pepc-pstates - Man Page

-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.

1. './tests/data', in the directory of the running program
2. '$PEPC_DATA_PATH/tests/data'
3. '$HOME/.local/share/pepc/tests/data'
4. '/usr/local/share/pepc/tests/data'
5. '/usr/share/pepc/tests/data'

--force-color

Force coloring of the text output.

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').

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').

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).

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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min_freq - Minimum CPU frequency

pepc pstates info [--min-freq]

pepc pstates config [--min-freq=<value>]

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').

"/sys/devices/system/cpu/policy0/scaling_min_freq", '0' is replaced with desired CPU number.

This property has CPU scope.

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max_freq - Maximum CPU frequency

pepc pstates info [--max-freq]

pepc pstates config [--max-freq=<value>]

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').

"/sys/devices/system/cpu/policy0/scaling_max_freq", '0' is replaced with desired CPU number.

This property has CPU scope.

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min_freq_limit - Minimum supported CPU frequency

pepc pstates info [--min-freq-limit]

Minimum supported CPU frequency is the minimum CPU frequency supported by the OS.

"/sys/devices/system/cpu/policy0/cpuinfo_min_freq", '0' is replaced with desired CPU number.

This property has CPU scope.

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max_freq_limit - Maximum supported CPU frequency

pepc pstates info [--min-freq-limit]

Maximum supported CPU frequency is the maximum CPU frequency supported by the OS.

"/sys/devices/system/cpu/policy0/cpuinfo_max_freq", '0' is replaced with desired CPU number.

This property has CPU scope.

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base_freq - Base CPU frequency

pepc pstates info [--base-freq]

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.

"/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.

This property has CPU scope.

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min_freq_hw - Minimum CPU frequency

pepc pstates info [--min-freq-hw]

pepc pstates config [--min-freq-hw=<value>]

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').

MSR_HWP_REQUEST (0x774), bits 7:0.

This property has CPU scope.

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max_freq_hw - Maximum CPU frequency

pepc pstates info [--max-freq-hw]

pepc pstates config [--max-freq-hw=<value>]

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').

MSR_HWP_REQUEST (0x774), bits 15:8.

This property has CPU scope.

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bus_clock - Bus clock speed.

pepc pstates info [--bus-clock]

Bus clock refers to how quickly the system bus can move data from one computer component to the other.

MSR_FSB_FREQ (0xCD), bits 2:0. For platforms that don't support MSR_FSB_FREQ, 100.0MHz is used.

This property has package scope. With the following exception, Silvermonts and Airmonts have module scope.

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min_oper_freq - Minimum CPU operating frequency

pepc pstates info [--min-oper-freq]

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.

MSR_PLATFORM_INFO (0xCE), bits 55:48.

This property has CPU scope.

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max_eff_freq - Maximum CPU efficiency frequency

pepc pstates info [--max-eff-freq]

Maximum efficiency frequency is the most energy efficient CPU frequency. This frequency is also referred to as LFM (Low Frequency Mode) or Pn.

MSR_PLATFORM_INFO (0xCE), bits 47:40.

This property has CPU scope.

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turbo - Turbo

pepc pstates info [--turbo]

pepc pstates config [--turbo=<value>]

When turbo is enabled, the CPUs can automatically run at a frequency greater than base frequency.

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"

This property has global scope.

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max_turbo_freq - Maximum CPU turbo frequency

pepc pstates info [--max-eff-freq]

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.

MSR_TURBO_RATIO_LIMIT (0x1AD), bits 7:0.

This property has CPU scope.

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min_uncore_freq - Minimum uncore frequency

pepc pstates info [--min-uncore-freq]

pepc pstates config [--min-uncore-freq=<value>]

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').

"/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.

This property has die scope.

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max_uncore_freq - Maximum uncore frequency

pepc pstates info [--max-uncore-freq]

pepc pstates config [--max-uncore-freq=<value>]

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').

"/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.

This property has die scope.

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min_uncore_freq_limit - Minimum supported uncore frequency

pepc pstates info [--min-uncore-freq-limit]

Minimum supported uncore frequency is the lowest uncore frequency supported by the OS.

"/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.

This property has die scope.

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max_uncore_freq_limit - Maximum supported uncore frequency

pepc pstates info [--max-uncore-freq-limit]

Maximum supported uncore frequency is the highest uncore frequency supported by the OS.

"/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.

This property has die scope.

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hwp - Hardware power management

pepc pstates info [--hwp]

When hardware power management is enabled, CPUs can automatically scale their frequency without active OS involvement.

MSR_PM_ENABLE (0x770), bit 0.

This property has global scope.

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epp - Energy Performance Preference

pepc pstates info [--epp]

pepc pstates config [--epp=<value>]

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.

"/sys/devices/system/cpu/cpufreq/policy0/energy_performance_preference", '0' is replaced with desired CPU number.

This property has CPU scope.

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epp_hw - Energy Performance Preference

pepc pstates info [--epp-hw]

pepc pstates config [--epp-hw=<value>]

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.

MSR_HWP_REQUEST (0x774), bits 31:24.

This property has CPU scope.

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epb - Energy Performance Bias

pepc pstates info [--epb]

pepc pstates config [--epb=<value>]

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.

"/sys/devices/system/cpu/cpu0/power/energy_perf_bias", '0' is replaced with desired CPU number.

This property has CPU scope.

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epb_hw - Energy Performance Preference

pepc pstates info [--epb-hw]

pepc pstates config [--epb-hw=<value>]

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).

MSR_ENERGY_PERF_BIAS (0x1B0), bits 3:0.

This property has CPU scope. With the following exceptions, Silvermonts have core scope, Westmeres and Sandybridges have package scope.

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driver - CPU frequency driver

pepc pstates info [--driver]

CPU frequency driver enumerates and requests the P-states available on the platform.

"/sys/devices/system/cpu/cpufreq/policy0/scaling_driver", '0' is replaced with desired CPU number.

This property has global scope.

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intel_pstate_mode - Operation mode of 'intel_pstate' driver

pepc pstates info [--intel-pstate-mode]

pepc pstates config [--intel-pstate-mode=<value>]

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).

"/sys/devices/system/cpu/intel_pstate/status"

This property has global scope.

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governor - CPU frequency governor

pepc pstates info [--governor]

pepc pstates config [--governor=<value>]

CPU frequency governor decides which P-state to select on a CPU depending on CPU business and other factors.

"/sys/devices/system/cpu/cpufreq/policy0/scaling_governor", '0' is replaced with desired CPU number.

This property has CPU scope.

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governors - Available CPU frequency governors

pepc pstates info [--governors]

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.

"/sys/devices/system/cpu/cpufreq/policy0/scaling_available_governors", '0' is replaced with desired CPU number.)

This property has global scope.