openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity
linux/tools/power/cpupower/man/cpupower-frequency-info.1

78 lines
2.3 KiB
Groff
Raw Normal View History

cpupower: Unify cpupower-frequency-* manpages cpupower-frequency-* manpages slightly differed from the others. - Use uppercase letters in the title - Show cpupower Manual in the header - Remove Mattia from left down corner of the manpage, he is already listed as author - Remove --help, prints this message -> not needed Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2011-12-16 22:35:52 +08:00
.TH "CPUPOWER\-FREQUENCY\-INFO" "1" "0.1" "" "cpupower Manual"
cpupowerutils - cpufrequtils extended with quite some features CPU power consumption vs performance tuning is no longer limited to CPU frequency switching anymore: deep sleep states, traditional dynamic frequency scaling and hidden turbo/boost frequencies are tied close together and depend on each other. The first two exist on different architectures like PPC, Itanium and ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will only run most efficiently if CPU and GPU has proper power management in place. Users and Developers want to have *one* tool to get an overview what their system supports and to monitor and debug CPU power management in detail. The tool should compile and work on as many architectures as possible. Once this tool stabilizes a bit, it is intended to replace the Intel-specific tools in tools/power/x86 Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2011-03-30 22:30:11 +08:00
.SH "NAME"
.LP
Fix cpupower manpages "NAME" section The token before "-" should be the program name, no spaces allowed. See man(7) and lexgrog(1). Signed-off-by: Mattia Dongili <malattia@linux.it> Signed-off-by: Thomas Renninger <trenn@suse.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-04-28 21:24:38 +08:00
cpupower\-frequency\-info \- Utility to retrieve cpufreq kernel information
cpupowerutils - cpufrequtils extended with quite some features CPU power consumption vs performance tuning is no longer limited to CPU frequency switching anymore: deep sleep states, traditional dynamic frequency scaling and hidden turbo/boost frequencies are tied close together and depend on each other. The first two exist on different architectures like PPC, Itanium and ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will only run most efficiently if CPU and GPU has proper power management in place. Users and Developers want to have *one* tool to get an overview what their system supports and to monitor and debug CPU power management in detail. The tool should compile and work on as many architectures as possible. Once this tool stabilizes a bit, it is intended to replace the Intel-specific tools in tools/power/x86 Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2011-03-30 22:30:11 +08:00
.SH "SYNTAX"
.LP
cpupower: use man(1) when calling "cpupower help subcommand" Instead of printing something non-formatted to stdout, call man(1) to show the man page for the proper subcommand. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2011-08-07 00:11:43 +08:00
cpupower [ \-c cpulist ] frequency\-info [\fIoptions\fP]
cpupowerutils - cpufrequtils extended with quite some features CPU power consumption vs performance tuning is no longer limited to CPU frequency switching anymore: deep sleep states, traditional dynamic frequency scaling and hidden turbo/boost frequencies are tied close together and depend on each other. The first two exist on different architectures like PPC, Itanium and ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will only run most efficiently if CPU and GPU has proper power management in place. Users and Developers want to have *one* tool to get an overview what their system supports and to monitor and debug CPU power management in detail. The tool should compile and work on as many architectures as possible. Once this tool stabilizes a bit, it is intended to replace the Intel-specific tools in tools/power/x86 Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2011-03-30 22:30:11 +08:00
.SH "DESCRIPTION"
.LP
A small tool which prints out cpufreq information helpful to developers and interested users.
.SH "OPTIONS"
.LP
.TP
\fB\-e\fR \fB\-\-debug\fR
Prints out debug information.
.TP
\fB\-f\fR \fB\-\-freq\fR
Get frequency the CPU currently runs at, according to the cpufreq core.
.TP
\fB\-w\fR \fB\-\-hwfreq\fR
Get frequency the CPU currently runs at, by reading it from hardware (only available to root).
.TP
\fB\-l\fR \fB\-\-hwlimits\fR
Determine the minimum and maximum CPU frequency allowed.
.TP
\fB\-d\fR \fB\-\-driver\fR
Determines the used cpufreq kernel driver.
.TP
\fB\-p\fR \fB\-\-policy\fR
Gets the currently used cpufreq policy.
.TP
\fB\-g\fR \fB\-\-governors\fR
Determines available cpufreq governors.
.TP
\fB\-a\fR \fB\-\-related\-cpus\fR
Determines which CPUs run at the same hardware frequency.
.TP
\fB\-a\fR \fB\-\-affected\-cpus\fR
Determines which CPUs need to have their frequency coordinated by software.
.TP
\fB\-s\fR \fB\-\-stats\fR
Shows cpufreq statistics if available.
.TP
\fB\-y\fR \fB\-\-latency\fR
Determines the maximum latency on CPU frequency changes.
.TP
\fB\-o\fR \fB\-\-proc\fR
Prints out information like provided by the /proc/cpufreq interface in 2.4. and early 2.6. kernels.
.TP
\fB\-m\fR \fB\-\-human\fR
human\-readable output for the \-f, \-w, \-s and \-y parameters.
.TP
PM / tools: cpupower: add option to display values without round offs The command "cpupower frequency-info" can be used when using cpupower to monitor and test processor behaviour to determine if the processor is behaving as expected. This data can be compared to the output of /proc/cpuinfo or the output of /sys/devices/system/cpu/cpuX/cpufreq/scaling_available_frequencies to determine if the cpu is in an expected state. When doing this I noticed comparison test failures due to the way the data is displayed in cpupower. For example, [root@intel-s3e37-02 cpupower]# cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 2262000 2261000 2128000 1995000 1862000 1729000 1596000 1463000 1330000 1197000 1064000 compared to [root@intel-s3e37-02 cpupower]# cpupower frequency-info analyzing CPU 0: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 10.0 us. hardware limits: 1.06 GHz - 2.26 GHz available frequency steps: 2.26 GHz, 2.26 GHz, 2.13 GHz, 2.00 GHz, 1.86 GHz, 1.73 GHz, 1.60 GHz, 1.46 GHz, 1.33 GHz, 1.20 GHz, 1.06 GHz available cpufreq governors: conservative, userspace, powersave, ondemand, performance current policy: frequency should be within 1.06 GHz and 2.26 GHz. The governor "performance" may decide which speed to use within this range. current CPU frequency is 2.26 GHz (asserted by call to hardware). boost state support: Supported: yes Active: yes shows very different values for the available frequency steps. The cpupower output rounds off values at 2 decimal points and this causes problems with test scripts. For example, with the data above, 1.064 is 1.06 1.197 is 1.20 1.596 is 1.60 1.995 is 2.00 2.128 is 2.13 and most confusingly, 2.261 is 2.26 2.262 is 2.26 Truncating these values serves no real purpose other than making the output pretty. Since the default has been to round off these values I am adding a -n/--no-rounding option to the cpupower utility that will display the data without rounding off the still significant digits. After patch, analyzing CPU 0: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 10.000 us. hardware limits: 1.064000 GHz - 2.262000 GHz available frequency steps: 2.262000 GHz, 2.261000 GHz, 2.128000 GHz, 1.995000 GHz, 1.862000 GHz, 1.729000 GHz, 1.596000 GHz, 1.463000 GHz, 1.330000 GHz, 1.197000 GHz, 1.064000 GHz available cpufreq governors: conservative, userspace, powersave, ondemand, performance current policy: frequency should be within 1.064000 GHz and 2.262000 GHz. The governor "performance" may decide which speed to use within this range. current CPU frequency is 2.262000 GHz (asserted by call to hardware). boost state support: Supported: yes Active: yes Acked-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Prarit Bhargava <prarit@redhat.com> [rjw: Subject] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-04-24 22:32:07 +08:00
\fB\-n\fR \fB\-\-no-rounding\fR
Output frequencies and latencies without rounding off values.
.TP
cpupowerutils - cpufrequtils extended with quite some features CPU power consumption vs performance tuning is no longer limited to CPU frequency switching anymore: deep sleep states, traditional dynamic frequency scaling and hidden turbo/boost frequencies are tied close together and depend on each other. The first two exist on different architectures like PPC, Itanium and ARM, the latter (so far) only on X86. On X86 the APU (CPU+GPU) will only run most efficiently if CPU and GPU has proper power management in place. Users and Developers want to have *one* tool to get an overview what their system supports and to monitor and debug CPU power management in detail. The tool should compile and work on as many architectures as possible. Once this tool stabilizes a bit, it is intended to replace the Intel-specific tools in tools/power/x86 Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2011-03-30 22:30:11 +08:00
.SH "REMARKS"
.LP
By default only values of core zero are displayed. How to display settings of
other cores is described in the cpupower(1) manpage in the \-\-cpu option section.
.LP
You can't specify more than one of the output specific options \-o \-e \-a \-g \-p \-d \-l \-w \-f \-y.
.LP
You also can't specify the \-o option combined with the \-c option.
.SH "FILES"
.nf
\fI/sys/devices/system/cpu/cpu*/cpufreq/\fP
\fI/proc/cpufreq\fP (deprecated)
\fI/proc/sys/cpu/\fP (deprecated)
.fi
.SH "AUTHORS"
.nf
Dominik Brodowski <linux@brodo.de> \- author
Mattia Dongili<malattia@gmail.com> \- first autolibtoolization
.fi
.SH "SEE ALSO"
.LP
cpupower\-frequency\-set(1), cpupower(1)