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                         <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</command>
  59                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  60                         <arg>time</arg>
  61                 </cmdsynopsis>
  62                 <cmdsynopsis>
  63                         <command>systemd-analyze</command>
  64                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  65                         <arg choice="plain">blame</arg>
  66                 </cmdsynopsis>
  67                 <cmdsynopsis>
  68                         <command>systemd-analyze</command>
  69                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  70                         <arg choice="plain">critical-chain</arg>
  71                         <arg choice="opt" rep="repeat"><replaceable>UNIT</replaceable></arg>
  72                 </cmdsynopsis>
  73                 <cmdsynopsis>
  74                         <command>systemd-analyze</command>
  75                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  76                         <arg choice="plain">plot</arg>
  77                         <arg choice="opt">&gt; file.svg</arg>
  78                 </cmdsynopsis>
  79                 <cmdsynopsis>
  80                         <command>systemd-analyze</command>
  81                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  82                         <arg choice="plain">dot</arg>
  83                         <arg choice="opt" rep="repeat"><replaceable>PATTERN</replaceable></arg>
  84                 </cmdsynopsis>
  85         </refsynopsisdiv>
  86
  87         <refsect1>
  88                 <title>Description</title>
  89
  90                 <para><command>systemd-analyze</command> may be used
  91                 to determine system boot-up performance of the current
  92                 boot.</para>
  93
  94                 <para><command>systemd-analyze time</command>
  95                 prints the time spent in the kernel before
  96                 userspace has been reached, the time spent in the
  97                 initial RAM disk (initrd) before normal system
  98                 userspace has been reached, and the time normal system
  99                 userspace took to initialize. Note that these
 100                 measurements simply measure the time passed up to the
 101                 point where all system services have been spawned, but
 102                 not necessarily until they fully finished
 103                 initialization or the disk is idle.</para>
 104
 105                 <para><command>systemd-analyze blame</command> prints
 106                 a list of all running units, ordered by the time they
 107                 took to initialize. This information may be used to
 108                 optimize boot-up times. Note that the output might be
 109                 misleading as the initialization of one service might
 110                 be slow simply because it waits for the initialization
 111                 of another service to complete.</para>
 112
 113                 <para><command>systemd-analyze critical-chain [<replaceable>UNIT...</replaceable>]</command>
 114                 prints a tree of the time-critical chain of units
 115                 (for each of the specified <replaceable>UNIT</replaceable>s
 116                 or for the default target otherwise).
 117                 The time after the unit is active or started is printed
 118                 after the "@" character. The time the unit takes to
 119                 start is printed after the "+" character.
 120                 Note that the output might be misleading as the
 121                 initialization of one service might depend on socket
 122                 activation and because of the parallel execution
 123                 of units.</para>
 124
 125                 <para><command>systemd-analyze plot</command> prints
 126                 an SVG graphic detailing which system services have
 127                 been started at what time, highlighting the time they
 128                 spent on initialization.</para>
 129
 130                 <para><command>systemd-analyze dot</command> Generate
 131                 textual dependency graph description in dot format for
 132                 further processing with the GraphViz
 133                 <citerefentry><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 134                 tool. Use a command line like <command>systemd-analyze
 135                 dot | dot -Tsvg > systemd.svg</command> to generate a
 136                 graphical dependency tree. Unless
 137                 <option>--order</option> or <option>--require</option>
 138                 is passed, the generated graph will show both ordering
 139                 and requirement dependencies. Optional pattern
 140                 globbing style specifications
 141                 (e.g. <filename>*.target</filename>) may be given at
 142                 the end. A unit dependency is included in the graph if
 143                 any of these patterns match either the origin or
 144                 destination node.</para>
 145
 146                 <para>If no command is passed, <command>systemd-analyze
 147                 time</command> is implied.</para>
 148
 149         </refsect1>
 150
 151         <refsect1>
 152                 <title>Options</title>
 153
 154                 <para>The following options are understood:</para>
 155
 156                 <variablelist>
 157                         <varlistentry>
 158                                 <term><option>-h</option></term>
 159                                 <term><option>--help</option></term>
 160
 161                                 <listitem><para>Prints a short help
 162                                 text and exits.</para></listitem>
 163                         </varlistentry>
 164
 165                         <varlistentry>
 166                                 <term><option>--user</option></term>
 167
 168                                 <listitem><para>Shows performance data
 169                                 of user sessions instead of the system
 170                                 manager.</para></listitem>
 171                         </varlistentry>
 172
 173                         <varlistentry>
 174                                 <term><option>--order</option></term>
 175                                 <term><option>--require</option></term>
 176
 177                                 <listitem><para>When used in
 178                                 conjunction with the
 179                                 <command>dot</command> command (see
 180                                 above), selects which dependencies are
 181                                 shown in the dependency graph. If
 182                                 <option>--order</option> is passed
 183                                 only dependencies of type
 184                                 <varname>After=</varname> or
 185                                 <varname>Before=</varname> are
 186                                 shown. If <option>--require</option>
 187                                 is passed only dependencies of type
 188                                 <varname>Requires=</varname>,
 189                                 <varname>RequiresOverridable=</varname>,
 190                                 <varname>Requisite=</varname>,
 191                                 <varname>RequisiteOverridable=</varname>,
 192                                 <varname>Wants=</varname> and
 193                                 <varname>Conflicts=</varname> are
 194                                 shown. If neither is passed, this shows
 195                                 dependencies of all these
 196                                 types.</para></listitem>
 197                         </varlistentry>
 198
 199                         <varlistentry>
 200                                 <term><option>--from-pattern=</option></term>
 201                                 <term><option>--to-pattern=</option></term>
 202
 203                                 <listitem><para>When used in
 204                                 conjunction with the
 205                                 <command>dot</command> command (see
 206                                 above), this selects which relationships
 207                                 are shown in the dependency graph.
 208                                 They both require
 209                                 <citerefentry><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 210                                 patterns as arguments, which are
 211                                 matched against left-hand and
 212                                 right-hand, respectively, nodes of a
 213                                 relationship. Each of these can be
 214                                 used more than once, which means a
 215                                 unit name must match one of the given
 216                                 values.</para></listitem>
 217                         </varlistentry>
 218
 219                         <varlistentry>
 220                                 <term><option>--fuzz=</option><replaceable>timespan</replaceable></term>
 221
 222                                 <listitem><para>When used in conjunction
 223                                 with the <command>critical-chain</command>
 224                                 command (see above), also show units, which
 225                                 finished <replaceable>timespan</replaceable> earlier, than the
 226                                 latest unit in the same level. The unit of
 227                                 <replaceable>timespan</replaceable> is seconds
 228                                 unless specified with a different unit,
 229                                 e.g. "50ms".</para></listitem>
 230                         </varlistentry>
 231                 </variablelist>
 232
 233         </refsect1>
 234
 235         <refsect1>
 236                 <title>Exit status</title>
 237
 238                 <para>On success 0 is returned, a non-zero failure
 239                 code otherwise.</para>
 240         </refsect1>
 241
 242         <refsect1>
 243                 <title>Examples</title>
 244
 245                 <para>This plots all dependencies of any unit whose
 246                 name starts with <literal>avahi-daemon.</literal>:</para>
 247
 248                 <programlisting>$ systemd-analyze dot 'avahi-daemon.*' | dot -Tsvg > avahi.svg
 249 $ eog avahi.svg</programlisting>
 250
 251                 <para>This plots the dependencies between all known target units:</para>
 252
 253                 <programlisting>systemd-analyze dot --to-pattern='*.target' --from-patter='*.target' | dot -Tsvg > targets.svg
 254 $ eog targets.svg</programlisting>
 255
 256
 257         </refsect1>
 258
 259         <refsect1>
 260                 <title>See Also</title>
 261                 <para>
 262                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 263                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 264                 </para>
 265         </refsect1>
 266
 267 </refentry>