systemd.slice man page
systemd.slice — Slice unit configuration
A unit configuration file whose name ends in ".slice" encodes information about a slice which 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 it.
By default, service and scope units are placed in system.slice, virtual machines and containers registered with systemd-machined(1) are found in machine.slice, and user sessions handled by systemd-logind(1) in user.slice. See systemd.special(5) 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 for an introduction on how to make use of slice units from programs.
Slice units automatically gain dependencies of type After= and Requires= on their immediate parent slice unit.
Unless DefaultDependencies=false is used in the "[Unit]" section, slice units will implicitly 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 early boot or late system shutdown should disable this option.
systemd(1), systemd.unit(5), systemd.resource-control(5), systemd.service(5), systemd.scope(5), systemd.special(7), systemd.directives(7)
New Control Group Interfaces
pam_systemd(8), sd_bus_creds_get_pid(3), sd_pid_get_session(3), systemd(1), systemd.directives(7), systemd.index(7), systemd-nspawn(1), systemd.resource-control(5), systemd-run(1), systemd.service(5), systemd.special(7), systemd.unit(5).