diff options
author | Thomas Renninger <trenn@suse.de> | 2013-11-16 14:39:21 +0100 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-11-25 23:10:50 +0100 |
commit | 5094d271715a5bd0f7f4adb38d825ce6903eb6eb (patch) | |
tree | 2dd49051a9ef3958b49bf96ac97606a8bf82b44f /tools/power/cpupower/man/cpupower-idle-set.1 | |
parent | 6ce4eac1f600b34f2f7f58f9cd8f0503d79e42ae (diff) |
tools: cpupower: Add cpupower-idle-set(1) manpage
The cpupower idle-set subcommand was introduce recently.
This patch provides the missing manpage.
If cpupower is properly installed it will show up automatically
(similar to git), when invoking:
cpupower help idle-set
or
cpupower idle-set --help
Some parts have been taken over and adjusted from
git commit 62d6ae880e3e76098
documentation submitted by Carsten Emde.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'tools/power/cpupower/man/cpupower-idle-set.1')
-rw-r--r-- | tools/power/cpupower/man/cpupower-idle-set.1 | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/tools/power/cpupower/man/cpupower-idle-set.1 b/tools/power/cpupower/man/cpupower-idle-set.1 new file mode 100644 index 000000000000..6b1607272a5b --- /dev/null +++ b/tools/power/cpupower/man/cpupower-idle-set.1 @@ -0,0 +1,71 @@ +.TH "CPUPOWER-IDLE-SET" "1" "0.1" "" "cpupower Manual" +.SH "NAME" +.LP +cpupower idle\-set \- Utility to set cpu idle state specific kernel options +.SH "SYNTAX" +.LP +cpupower [ \-c cpulist ] idle\-info [\fIoptions\fP] +.SH "DESCRIPTION" +.LP +The cpupower idle\-set subcommand allows to set cpu idle, also called cpu +sleep state, specific options offered by the kernel. One example is disabling +sleep states. This can be handy for power vs performance tuning. +.SH "OPTIONS" +.LP +.TP +\fB\-d\fR \fB\-\-disable\fR +Disable a specific processor sleep state. +.TP +\fB\-e\fR \fB\-\-enable\fR +Enable a specific processor sleep state. + +.SH "REMARKS" +.LP +Cpuidle Governors Policy on Disabling Sleep States + +.RS 4 +Depending on the used cpuidle governor, implementing the kernel policy +how to choose sleep states, subsequent sleep states on this core, might get +disabled as well. + +There are two cpuidle governors ladder and menu. While the ladder +governor is always available, if CONFIG_CPU_IDLE is selected, the +menu governor additionally requires CONFIG_NO_HZ. + +The behavior and the effect of the disable variable depends on the +implementation of a particular governor. In the ladder governor, for +example, it is not coherent, i.e. if one is disabling a light state, +then all deeper states are disabled as well. Likewise, if one enables a +deep state but a lighter state still is disabled, then this has no effect. +.RE +.LP +Disabling the Lightest Sleep State may not have any Affect + +.RS 4 +If criteria are not met to enter deeper sleep states and the lightest sleep +state is chosen when idle, the kernel may still enter this sleep state, +irrespective of whether it is disabled or not. This is also reflected in +the usage count of the disabled sleep state when using the cpupower idle-info +command. +.RE +.LP +Selecting specific CPU Cores + +.RS 4 +By default processor sleep states of all CPU cores are set. Please refer +to the cpupower(1) manpage in the \-\-cpu option section how to disable +C-states of specific cores. +.RE +.SH "FILES" +.nf +\fI/sys/devices/system/cpu/cpu*/cpuidle/state*\fP +\fI/sys/devices/system/cpu/cpuidle/*\fP +.fi +.SH "AUTHORS" +.nf +Thomas Renninger <trenn@suse.de> +.fi +.SH "SEE ALSO" +.LP +cpupower(1), cpupower\-monitor(1), cpupower\-info(1), cpupower\-set(1), +cpupower\-idle\-info(1) |