systemd.slice - Man Page

Slice unit configuration

A unit configuration file whose name ends in ".slice" encodes information about a slice unit. A slice unit is a concept for hierarchically managing resources of a group of processes. This management is performed by creating a node in the Linux Control Group (cgroup) tree. Units that manage processes (primarily scope and service units) may be assigned to a specific slice. For each slice, certain resource limits may be set that apply to all processes of all units contained in that slice. Slices are organized hierarchically in a tree. The name of the slice encodes the location in the tree. The name consists of a dash-separated series of names, which describes the path to the slice from the root slice. The root slice is named -.slice. Example: foo-bar.slice is a slice that is located within foo.slice, which in turn is located in the root slice -.slice.

Note that slice units cannot be templated, nor is possible to add multiple names to a slice unit by creating additional symlinks to its unit file.

By default, service and scope units are placed in system.slice, virtual machines and containers registered with systemd-machined(8) are found in machine.slice, and user sessions handled by systemd-logind(8) in user.slice. See systemd.special(7) for more information.

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 slice specific configuration options are configured in the [Slice] section. Currently, only generic resource control settings as described in systemd.resource-control(5) are allowed.

See the New Control Group Interfaces^[1] for an introduction on how to make use of slice units from programs.

Automatic Dependencies

Implicit Dependencies

The following dependencies are implicitly added:

Slice units automatically gain dependencies of type After= and Requires= on their immediate parent slice unit.

Default Dependencies

The following dependencies are added unless DefaultDependencies=no is set:

Slice units will automatically have dependencies of type Conflicts= and Before= on shutdown.target. These ensure that slice units are removed prior to system shutdown. Only slice units involved with late system shutdown should disable DefaultDependencies= option.

Options

Slice unit files may include [Unit] and [Install] sections, which are described in systemd.unit(5). No options specific to this file type are supported.