dbus-manager.c: log error, why switch-root is refused

[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>
                </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 <arg choice="opt" rep="repeat">OPTIONS</arg> time</command>
                </cmdsynopsis>
                <cmdsynopsis>
                        <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> blame </command>
                </cmdsynopsis>
                <cmdsynopsis>
                        <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> plot <arg choice="opt">&gt; file.svg</arg></command>
                </cmdsynopsis>
                <cmdsynopsis>
                        <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> dot <arg choice="opt">pattern...</arg> </command>
                </cmdsynopsis>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para><command>systemd-analyze</command> may be used
                to determine system boot-up performance of the current
                boot.</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 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> Generate
                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>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, 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), 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 lefthand and
                                righthand, respectively, nodes of a
                                relationship. Each of these can be
                                used more than once which means a
                                unit name must match one of given
                                values.</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>See Also</title>
                <para>
                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                        <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
                </para>
        </refsect1>

</refentry>