frequency/package_00_die_01/initial_max_freq_khz", '00' is replaced with desired package number and '01' with desired die number.
Scope
This property has die scope.
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hwp
hwp - Hardware power management
Synopsis
pepc pstates info [--hwp]
Description
When hardware power management is enabled, CPUs can automatically scale their frequency without active OS involvement.
Source
MSR_PM_ENABLE (0x770), bit 0.
Scope
This property has global scope.
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epp
epp - Energy Performance Preference
Synopsis
pepc pstates info [--epp]
pepc pstates config [--epp=<value>]
Description
Energy Performance Preference is a hint to the CPU on energy efficiency vs performance. EPP value is a number in range of 0-255 (maximum energy efficiency to maximum performance), or a policy name.
Source
"/sys/devices/system/cpu/cpufreq/policy0/energy_performance_preference", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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epp_hw
epp_hw - Energy Performance Preference
Synopsis
pepc pstates info [--epp-hw]
pepc pstates config [--epp-hw=<value>]
Description
Energy Performance Preference is a hint to the CPU on energy efficiency vs performance. EPP value is a number in range of 0-255 (maximum energy efficiency to maximum performance).
When package control is enabled the value is read from MSR_HWP_REQUEST_PKG 0x772, but when written package control is disabled and value is written to MSR_HWP_REQUEST 0x774, both require the 'msr' Linux kernel driver.
Source
MSR_HWP_REQUEST (0x774), bits 31:24.
Scope
This property has CPU scope.
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epb
epb - Energy Performance Bias
Synopsis
pepc pstates info [--epb]
pepc pstates config [--epb=<value>]
Description
Energy Performance Bias is a hint to the CPU on energy efficiency vs performance. EBP value is a number in range of 0-15 (maximum performance to maximum energy efficiency), or a policy name.
Source
"/sys/devices/system/cpu/cpu0/power/energy_perf_bias", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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epb_hw
epb_hw - Energy Performance Preference
Synopsis
pepc pstates info [--epb-hw]
pepc pstates config [--epb-hw=<value>]
Description
Energy Performance Bias is a hint to the CPU on energy efficiency vs performance. EBP value is a number in range of 0-15 (maximum performance to maximum energy efficiency).
Source
MSR_ENERGY_PERF_BIAS (0x1B0), bits 3:0.
Scope
This property has CPU scope. With the following exceptions, Silvermonts have core scope, Westmeres and Sandybridges have package scope.
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driver
driver - CPU frequency driver
Synopsis
pepc pstates info [--driver]
Description
CPU frequency driver enumerates and requests the P-states available on the platform.
Source
"/sys/devices/system/cpu/cpufreq/policy0/scaling_driver", '0' is replaced with desired CPU number.
Scope
This property has global scope.
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intel_pstate_mode
intel_pstate_mode - Operation mode of 'intel_pstate' driver
Synopsis
pepc pstates info [--intel-pstate-mode]
pepc pstates config [--intel-pstate-mode=<value>]
Description
The 'intel_pstate' driver has 3 operation modes: 'active', 'passive' and 'off'. The main difference between the active and passive mode is in which frequency governors are used - the generic Linux governors (passive mode) or the custom, built-in 'intel_pstate' driver governors (active mode).
Source
"/sys/devices/system/cpu/intel_pstate/status"
Scope
This property has global scope.
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governor
governor - CPU frequency governor
Synopsis
pepc pstates info [--governor]
pepc pstates config [--governor=<value>]
Description
CPU frequency governor decides which P-state to select on a CPU depending on CPU business and other factors.
Source
"/sys/devices/system/cpu/cpufreq/policy0/scaling_governor", '0' is replaced with desired CPU number.
Scope
This property has CPU scope.
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governors
governors - Available CPU frequency governors
Synopsis
pepc pstates info [--governors]
Description
CPU frequency governors decide which P-state to select on a CPU depending on CPU business and other factors. Different governors implement different selection policy.
Source
"/sys/devices/system/cpu/cpufreq/policy0/scaling_available_governors", '0' is replaced with desired CPU number.)
Scope
This property has global scope.