cpupower-idle-set(1)

1CPUPOWER-IDLE-SET(1)            cpupower Manual           CPUPOWER-IDLE-SET(1)
2
3
4

NAME

6       cpupower  idle-set  -  Utility  to  set  cpu idle state specific kernel
7       options
8

SYNTAX

10       cpupower [ -c cpulist ] idle-info [options]
11

DESCRIPTION

13       The cpupower idle-set subcommand allows to set cpu  idle,  also  called
14       cpu sleep state, specific options offered by the kernel. One example is
15       disabling sleep states. This can be handy for power vs performance tun‐
16       ing.
17

OPTIONS

19       -d --disable <STATE_NO>
20              Disable a specific processor sleep state.
21
22       -e --enable <STATE_NO>
23              Enable a specific processor sleep state.
24
25       -D --disable-by-latency <LATENCY>
26              Disable  all  idle  states  with  a equal or higher latency than
27              <LATENCY>.
28
29              Enable all idle states with a latency lower than <LATENCY>.
30
31       -E --enable-all
32              Enable all idle states if not enabled already.
33
34

REMARKS

36       Cpuidle Governors Policy on Disabling Sleep States
37
38           Depending on the used  cpuidle governor,  implementing  the  kernel
39           policy  how to choose sleep states, subsequent sleep states on this
40           core, might get disabled as well.
41
42           There are two cpuidle governors ladder and menu. While  the  ladder
43           governor  is  always available, if CONFIG_CPU_IDLE is selected, the
44           menu governor additionally requires CONFIG_NO_HZ.
45
46           The behavior and the effect of the disable variable depends on  the
47           implementation  of  a  particular governor. In the ladder governor,
48           for example, it is not coherent, i.e. if one is disabling  a  light
49           state,  then  all  deeper states are disabled as well. Likewise, if
50           one enables a deep state but a lighter  state  still  is  disabled,
51           then this has no effect.
52
53       Disabling the Lightest Sleep State may not have any Affect
54
55           If criteria are not met to enter deeper sleep states and the light‐
56           est sleep state is chosen when idle, the  kernel  may  still  enter
57           this  sleep  state,  irrespective of whether it is disabled or not.
58           This is also reflected in the usage count  of  the  disabled  sleep
59           state when using the cpupower idle-info command.
60
61       Selecting specific CPU Cores
62
63           By  default processor sleep states of all CPU cores are set. Please
64           refer to the cpupower(1) manpage in the --cpu option section how to
65           disable C-states of specific cores.
66

FILES

68       /sys/devices/system/cpu/cpu*/cpuidle/state*
69       /sys/devices/system/cpu/cpuidle/*
70

AUTHORS

72       Thomas Renninger <trenn@suse.de>
73