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32 .Nd "system power control utility"
49 utility monitors the system state and sets various power control options
51 It offers power-saving modes that can be
52 individually selected for operation on AC power or batteries.
53 .Bl -tag -width ".Ar hiadaptive"
55 Choose the highest performance values.
59 Choose the lowest performance values to get the most power savings.
63 Attempt to strike a balance by degrading performance when the system
64 appears idle and increasing it when the system is busy.
65 It offers a good balance between a small performance loss for greatly
66 increased power savings.
72 mode, but tuned for systems where performance and interactivity are
73 more important than power consumption.
74 It increases frequency faster, reduces frequency less aggressively, and
75 will maintain full frequency for longer.
87 recognizes these runtime options:
88 .Bl -tag -width ".Fl r Ar percent"
92 to use while on AC power.
96 to use while on battery power.
98 Specifies the CPU load percent level when adaptive
99 mode should begin to degrade performance to save power.
100 The default is 50% or lower.
102 Specifies the minimum frequency to throttle down to.
104 Specifies the maximum frequency to throttle up to.
108 to use normally when the AC line state is unknown.
110 Specifies a different polling interval (in milliseconds) for AC line state
111 and system idle levels.
112 The default is 250 ms.
114 Specifies an alternative file in which the process ID should be stored.
116 .Pa /var/run/powerd.pid .
118 Specifies the CPU load percent level where adaptive
119 mode should consider the CPU running and increase performance.
120 The default is 75% or higher.
122 Enforces method for AC line state refresh; by default, it is chosen
124 The set of valid methods is
131 Messages about power changes will be printed to stdout and
133 will operate in the foreground.
142 utility first appeared in
155 added features, and wrote this manual page.
159 utility should also power down idle disks and other components besides the CPU.
165 they may override each other.
170 should probably use the
172 interface instead of polling for AC line state.