.\" Copyright 2017 IBM Corp.
.\" s390-tools is free software; you can redistribute it and/or modify
.\" it under the terms of the MIT license. See LICENSE for details.
.\"
.TH CPUPLUGD 8 "May 2011" "s390-tools"
.
.SH NAME
cpuplugd \- Linux on System z CPU and memory hotplug daemon
.
.SH SYNOPSIS
.B cpuplugd
.RI [ OPTIONS ]
.
.SH DESCRIPTION
The cpuplugd daemon dynamically enables and disables CPUs and increases or
decreases the cooperative memory management (CMM) page pool based on a set of
rules.

When the daemon is stopped, the size of the CMM page pool and the number
of active CPUs are reset to the values they had before the cpuplugd was started.

This program can be used to control the number of CPUs for Linux on z/VM
and for Linux in LPAR mode. The memory hotplug feature (CMM page pool) applies
to Linux on z/VM only.
.
.SH OPTIONS
.TP
\fB\-c\fP or \fB\-\-config\fP \fI<configuration file>\fP
Specify the absolute path to the configuration file. This option is mandatory.
The default configuration file can be found in /etc/cpuplugd.conf.
.
.TP
\fB\-f\fP or \fB\-\-foreground\fP
Run in the foreground and not as daemon. If this option is
omitted, the program runs in the background.
.
.TP
\fB\-h\fP or \fB\-\-help\fP
Print usage message and exit.
.
.TP
\fB\-v\fP or \fB\-\-version\fP
Print Version information and exit.
.
.TP
\fB\-V\fP or \fB\-\-verbose\fP
Print verbose messages to stdout (when running in foreground)
or to syslog otherwise.
This options is mainly used for debugging purposes.
.
.SH EXAMPLES
To test a setup start cpuplugd in foreground mode using verbose output:
.br
.RS 4
cpuplugd \-V \-f \-c /etc/cpuplugd.conf
.RE

For daemon mode, start cpuplugd from an init script as follows:
.br
.RS 4
cpuplugd \-c /etc/cpuplugd.conf
.RE
.SH SEE ALSO
.BR cpuplugd.conf (5)