SYSTEMD.SWAP(5)systemd.swapSYSTEMD.SWAP(5)NAMEsystemd.swap - systemd swap configuration files
SYNOPSISsystemd.swapDESCRIPTION
A unit configuration file whose name ends in .swap encodes information
about a swap device or file for memory paging controlled and supervised
by systemd.
This man page lists the configuration options specific to this unit
type. See systemd.unit(5) for the common options of all unit
configuration files. The common configuration items are configured in
the generic [Unit] and [Install] sections. The swap specific
configuration options are configured in the [Swap] section.
Swap units must be named after the devices (resp. files) they control.
Example: the swap device /dev/sda5 must be configured in a unit file
dev-sda5.swap. For details about the escaping logic used to convert a
file system path to a unit name see systemd.unit(5).
All swap units automatically get the appropriate dependencies on the
devices (resp. on the mount points of the files) they are activated
from.
Swap units with DefaultDependencies= enabled implicitly acquire a
conflicting dependency to umount.target so that they are deactivated at
shutdown.
FSTAB
Swap units may either be configured via unit files, or via /etc/fstab
(see fstab(5) for details).
If a swap device or file is configured in both /etc/fstab and a unit
file the configuration in the latter takes precedence.
Unless the noauto option is set for them all swap units configured in
/etc/fstab are also added as requirements to swap.target, so that they
are waited for and activated during boot.
OPTIONS
Swap files must include a [Swap] section, which carries information
about the swap device it supervises. A number of options that may be
used in this section are shared with other unit types. These options
are documented in systemd.exec(5). The options specific to the [Swap]
section of swap units are the following:
What=
Takes an absolute path of a device node or file to use for paging.
See swapon(8) for details. If this refers to a device node, a
dependency on the respective device unit is automatically created.
(See systemd.device(5) for more information.) If this refers to a
file, a dependency on the respective mount unit is automatically
created. (See systemd.mount(5) for more information.) This option
is mandatory.
Priority=
Swap priority to use when activating the swap device or file. This
takes an integer. This setting is optional.
TimeoutSec=
Configures the time to wait for the swapon command to finish. If a
command does not exit within the configured time the swap will be
considered failed and be shut down again. All commands still
running will be terminated forcibly via SIGTERM, and after another
delay of this time with SIGKILL. (See KillMode= below.) Takes a
unit-less value in seconds, or a time span value such as "5min
20s". Pass 0 to disable the timeout logic. Defaults to 90s.
KillMode=
Specifies how processes of this swap shall be killed. One of
control-group, process, none.
This option is mostly equivalent to the KillMode= option of service
files. See systemd.service(5) for details.
KillSignal=
Specifies which signal to use when killing a process of this swap.
Defaults to SIGTERM.
SendSIGKILL=
Specifies whether to send SIGKILL to remaining processes after a
timeout, if the normal shutdown procedure left processes of the
swap around. Takes a boolean value. Defaults to "yes".
SEE ALSOsystemd(1), systemctl(8), systemd.unit(5), systemd.exec(5),
systemd.device(5), systemd.mount(5), swapon(8)AUTHOR
Lennart Poettering <lennart@poettering.net>
Developer
systemd 03/16/2012 SYSTEMD.SWAP(5)
