user@.service(5) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | CONTROLLING RESOURCES FOR LOGGED-IN USERS | EXAMPLES | SEE ALSO | COLOPHON

USER@.SERVICE(5)              user@.service             USER@.SERVICE(5)

NAME         top

       user@.service, user-runtime-dir@.service, systemd-user-runtime-
       dir - System units to start the user manager

SYNOPSIS         top

       user@UID.service

       user-runtime-dir@UID.service

       /usr/lib/systemd/systemd-user-runtime-dir

       user-UID.slice

DESCRIPTION         top

       The systemd(1) system manager (PID 1) starts user manager
       instances as user@UID.service, with the user's numerical UID used
       as the instance identifier. These instances use the same
       executable as the system manager, but running in a mode where it
       starts a different set of units. Each systemd --user instance
       manages a hierarchy of units specific to that user. See
       systemd(1) for a discussion of units and systemd.special(7) for a
       list of units that form the basis of the unit hierarchies of
       system and user units.

       user@UID.service is accompanied by the system unit
       user-runtime-dir@UID.service, which creates the user's runtime
       directory /run/user/UID, and then removes it when this unit is
       stopped.  user-runtime-dir@UID.service executes the
       systemd-user-runtime-dir binary to do the actual work.

       User processes may be started by the user@.service instance, in
       which case they will be part of that unit in the system
       hierarchy. They may also be started elsewhere, for example by
       sshd(8) or a display manager like gdm, in which case they form a
       .scope unit (see systemd.scope(5)). Both user@UID.service and the
       scope units are collected under the user-UID.slice.

       Individual user-UID.slice slices are collected under user.slice,
       see systemd.special(7).

CONTROLLING RESOURCES FOR LOGGED-IN USERS         top

       Options that control resources available to logged-in users can
       be configured at a few different levels. As described in the
       previous section, user.slice contains processes of all users, so
       any resource limits on that slice apply to all users together.
       The usual way to configure them would be through drop-ins, e.g.
       /etc/systemd/system/user.slice.d/resources.conf.

       The processes of a single user are collected under
       user-UID.slice. Resource limits for that user can be configured
       through drop-ins for that unit, e.g.
       /etc/systemd/system/user-1000.slice.d/resources.conf. If the
       limits should apply to all users instead, they may be configured
       through drop-ins for the truncated unit name, user-.slice. For
       example, configuration in
       /etc/systemd/system/user-.slice.d/resources.conf is included in
       all user-UID.slice units, see systemd.unit(5) for a discussion of
       the drop-in mechanism.

       When a user logs in and a .scope unit is created for the session
       (see previous section), the creation of the scope may be managed
       through pam_systemd(8). This PAM module communicates with
       systemd-logind(8) to create the session scope and provide access
       to hardware resources. Resource limits for the scope may be
       configured through the PAM module configuration, see
       pam_systemd(8). Configuring them through the normal unit
       configuration is also possible, but since the name of the slice
       unit is generally unpredictable, this is less useful.

       In general any resources that apply to units may be set for
       user@UID.service and the slice units discussed above, see
       systemd.resource-control(5) for an overview.

EXAMPLES         top

       Example 1. Hierarchy of control groups with two logged in users

           $ systemd-cgls
           Control group /:
           -.slice
           ├─user.slice
           │ ├─user-1000.slice
           │ │ ├─user@1000.service
           │ │ │ ├─pulseaudio.service
           │ │ │ │ └─2386 /usr/bin/pulseaudio --daemonize=no
           │ │ │ └─gnome-terminal-server.service
           │ │ │   └─init.scope
           │ │ │     ├─ 4127 /usr/libexec/gnome-terminal-server
           │ │ │     └─ 4198 zsh
           │ │ ...
           │ │ └─session-4.scope
           │ │   ├─ 1264 gdm-session-worker [pam/gdm-password]
           │ │   ├─ 2339 /usr/bin/gnome-shell
           │ │   ...
           │ │ ├─session-19.scope
           │ │   ├─6497 sshd: zbyszek [priv]
           │ │   ├─6502 sshd: zbyszek@pts/6
           │ │   ├─6509 -zsh
           │ │   └─6602 systemd-cgls --no-pager
           │ ...
           │ └─user-1001.slice
           │   ├─session-20.scope
           │   │ ├─6675 sshd: guest [priv]
           │   │ ├─6708 sshd: guest@pts/6
           │   │ └─6717 -bash
           │   └─user@1001.service
           │     ├─init.scope
           │     │ ├─6680 /usr/lib/systemd/systemd --user
           │     │ └─6688 (sd-pam)
           │     └─sleep.service
           │       └─6706 /usr/bin/sleep 30
           ...

       User with UID 1000 is logged in using gdm (session-4.scope) and
       ssh(1) (session-19.scope), and also has a user manager instance
       running (user@1000.service). User with UID 1001 is logged in
       using ssh (session-20.scope) and also has a user manager instance
       running (user@1001.service). Those are all (leaf) system units,
       and form part of the slice hierarchy, with user-1000.slice and
       user-1001.slice below user.slice. User units are visible below
       the user@.service instances (pulseaudio.service,
       gnome-terminal-server.service, init.scope, sleep.service).

       Example 2. Default user resource limits

           $ systemctl cat user-1000.slice
           # /usr/lib/systemd/system/user-.slice.d/10-defaults.conf
           # ...
           [Unit]
           Description=User Slice of UID %j
           After=systemd-user-sessions.service

           [Slice]
           TasksMax=33%

       The user-UID.slice units by default don't have a unit file. The
       resource limits are set through a drop-in, which can be easily
       replaced or extended following standard drop-in mechanisms
       discussed in the first section.

SEE ALSO         top

       systemd(1), systemd.service(5), systemd.slice(5),
       systemd.resource-control(5), systemd.exec(5), systemd.special(7),
       pam(8)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2020-12-18.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2020-12-18.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

systemd 247                                             USER@.SERVICE(5)

Pages that refer to this page: systemd(1)systemd.directives(7)systemd.index(7)systemd.special(7)