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32 .Nd "system power control utility"
45 utility monitors the system state and sets various power control options
47 It offers three modes (max, min, and adaptive) that can be
48 individually selected while on AC power or batteries.
50 Maximum mode chooses the highest performance values.
51 Minimum mode selects the lowest performance values to get the most power
53 Adaptive mode attempts to strike a balance by degrading performance when
54 the system appears idle and increasing it when the system is busy.
55 It offers a good balance between a small performance loss for greatly
56 increased power savings.
62 utility recognizes the following runtime options:
63 .Bl -tag -width ".Fl r Ar percent"
67 to use while on AC power.
71 to use while on battery power.
73 Specifies the CPU idle percent level when
75 mode should begin to degrade performance to save power.
76 The default is 90% or higher.
80 to use normally when the AC line state is unknown.
82 Specifies a different polling interval (in milliseconds) for AC line state
83 and system idle levels.
84 The default is 500 ms.
86 Specifies the CPU idle percent level where
88 mode should consider the CPU running and increase performance.
89 The default is 65% or lower.
92 Messages about power changes will be printed to stdout and
94 will operate in the foreground.
103 utility first appeared in
116 added features, and wrote this manual page.
120 utility should also power down idle disks and other components besides the CPU.
126 they may override each other.
131 should probably use the
133 interface instead of polling for AC line state.