Systemd/man/systemd-analyze.xml

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<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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Copyright 2012 Lennart Poettering
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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>
</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>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>
</variablelist>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success 0 is returned, a non-zero failure
code otherwise.</para>
</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>