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

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        "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

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<refentry id="systemd-analyze">

        <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 system boot-up performance</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">set-log-level</arg>
                        <arg choice="opt"><replaceable>LEVEL</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.</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><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 set-log-level
                <replaceable>LEVEL</replaceable></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>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>-h</option></term>
                                <term><option>--help</option></term>

                                <listitem><para>Prints a short help
                                text and exits.</para></listitem>
                        </varlistentry>

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

                                <listitem><para>Shows performance data
                                of user sessions instead of the system
                                manager.</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>RequiresOverridable=</varname>,
                                <varname>Requisite=</varname>,
                                <varname>RequisiteOverridable=</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.
                                They both require
                                <citerefentry><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                                patterns as arguments, which are
                                matched against left-hand and
                                right-hand, respectively, nodes of a
                                relationship. Each of these can be
                                used more than once, which means a
                                unit name must match one of the given
                                values.</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>--no-pager</option></term>

                                <listitem>
                                        <para>Do not pipe output into a pager.</para>
                                </listitem>
                        </varlistentry>
                </variablelist>

        </refsect1>

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

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

        <refsect1>
                <title>Examples</title>

                <para>This plots all dependencies of any unit whose
                name starts with <literal>avahi-daemon.</literal>:</para>

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

                <para>This plots the dependencies between all known target units:</para>

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


        </refsect1>

        <refsect1>
                <title>Environment</title>

                <variablelist class='environment-variables'>
                        <varlistentry>
                                <term><varname>$SYSTEMD_PAGER</varname></term>

                                <listitem>
                                        <para>Pager to use when <option>--no-pager</option> is not
                                        given; overrides <varname>$PAGER</varname>.  Setting this to
                                        an empty string or the value <literal>cat</literal> is
                                        equivalent to passing
                                        <option>--no-pager</option>.</para>
                                </listitem>
                        </varlistentry>
                </variablelist>
        </refsect1>

        <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>