man/systemd.slice.xml

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   8   Copyright 2013 Zbigniew Jędrzejewski-Szmek
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  23
  24 <refentry id="systemd.slice">
  25   <refentryinfo>
  26     <title>systemd.slice</title>
  27     <productname>systemd</productname>
  28
  29     <authorgroup>
  30       <author>
  31         <contrib>Developer</contrib>
  32         <firstname>Lennart</firstname>
  33         <surname>Poettering</surname>
  34         <email>lennart@poettering.net</email>
  35       </author>
  36     </authorgroup>
  37   </refentryinfo>
  38
  39   <refmeta>
  40     <refentrytitle>systemd.slice</refentrytitle>
  41     <manvolnum>5</manvolnum>
  42   </refmeta>
  43
  44   <refnamediv>
  45     <refname>systemd.slice</refname>
  46     <refpurpose>Slice unit configuration</refpurpose>
  47   </refnamediv>
  48
  49   <refsynopsisdiv>
  50     <para><filename><replaceable>slice</replaceable>.slice</filename></para>
  51   </refsynopsisdiv>
  52
  53   <refsect1>
  54     <title>Description</title>
  55
  56     <para>A unit configuration file whose name ends in
  57     <literal>.slice</literal> encodes information about a slice which
  58     is a concept for hierarchically managing resources of a group of
  59     processes. This management is performed by creating a node in the
  60     Linux Control Group (cgroup) tree. Units that manage processes
  61     (primarily scope and service units) may be assigned to a specific
  62     slice. For each slice, certain resource limits may be set that
  63     apply to all processes of all units contained in that
  64     slice. Slices are organized hierarchically in a tree. The name of
  65     the slice encodes the location in the tree. The name consists of a
  66     dash-separated series of names, which describes the path to the
  67     slice from the root slice. The root slice is named,
  68     <filename>-.slice</filename>. Example:
  69     <filename>foo-bar.slice</filename> is a slice that is located
  70     within <filename>foo.slice</filename>, which in turn is located in
  71     the root slice <filename>-.slice</filename>.
  72     </para>
  73
  74     <para>By default, service and scope units are placed in
  75     <filename>system.slice</filename>, virtual machines and containers
  76     registered with
  77     <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  78     are found in <filename>machine.slice</filename>, and user sessions
  79     handled by
  80     <citerefentry><refentrytitle>systemd-logind</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  81     in <filename>user.slice</filename>. See
  82     <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  83     for more information.</para>
  84
  85     <para>See
  86     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  87     for the common options of all unit configuration
  88     files. The common configuration items are configured
  89     in the generic [Unit] and [Install] sections. The
  90     slice specific configuration options are configured in
  91     the [Slice] section. Currently, only generic resource control settings
  92     as described in
  93     <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> are allowed.
  94     </para>
  95
  96     <para>See the <ulink
  97     url="http://www.freedesktop.org/wiki/Software/systemd/ControlGroupInterface/">New
  98     Control Group Interfaces</ulink> for an introduction on how to make
  99     use of slice units from programs.</para>
 100
 101     <para>Unless <varname>DefaultDependencies=false</varname>
 102     is used, slice units will implicitly have dependencies of
 103     type <varname>Conflicts=</varname> and
 104     <varname>Before=</varname> on
 105     <filename>shutdown.target</filename>. These ensure
 106     that slice units are removed prior to system
 107     shutdown. Only slice units involved with early boot or
 108     late system shutdown should disable this option.
 109     </para>
 110   </refsect1>
 111
 112   <refsect1>
 113     <title>See Also</title>
 114     <para>
 115       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 116       <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 117       <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 118       <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 119       <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 120       <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 121       <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 122     </para>
 123   </refsect1>
 124
 125 </refentry>