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[thirdparty/systemd.git] / man / systemd-analyze.xml

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<refentry id="systemd-analyze"
    xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd-analyze</title>
    <productname>systemd</productname>

    <authorgroup>
      <author>
        <contrib>Developer</contrib>
        <firstname>Lennart</firstname>
        <surname>Poettering</surname>
        <email>lennart@poettering.net</email>
      </author>
      <author>
        <contrib>Developer</contrib>
        <firstname>Harald</firstname>
        <surname>Hoyer</surname>
        <email>harald@redhat.com</email>
      </author>
    </authorgroup>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd-analyze</refentrytitle>
    <manvolnum>1</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-analyze</refname>
    <refpurpose>Analyze and debug system manager</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg>time</arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">blame</arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">critical-chain</arg>
      <arg choice="opt" rep="repeat"><replaceable>UNIT</replaceable></arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">plot</arg>
      <arg choice="opt">&gt; file.svg</arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">dot</arg>
      <arg choice="opt" rep="repeat"><replaceable>PATTERN</replaceable></arg>
      <arg choice="opt">&gt; file.dot</arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">dump</arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">log-level</arg>
      <arg choice="opt"><replaceable>LEVEL</replaceable></arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">log-target</arg>
      <arg choice="opt"><replaceable>TARGET</replaceable></arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">syscall-filter</arg>
      <arg choice="opt"><replaceable>SET</replaceable>…</arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">verify</arg>
      <arg choice="opt" rep="repeat"><replaceable>FILES</replaceable></arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">calendar</arg>
      <arg choice="plain" rep="repeat"><replaceable>SPECS</replaceable></arg>
    </cmdsynopsis>
    <cmdsynopsis>
      <command>systemd-analyze</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="plain">service-watchdogs</arg>
      <arg choice="opt"><replaceable>BOOL</replaceable></arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><command>systemd-analyze</command> may be used to determine
    system boot-up performance statistics and retrieve other state and
    tracing information from the system and service manager, and to
    verify the correctness of unit files. It is also used to access
    special functions useful for advanced system manager debugging.</para>

    <para><command>systemd-analyze time</command> prints the time
    spent in the kernel before userspace has been reached, the time
    spent in the initial RAM disk (initrd) before normal system
    userspace has been reached, and the time normal system userspace
    took to initialize. Note that these measurements simply measure
    the time passed up to the point where all system services have
    been spawned, but not necessarily until they fully finished
    initialization or the disk is idle.</para>

    <para><command>systemd-analyze blame</command> prints a list of
    all running units, ordered by the time they took to initialize.
    This information may be used to optimize boot-up times. Note that
    the output might be misleading as the initialization of one
    service might be slow simply because it waits for the
    initialization of another service to complete.</para>

    <para><command>systemd-analyze critical-chain
    [<replaceable>UNIT…</replaceable>]</command> prints a tree of
    the time-critical chain of units (for each of the specified
    <replaceable>UNIT</replaceable>s or for the default target
    otherwise). The time after the unit is active or started is
    printed after the "@" character. The time the unit takes to start
    is printed after the "+" character. Note that the output might be
    misleading as the initialization of one service might depend on
    socket activation and because of the parallel execution of
    units.</para>

    <para><command>systemd-analyze plot</command> prints an SVG
    graphic detailing which system services have been started at what
    time, highlighting the time they spent on initialization.</para>

    <para><command>systemd-analyze dot</command> generates textual
    dependency graph description in dot format for further processing
    with the GraphViz
    <citerefentry project='die-net'><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
    tool. Use a command line like <command>systemd-analyze dot | dot
    -Tsvg > systemd.svg</command> to generate a graphical dependency
    tree. Unless <option>--order</option> or
    <option>--require</option> is passed, the generated graph will
    show both ordering and requirement dependencies. Optional pattern
    globbing style specifications (e.g. <filename>*.target</filename>)
    may be given at the end. A unit dependency is included in the
    graph if any of these patterns match either the origin or
    destination node.</para>

    <para><command>systemd-analyze dump</command> outputs a (usually
    very long) human-readable serialization of the complete server
    state. Its format is subject to change without notice and should
    not be parsed by applications.</para>

    <para><command>systemd-analyze log-level</command>
    prints the current log level of the <command>systemd</command> daemon.
    If an optional argument <replaceable>LEVEL</replaceable> is provided, then the command changes the current log
    level of the <command>systemd</command> daemon to <replaceable>LEVEL</replaceable> (accepts the same values as
    <option>--log-level=</option> described in
    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>).</para>

    <para><command>systemd-analyze log-target</command>
    prints the current log target of the <command>systemd</command> daemon.
    If an optional argument <replaceable>TARGET</replaceable> is provided, then the command changes the current log
    target of the <command>systemd</command> daemon to <replaceable>TARGET</replaceable> (accepts the same values as
    <option>--log-target=</option>, described in
    <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>).</para>

    <para><command>systemd-analyze syscall-filter <optional><replaceable>SET</replaceable>…</optional></command>
    will list system calls contained in the specified system call set <replaceable>SET</replaceable>,
    or all known sets if no sets are specified. Argument <replaceable>SET</replaceable> must include
    the <literal>@</literal> prefix.</para>

    <para><command>systemd-analyze verify</command> will load unit files and print
    warnings if any errors are detected. Files specified on the command line will be
    loaded, but also any other units referenced by them. The full unit search path is
    formed by combining the directories for all command line arguments, and the usual unit
    load paths (variable <varname>$SYSTEMD_UNIT_PATH</varname> is supported, and may be
    used to replace or augment the compiled in set of unit load paths; see
    <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
    All units files present in the directories containing the command line arguments will
    be used in preference to the other paths.</para>

    <para><command>systemd-analyze calendar</command> will parse and normalize repetitive calendar time events, and
    will calculate when they will elapse next. This takes the same input as the <varname>OnCalendar=</varname> setting
    in <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>, following the
    syntax described in
    <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>

    <para><command>systemd-analyze service-watchdogs</command>
    prints the current state of service runtime watchdogs of the <command>systemd</command> daemon.
    If an optional boolean argument is provided, then globally enables or disables the service
    runtime watchdogs (<option>WatchdogSec=</option>) and emergency actions (e.g.
    <option>OnFailure=</option> or <option>StartLimitAction=</option>); see
    <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
    The hardware watchdog is not affected by this setting.</para>

    <para>If no command is passed, <command>systemd-analyze
    time</command> is implied.</para>

  </refsect1>

  <refsect1>
    <title>Options</title>

    <para>The following options are understood:</para>

    <variablelist>
      <varlistentry>
        <term><option>--user</option></term>

        <listitem><para>Operates on the user systemd
        instance.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--system</option></term>

        <listitem><para>Operates on the system systemd instance. This
        is the implied default.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--order</option></term>
        <term><option>--require</option></term>

        <listitem><para>When used in conjunction with the
        <command>dot</command> command (see above), selects which
        dependencies are shown in the dependency graph. If
        <option>--order</option> is passed, only dependencies of type
        <varname>After=</varname> or <varname>Before=</varname> are
        shown. If <option>--require</option> is passed, only
        dependencies of type <varname>Requires=</varname>,
        <varname>Requisite=</varname>,
        <varname>Wants=</varname> and <varname>Conflicts=</varname>
        are shown. If neither is passed, this shows dependencies of
        all these types.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--from-pattern=</option></term>
        <term><option>--to-pattern=</option></term>

        <listitem><para>When used in conjunction with the
        <command>dot</command> command (see above), this selects which
        relationships are shown in the dependency graph. Both options
        require a
        <citerefentry project='die-net'><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>
        pattern as an argument, which will be matched against the
        left-hand and the right-hand, respectively, nodes of a
        relationship.</para>

        <para>Each of these can be used more than once, in which case
        the unit name must match one of the values. When tests for
        both sides of the relation are present, a relation must pass
        both tests to be shown. When patterns are also specified as
        positional arguments, they must match at least one side of the
        relation. In other words, patterns specified with those two
        options will trim the list of edges matched by the positional
        arguments, if any are given, and fully determine the list of
        edges shown otherwise.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--fuzz=</option><replaceable>timespan</replaceable></term>

        <listitem><para>When used in conjunction with the
        <command>critical-chain</command> command (see above), also
        show units, which finished <replaceable>timespan</replaceable>
        earlier, than the latest unit in the same level. The unit of
        <replaceable>timespan</replaceable> is seconds unless
        specified with a different unit, e.g.
        "50ms".</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--man=no</option></term>

        <listitem><para>Do not invoke man to verify the existence of
        man pages listed in <varname>Documentation=</varname>.
        </para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--generators</option></term>

        <listitem><para>Invoke unit generators, see
        <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
        Some generators require root privileges. When run under a
        normal users, enabling generators will generally result in
        some warnings.</para></listitem>
      </varlistentry>

      <xi:include href="user-system-options.xml" xpointer="host" />
      <xi:include href="user-system-options.xml" xpointer="machine" />

      <xi:include href="standard-options.xml" xpointer="help" />
      <xi:include href="standard-options.xml" xpointer="version" />
      <xi:include href="standard-options.xml" xpointer="no-pager" />
    </variablelist>

  </refsect1>

  <refsect1>
    <title>Exit status</title>

    <para>On success, 0 is returned, a non-zero failure code
    otherwise.</para>
  </refsect1>

  <refsect1>
    <title>Examples for <command>dot</command></title>

    <example>
      <title>Plots all dependencies of any unit whose name starts with
      <literal>avahi-daemon</literal></title>

      <programlisting>$ systemd-analyze dot 'avahi-daemon.*' | dot -Tsvg > avahi.svg
$ eog avahi.svg</programlisting>
    </example>

    <example>
      <title>Plots the dependencies between all known target units</title>

      <programlisting>$ systemd-analyze dot --to-pattern='*.target' --from-pattern='*.target' | dot -Tsvg > targets.svg
$ eog targets.svg</programlisting>
    </example>
  </refsect1>

  <refsect1>
    <title>Examples for <command>verify</command></title>

    <para>The following errors are currently detected:</para>
    <itemizedlist>
      <listitem><para>unknown sections and directives,
      </para></listitem>

      <listitem><para>missing dependencies which are required to start
      the given unit,</para></listitem>

      <listitem><para>man pages listed in
      <varname>Documentation=</varname> which are not found in the
      system,</para></listitem>

      <listitem><para>commands listed in <varname>ExecStart=</varname>
      and similar which are not found in the system or not
      executable.</para></listitem>
    </itemizedlist>

    <example>
      <title>Misspelt directives</title>

      <programlisting>$ cat ./user.slice
[Unit]
WhatIsThis=11
Documentation=man:nosuchfile(1)
Requires=different.service

[Service]
Description=x

$ systemd-analyze verify ./user.slice
[./user.slice:9] Unknown lvalue 'WhatIsThis' in section 'Unit'
[./user.slice:13] Unknown section 'Service'. Ignoring.
Error: org.freedesktop.systemd1.LoadFailed:
   Unit different.service failed to load:
   No such file or directory.
Failed to create user.slice/start: Invalid argument
user.slice: man nosuchfile(1) command failed with code 16
      </programlisting>
    </example>

    <example>
      <title>Missing service units</title>

      <programlisting>$ tail ./a.socket ./b.socket
==> ./a.socket &lt;==
[Socket]
ListenStream=100

==> ./b.socket &lt;==
[Socket]
ListenStream=100
Accept=yes

$ systemd-analyze verify ./a.socket ./b.socket
Service a.service not loaded, a.socket cannot be started.
Service b@0.service not loaded, b.socket cannot be started.
      </programlisting>
    </example>
  </refsect1>

  <xi:include href="less-variables.xml" />

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
    </para>
  </refsect1>

</refentry>