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systemd.swap(5) [debian man page]

SYSTEMD.SWAP(5) 						   systemd.swap 						   SYSTEMD.SWAP(5)

NAME
systemd.swap - systemd swap configuration files SYNOPSIS
systemd.swap DESCRIPTION
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 ALSO
systemd(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 10/07/2013 SYSTEMD.SWAP(5)

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SYSTEMD.SWAP(5) 						   systemd.swap 						   SYSTEMD.SWAP(5)

NAME
systemd.swap - Swap unit configuration SYNOPSIS
swap.swap DESCRIPTION
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. Additional options are listed in systemd.exec(5), which define the execution environment the swapon(8) program is executed in, in systemd.kill(5), which define the way these processes are terminated, and in systemd.resource-control(5), which configure resource control settings for these processes of the unit. Swap units must be named after the devices or 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). Note that swap units cannot be templated, nor is possible to add multiple names to a swap unit by creating additional symlinks to it. IMPLICIT DEPENDENCIES
The following dependencies are implicitly added: o All swap units automatically get the BindsTo= and After= dependencies on the device units or the mount units of the files they are activated from. Additional implicit dependencies may be added as result of execution and resource control parameters as documented in systemd.exec(5) and systemd.resource-control(5). DEFAULT DEPENDENCIES
The following dependencies are added unless DefaultDependencies=no is set: o Swap units automatically acquire a Conflicts= and a Before= dependency on umount.target so that they are deactivated at shutdown as well as a Before=swap.target dependency. FSTAB
Swap units may either be configured via unit files, or via /etc/fstab (see fstab(5) for details). Swaps listed in /etc/fstab will be converted into native units dynamically at boot and when the configuration of the system manager is reloaded. See systemd-fstab- generator(8) for details about the conversion. If a swap device or file is configured in both /etc/fstab and a unit file, the configuration in the latter takes precedence. When reading /etc/fstab, a few special options are understood by systemd which influence how dependencies are created for swap units. noauto, auto With noauto, the swap unit will not be added as a dependency for swap.target. This means that it will not be activated automatically during boot, unless it is pulled in by some other unit. The auto option has the opposite meaning and is the default. nofail With nofail, the swap unit will be only wanted, not required by swap.target. This means that the boot will continue even if this swap device is not activated successfully. 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) and systemd.kill(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. Note that the usual specifier expansion is applied to this setting, literal percent characters should hence be written as "%%". Priority= Swap priority to use when activating the swap device or file. This takes an integer. This setting is optional and ignored when the priority is set by pri= in the Options= key. Options= May contain an option string for the swap device. This may be used for controlling discard options among other functionality, if the swap backing device supports the discard or trim operation. (See swapon(8) for more information.) Note that the usual specifier expansion is applied to this setting, literal percent characters should hence be written as "%%". 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= in systemd.kill(5).) 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 DefaultTimeoutStartSec= from the manager configuration file (see systemd- system.conf(5)). Check systemd.exec(5) and systemd.kill(5) for more settings. SEE ALSO
systemd(1), systemctl(1), systemd.unit(5), systemd.exec(5), systemd.kill(5), systemd.resource-control(5), systemd.device(5), systemd.mount(5), swapon(8), systemd-fstab-generator(8), systemd.directives(7) systemd 237 SYSTEMD.SWAP(5)
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