NAME¶

cpuplugd - Linux on System z CPU and memory hotplug daemon

SYNOPSIS¶

cpuplugd [OPTIONS]

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.

The cpuplugd daemon stops any CPU hot-plug operations when the system switches to vertical polarization, thus avoiding possible performance penalties.

OPTIONS¶

-c or --config <configuration file>

Specify the absolute path to the configuration file. This option is mandatory. The default configuration file can be found in /etc/cpuplugd.conf.

-f or --foreground

Run in the foreground and not as daemon. If this option is omitted, the program runs in the background.

-h or --help

Print usage message and exit.

-v or --version

Print Version information and exit.

-V or --verbose

Print verbose messages to stdout (when running in foreground) or to syslog otherwise. This options is mainly used for debugging purposes.

EXAMPLES¶

To test a setup start cpuplugd in foreground mode using verbose output:

For daemon mode, start cpuplugd from an init script as follows:

SEE ALSO¶

cpuplugd.conf(5)