cpud.1

控制CPU的linux程序cpud、cpuctl

.\" Copyright (c) 2005 Alf Schlichting [e-mail]
.\" Copyright (c) 2004 Laurence Tratt
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.Dd April 13, 2005
.Dt cpud 1
.Sh NAME
.Nm cpud
.Nd Automatically adjust system performance
.Sh SYNOPSIS
.Nm cpud
.Op Fl d
.Sh DESCRIPTION
.Nm
automatically adjusts the
.Xr sysctl 3
.Pa hw.setperf
value depending on current processor usage. This allows laptop users to conserve
battery life whilst the machine is idling, but to have good performance when
performing CPU-intensive tasks.
.Pp
After startup
.Nm
listens on its socket for connections telling it what scheme to load. After 
loading
.Nm
continuously monitors CPU utilization, mains power and battery life. 
If the processor is being heavily utilized it will
try to increase system performance to compensate. If the processor is idling,
it will decrease system performance. As battery life decreases, the maximum
speed the machine can reach is gradually reduced to maximize battery life.
If the battery reaches the low, or critical state, system performance is
reduced to, and maintained at, the minimum until a change in circumstances
is detected.
.Pp
Use 
.Xr cpuctl 1
to control the behaviour of
.Nm .
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl d
Turn on debugging.
.Nm
prints debugging output to stderr showing it altering system performance. In
debugging mode,
.Nm
does not daemonize itself.
.El
.Pp
.Sh FILES
.Bl -tag -width /var/run/apmdev -compact
.It Pa /var/run/apmdev
default Unix domain socket for
.Xr apmd 4
used to monitor mains connection and remaining battery life.
.El
.Bl -tag -width /var/run/cpudev -compact
.It Pa /var/run/cpudev
default Unix domain socket for
.Xr cpud 1
used for controlling the daemon.
.El
.Bl -tag -width /etc/cpud.conf -compact
.It Pa /etc/cpud.conf
default configuration file.
.El
.Pp
.Sh SEE ALSO
.Xr apm 4 ,
.Xr sysctl 3 ,
.Xr sysctl 8 .
.Sh HISTORY
The
.Nm
command is based on perfd by
.An Laurence Tratt Aq [e-mail] .