1 .TH "CPUPOWER-IDLE-SET" "1" "0.1" "" "cpupower Manual" 2 .SH "NAME" 3 .LP 4 cpupower\-idle\-set \- Utility to set cpu idle state specific kernel options 5 .SH "SYNTAX" 6 .LP 7 cpupower [ \-c cpulist ] idle\-set [\fIoptions\fP] 8 .SH "DESCRIPTION" 9 .LP 10 The cpupower idle\-set subcommand allows to set cpu idle, also called cpu 11 sleep state, specific options offered by the kernel. One example is disabling 12 sleep states. This can be handy for power vs performance tuning. 13 .SH "OPTIONS" 14 .LP 15 .TP 16 \fB\-d\fR \fB\-\-disable\fR <STATE_NO> 17 Disable a specific processor sleep state. 18 .TP 19 \fB\-e\fR \fB\-\-enable\fR <STATE_NO> 20 Enable a specific processor sleep state. 21 .TP 22 \fB\-D\fR \fB\-\-disable-by-latency\fR <LATENCY> 23 Disable all idle states with a equal or higher latency than <LATENCY>. 24 25 Enable all idle states with a latency lower than <LATENCY>. 26 .TP 27 \fB\-E\fR \fB\-\-enable-all\fR 28 Enable all idle states if not enabled already. 29 30 .SH "REMARKS" 31 .LP 32 Cpuidle Governors Policy on Disabling Sleep States 33 34 .RS 4 35 Depending on the used cpuidle governor, implementing the kernel policy 36 how to choose sleep states, subsequent sleep states on this core, might get 37 disabled as well. 38 39 There are two cpuidle governors ladder and menu. While the ladder 40 governor is always available, if CONFIG_CPU_IDLE is selected, the 41 menu governor additionally requires CONFIG_NO_HZ. 42 43 The behavior and the effect of the disable variable depends on the 44 implementation of a particular governor. In the ladder governor, for 45 example, it is not coherent, i.e. if one is disabling a light state, 46 then all deeper states are disabled as well. Likewise, if one enables a 47 deep state but a lighter state still is disabled, then this has no effect. 48 .RE 49 .LP 50 Disabling the Lightest Sleep State may not have any Affect 51 52 .RS 4 53 If criteria are not met to enter deeper sleep states and the lightest sleep 54 state is chosen when idle, the kernel may still enter this sleep state, 55 irrespective of whether it is disabled or not. This is also reflected in 56 the usage count of the disabled sleep state when using the cpupower idle-info 57 command. 58 .RE 59 .LP 60 Selecting specific CPU Cores 61 62 .RS 4 63 By default processor sleep states of all CPU cores are set. Please refer 64 to the cpupower(1) manpage in the \-\-cpu option section how to disable 65 C-states of specific cores. 66 .RE 67 .SH "FILES" 68 .nf 69 \fI/sys/devices/system/cpu/cpu*/cpuidle/state*\fP 70 \fI/sys/devices/system/cpu/cpuidle/*\fP 71 .fi 72 .SH "AUTHORS" 73 .nf 74 Thomas Renninger <trenn@suse.de> 75 .fi 76 .SH "SEE ALSO" 77 .LP 78 cpupower(1), cpupower\-monitor(1), cpupower\-info(1), cpupower\-set(1), 79 cpupower\-idle\-info(1)
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