man/systemd-analyze.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
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   6   This file is part of systemd.
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   8   Copyright 2012 Lennart Poettering
   9
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  23
  24 <refentry id="systemd-analyze">
  25
  26         <refentryinfo>
  27                 <title>systemd-analyze</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Lennart</firstname>
  34                                 <surname>Poettering</surname>
  35                                 <email>lennart@poettering.net</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>systemd-analyze</refentrytitle>
  42                 <manvolnum>1</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd-analyze</refname>
  47                 <refpurpose>Analyze system boot-up performance</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <cmdsynopsis>
  52                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> time</command>
  53                 </cmdsynopsis>
  54                 <cmdsynopsis>
  55                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> blame </command>
  56                 </cmdsynopsis>
  57                 <cmdsynopsis>
  58                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> plot <arg choice="opt">&gt; file.svg</arg></command>
  59                 </cmdsynopsis>
  60         </refsynopsisdiv>
  61
  62         <refsect1>
  63                 <title>Description</title>
  64
  65                 <para><command>systemd-analyze</command> may be used
  66                 to determine system boot-up performance of the current
  67                 boot.</para>
  68
  69                 <para><command>systemd-analyze time</command>
  70                 prints the time spent in the kernel before
  71                 userspace has been reached, the time spent in the
  72                 initial RAM disk (initrd) before normal system
  73                 userspace has been reached and the time normal system
  74                 userspace took to initialize. Note that these
  75                 measurements simply measure the time passed up to the
  76                 point where all system services have been spawned, but
  77                 not necessarily until they fully finished
  78                 initialization or the disk is idle.</para>
  79
  80                 <para><command>systemd-analyze blame</command> prints
  81                 a list of all running units, ordered by the time they
  82                 took to initialize. This information may be used to
  83                 optimize boot-up times. Note that the output might be
  84                 misleading as the initialization of one service might
  85                 be slow simply because it waits for the initialization
  86                 of another service to complete.</para>
  87
  88                 <para><command>systemd-analyze plot</command> prints
  89                 an SVG graphic detailing which system services have
  90                 been started at what time, highlighting the time they
  91                 spent on initialization.</para>
  92
  93                 <para>If no command is passed <command>systemd-analyze
  94                 time</command> is implied.</para>
  95
  96         </refsect1>
  97
  98         <refsect1>
  99                 <title>Options</title>
 100
 101                 <para>The following options are understood:</para>
 102
 103                 <variablelist>
 104                         <varlistentry>
 105                                 <term><option>-h</option></term>
 106                                 <term><option>--help</option></term>
 107
 108                                 <listitem><para>Prints a short help
 109                                 text and exits.</para></listitem>
 110                         </varlistentry>
 111
 112                         <varlistentry>
 113                                 <term><option>--user</option></term>
 114
 115                                 <listitem><para>Shows performance data
 116                                 of user sessions instead of the system
 117                                 manager.</para></listitem>
 118                         </varlistentry>
 119                 </variablelist>
 120
 121         </refsect1>
 122
 123         <refsect1>
 124                 <title>Exit status</title>
 125
 126                 <para>On success 0 is returned, a non-zero failure
 127                 code otherwise.</para>
 128         </refsect1>
 129
 130         <refsect1>
 131                 <title>See Also</title>
 132                 <para>
 133                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 134                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 135                 </para>
 136         </refsect1>
 137
 138 </refentry>