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.
   7
   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                         <author>
  38                                 <contrib>Developer</contrib>
  39                                 <firstname>Harald</firstname>
  40                                 <surname>Hoyer</surname>
  41                                 <email>harald@redhat.com</email>
  42                         </author>
  43                 </authorgroup>
  44         </refentryinfo>
  45
  46         <refmeta>
  47                 <refentrytitle>systemd-analyze</refentrytitle>
  48                 <manvolnum>1</manvolnum>
  49         </refmeta>
  50
  51         <refnamediv>
  52                 <refname>systemd-analyze</refname>
  53                 <refpurpose>Analyze system boot-up performance</refpurpose>
  54         </refnamediv>
  55
  56         <refsynopsisdiv>
  57                 <cmdsynopsis>
  58                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> time</command>
  59                 </cmdsynopsis>
  60                 <cmdsynopsis>
  61                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> blame </command>
  62                 </cmdsynopsis>
  63                 <cmdsynopsis>
  64                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> critical-chain </command>
  65                 </cmdsynopsis>
  66                 <cmdsynopsis>
  67                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> plot <arg choice="opt">&gt; file.svg</arg></command>
  68                 </cmdsynopsis>
  69                 <cmdsynopsis>
  70                         <command>systemd-analyze <arg choice="opt" rep="repeat">OPTIONS</arg> dot <arg choice="opt">pattern...</arg> </command>
  71                 </cmdsynopsis>
  72         </refsynopsisdiv>
  73
  74         <refsect1>
  75                 <title>Description</title>
  76
  77                 <para><command>systemd-analyze</command> may be used
  78                 to determine system boot-up performance of the current
  79                 boot.</para>
  80
  81                 <para><command>systemd-analyze time</command>
  82                 prints the time spent in the kernel before
  83                 userspace has been reached, the time spent in the
  84                 initial RAM disk (initrd) before normal system
  85                 userspace has been reached and the time normal system
  86                 userspace took to initialize. Note that these
  87                 measurements simply measure the time passed up to the
  88                 point where all system services have been spawned, but
  89                 not necessarily until they fully finished
  90                 initialization or the disk is idle.</para>
  91
  92                 <para><command>systemd-analyze blame</command> prints
  93                 a list of all running units, ordered by the time they
  94                 took to initialize. This information may be used to
  95                 optimize boot-up times. Note that the output might be
  96                 misleading as the initialization of one service might
  97                 be slow simply because it waits for the initialization
  98                 of another service to complete.</para>
  99
 100                 <para><command>systemd-analyze critical-chain</command>
 101                 prints a tree of the time critical chain of units.
 102                 The time after the unit is active or started is printed
 103                 after the "@" character. The time the unit takes to
 104                 start is printed after the "+" character.
 105                 Note that the output might be misleading as the
 106                 initialization of one service might depend on socket
 107                 activation and because of the parallel execution
 108                 of units.</para>
 109
 110                 <para><command>systemd-analyze plot</command> prints
 111                 an SVG graphic detailing which system services have
 112                 been started at what time, highlighting the time they
 113                 spent on initialization.</para>
 114
 115                 <para><command>systemd-analyze dot</command> Generate
 116                 textual dependency graph description in dot format for
 117                 further processing with the GraphViz
 118                 <citerefentry><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 119                 tool. Use a command line like <command>systemd-analyze
 120                 dot | dot -Tsvg > systemd.svg</command> to generate a
 121                 graphical dependency tree. Unless
 122                 <option>--order</option> or <option>--require</option>
 123                 is passed the generated graph will show both ordering
 124                 and requirement dependencies. Optional pattern
 125                 globbing style specifications
 126                 (e.g. <filename>*.target</filename>) may be given at
 127                 the end. A unit dependency is included in the graph if
 128                 any of these patterns match either the origin or
 129                 destination node.</para>
 130
 131                 <para>If no command is passed <command>systemd-analyze
 132                 time</command> is implied.</para>
 133
 134         </refsect1>
 135
 136         <refsect1>
 137                 <title>Options</title>
 138
 139                 <para>The following options are understood:</para>
 140
 141                 <variablelist>
 142                         <varlistentry>
 143                                 <term><option>-h</option></term>
 144                                 <term><option>--help</option></term>
 145
 146                                 <listitem><para>Prints a short help
 147                                 text and exits.</para></listitem>
 148                         </varlistentry>
 149
 150                         <varlistentry>
 151                                 <term><option>--user</option></term>
 152
 153                                 <listitem><para>Shows performance data
 154                                 of user sessions instead of the system
 155                                 manager.</para></listitem>
 156                         </varlistentry>
 157
 158                         <varlistentry>
 159                                 <term><option>--order</option></term>
 160                                 <term><option>--require</option></term>
 161
 162                                 <listitem><para>When used in
 163                                 conjunction with the
 164                                 <command>dot</command> command (see
 165                                 above), selects which dependencies are
 166                                 shown in the dependency graph. If
 167                                 <option>--order</option> is passed
 168                                 only dependencies of type
 169                                 <varname>After=</varname> or
 170                                 <varname>Before=</varname> are
 171                                 shown. If <option>--require</option>
 172                                 is passed only dependencies of type
 173                                 <varname>Requires=</varname>,
 174                                 <varname>RequiresOverridable=</varname>,
 175                                 <varname>Requisite=</varname>,
 176                                 <varname>RequisiteOverridable=</varname>,
 177                                 <varname>Wants=</varname> and
 178                                 <varname>Conflicts=</varname> are
 179                                 shown. If neither is passed, shows
 180                                 dependencies of all these
 181                                 types.</para></listitem>
 182                         </varlistentry>
 183
 184                         <varlistentry>
 185                                 <term><option>--from-pattern=</option></term>
 186                                 <term><option>--to-pattern=</option></term>
 187
 188                                 <listitem><para>When used in
 189                                 conjunction with the
 190                                 <command>dot</command> command (see
 191                                 above), selects which relationships
 192                                 are shown in the dependency graph.
 193                                 They both require
 194                                 <citerefentry><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 195                                 patterns as arguments, which are
 196                                 matched against lefthand and
 197                                 righthand, respectively, nodes of a
 198                                 relationship. Each of these can be
 199                                 used more than once which means a
 200                                 unit name must match one of given
 201                                 values.</para></listitem>
 202                         </varlistentry>
 203
 204                         <varlistentry>
 205                                 <term><option>--fuzz=</option><replaceable>timespan</replaceable></term>
 206
 207                                 <listitem><para>When used in conjunction
 208                                 with the <command>critical-chain</command>
 209                                 command (see above), also show units, which
 210                                 finished <replaceable>timespan</replaceable> earlier, than the
 211                                 latest unit in the same level. The unit of
 212                                 <replaceable>timespan</replaceable> is seconds
 213                                 unless specified with a different unit,
 214                                 i.e. "50ms".</para></listitem>
 215                         </varlistentry>
 216                 </variablelist>
 217
 218         </refsect1>
 219
 220         <refsect1>
 221                 <title>Exit status</title>
 222
 223                 <para>On success 0 is returned, a non-zero failure
 224                 code otherwise.</para>
 225         </refsect1>
 226
 227         <refsect1>
 228                 <title>Examples</title>
 229
 230                 <para>This plots all dependencies of any unit whose
 231                 name starts with "<literal>avahi-daemon.</literal>":</para>
 232
 233                 <programlisting>$ systemd-analyze dot 'avahi-daemon.*' | dot -Tsvg > avahi.svg
 234 $ eog avahi.svg</programlisting>
 235
 236                 <para>This plots the dependencies between all known target units:</para>
 237
 238                 <programlisting>systemd-analyze dot --to-pattern='*.target' --from-patter='*.target' | dot -Tsvg > targets.svg
 239 $ eog targets.svg</programlisting>
 240
 241
 242         </refsect1>
 243
 244         <refsect1>
 245                 <title>See Also</title>
 246                 <para>
 247                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 248                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 249                 </para>
 250         </refsect1>
 251
 252 </refentry>