man/systemd-bootchart.xml

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   3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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   6 <!--
   7   This file is part of systemd.
   8
   9   Copyright 2012 Intel Corporation
  10
  11   Authors:
  12     Auke Kok <auke-jan.h.kok@intel.com>
  13     William Giokas <1007380@gmail.com>
  14
  15   systemd is free software; you can redistribute it and/or modify it
  16   under the terms of the GNU Lesser General Public License as published by
  17   the Free Software Foundation; either version 2.1 of the License, or
  18   (at your option) any later version.
  19
  20   systemd is distributed in the hope that it will be useful, but
  21   WITHOUT ANY WARRANTY; without even the implied warranty of
  22   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  23   Lesser General Public License for more details.
  24
  25   You should have received a copy of the GNU Lesser General Public License
  26   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  27 -->
  28
  29 <refentry id="systemd-bootchart" conditional='ENABLE_BOOTCHART'
  30           xmlns:xi="http://www.w3.org/2001/XInclude">
  31
  32         <refentryinfo>
  33                 <title>systemd-bootchart</title>
  34                 <productname>systemd</productname>
  35
  36                 <authorgroup>
  37                         <author>
  38                                 <contrib>Developer</contrib>
  39                                 <firstname>Auke</firstname>
  40                                 <surname>Kok</surname>
  41                                 <email>auke-jan.h.kok@intel.com</email>
  42                         </author>
  43                 </authorgroup>
  44         </refentryinfo>
  45
  46         <refmeta>
  47                 <refentrytitle>systemd-bootchart</refentrytitle>
  48                 <manvolnum>1</manvolnum>
  49         </refmeta>
  50
  51         <refnamediv>
  52                 <refname>systemd-bootchart</refname>
  53                 <refpurpose>Boot performance graphing tool</refpurpose>
  54         </refnamediv>
  55
  56         <refsect1>
  57                 <title>Description</title>
  58                 <para>
  59                         <command>systemd-bootchart</command> is a
  60                         tool, usually run at system startup, that
  61                         collects the CPU load, disk load, memory
  62                         usage, as well as per-process information from
  63                         a running system. Collected results are output
  64                         as an SVG graph. Normally, systemd-bootchart
  65                         is invoked by the kernel by passing
  66                         <option>init=<filename>/usr/lib/systemd/systemd-bootchart</filename></option>
  67                         on the kernel commandline. systemd-bootchart will then
  68                         fork the real init off to resume normal system
  69                         startup, while monitoring and logging startup
  70                         information in the background.
  71                 </para>
  72                 <para>
  73                         After collecting a certain amount of data
  74                         (usually 15-30 seconds, default 20 s) the
  75                         logging stops and a graph is generated from
  76                         the logged information. This graph contains
  77                         vital clues as to which resources are being used,
  78                         in which order, and where possible problems
  79                         exist in the startup sequence of the system.
  80                         It is essentially a more detailed version of
  81                         the <command>systemd-analyze plot</command>
  82                         function.
  83                 </para>
  84                 <para>
  85                         Of course, bootchart can also be used at any
  86                         moment in time to collect and graph some data
  87                         for an amount of time. It is
  88                         recommended to use the <option>--rel</option>
  89                         switch in this case.
  90                 </para>
  91                 <para>
  92                         Bootchart does not require root privileges,
  93                         and will happily run as a normal user.
  94                 </para>
  95                 <para>
  96                         Bootchart graphs are by default written
  97                         time-stamped in <filename>/run/log</filename>
  98                         and saved to the journal with
  99                         <varname>MESSAGE_ID=9f26aa562cf440c2b16c773d0479b518</varname>.
 100                         Journal field <varname>BOOTCHART=</varname> contains
 101                         the bootchart in SVG format.
 102                 </para>
 103
 104         </refsect1>
 105
 106         <refsect1>
 107                 <title>Invocation</title>
 108
 109                 <para><command>systemd-bootchart</command> can be invoked in several different ways:</para>
 110
 111                 <variablelist>
 112
 113                         <varlistentry>
 114                                 <term><emphasis>Kernel invocation</emphasis></term>
 115                                 <listitem><para>The kernel can invoke
 116                                 <command>systemd-bootchart</command>
 117                                 instead of the init process. In turn,
 118                                 <command>systemd-bootchart</command>
 119                                 will invoke <command>/sbin/init</command>.
 120                                 </para></listitem>
 121                         </varlistentry>
 122
 123                         <varlistentry>
 124                                 <term><emphasis>Started as a standalone program</emphasis></term>
 125                                 <listitem><para>One can execute
 126                                 <command>systemd-bootchart</command>
 127                                 as normal application from the
 128                                 commandline. In this mode it is highly
 129                                 recommended to pass the
 130                                 <option>-r</option> flag in order to
 131                                 not graph the time elapsed since boot
 132                                 and before systemd-bootchart was
 133                                 started, as it may result in extremely
 134                                 large graphs.  </para></listitem>
 135                         </varlistentry>
 136                 </variablelist>
 137         </refsect1>
 138
 139         <refsect1>
 140                 <title>Options</title>
 141
 142                 <para>These options can also be set in the
 143                 <filename>/etc/systemd/bootchart.conf</filename>
 144                 file. See
 145                 <citerefentry><refentrytitle>bootchart.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
 146                 </para>
 147
 148                 <variablelist>
 149                         <xi:include href="standard-options.xml" xpointer="help" />
 150
 151                         <varlistentry>
 152                                 <term><option>-n</option></term>
 153                                 <term><option>--sample <replaceable>N</replaceable></option></term>
 154                                 <listitem><para>Specify the number of
 155                                 samples, <replaceable>N</replaceable>,
 156                                 to record. Samples will be recorded at
 157                                 intervals defined with <option>--freq</option>.
 158                                 </para></listitem>
 159                         </varlistentry>
 160
 161                         <varlistentry>
 162                                 <term><option>-f</option></term>
 163                                 <term><option>--freq <replaceable>f</replaceable></option></term>
 164                                 <listitem><para>Specify the sample log
 165                                 frequency, a positive real <replaceable>f</replaceable>, in Hz.
 166                                 Most systems can cope with values up to 25-50 without
 167                                 creating too much overhead.</para></listitem>
 168                         </varlistentry>
 169
 170                         <varlistentry>
 171                                 <term><option>-r</option></term>
 172                                 <term><option>--rel</option></term>
 173                                 <listitem><para>Use relative times instead of absolute
 174                                 times. This is useful for using bootchart at post-boot
 175                                 time to profile an already booted system. Without this
 176                                 option the graph would become extremely large. If set, the
 177                                 horizontal axis starts at the first recorded sample
 178                                 instead of time 0.0.</para></listitem>
 179                         </varlistentry>
 180
 181                         <varlistentry>
 182                                 <term><option>-F</option></term>
 183                                 <term><option>--no-filter</option></term>
 184                                 <listitem><para>Disable filtering of tasks that
 185                                 did not contribute significantly to the boot. Processes
 186                                 that are too short-lived (only seen in one sample) or
 187                                 that do not consume any significant CPU time (less than
 188                                 0.001 s) will not be displayed in the output graph.
 189                                 </para></listitem>
 190                         </varlistentry>
 191
 192                         <varlistentry>
 193                                 <term><option>-C</option></term>
 194                                 <term><option>--cmdline</option></term>
 195                                 <listitem><para>Display the full command line with arguments of processes,
 196                                 instead of only the process name.
 197                                 </para></listitem>
 198                         </varlistentry>
 199
 200                         <varlistentry>
 201                                 <term><option>-o</option></term>
 202                                 <term><option>--output <replaceable>path</replaceable></option></term>
 203                                 <listitem><para>Specify the output directory for the
 204                                 graphs. By default, bootchart writes the graphs to
 205                                 <filename>/run/log</filename>.</para></listitem>
 206                         </varlistentry>
 207
 208                         <varlistentry>
 209                                 <term><option>-i</option></term>
 210                                 <term><option>--init <replaceable>path</replaceable></option></term>
 211                                 <listitem><para>Use this init binary. Defaults to
 212                                 <command>/sbin/init</command>.
 213                                 </para></listitem>
 214                         </varlistentry>
 215
 216                         <varlistentry>
 217                                 <term><option>-p</option></term>
 218                                 <term><option>--pss</option></term>
 219                                 <listitem><para>Enable logging and graphing
 220                                 of processes' PSS (Proportional Set Size)
 221                                 memory consumption. See <filename>filesystems/proc.txt</filename>
 222                                 in the kernel documentation for an
 223                                 explanation of this field.
 224                                 </para></listitem>
 225                         </varlistentry>
 226
 227                         <varlistentry>
 228                                 <term><option>-e</option></term>
 229                                 <term><option>--entropy</option></term>
 230                                 <listitem><para>Enable logging and graphing
 231                                 of the kernel random entropy pool size.</para></listitem>
 232                         </varlistentry>
 233
 234                         <varlistentry>
 235                                 <term><option>-x</option></term>
 236                                 <term><option>--scale-x <replaceable>N</replaceable></option></term>
 237                                 <listitem><para>Horizontal scaling factor for all variable
 238                                 graph components.</para></listitem>
 239                         </varlistentry>
 240
 241                         <varlistentry>
 242                                 <term><option>-y</option></term>
 243                                 <term><option>--scale-y <replaceable>N</replaceable></option></term>
 244                                 <listitem><para>Vertical scaling factor for all variable
 245                                 graph components.</para></listitem>
 246                         </varlistentry>
 247
 248                 </variablelist>
 249
 250
 251         </refsect1>
 252
 253         <refsect1>
 254                 <title>Output</title>
 255
 256                 <para><command>systemd-bootchart</command> generates SVG graphs. In order to render those
 257                 on a graphical display any SVG capable viewer can be used. It should be
 258                 noted that the SVG render engines in most browsers (including Chrome
 259                 and Firefox) are many times faster than dedicated graphical applications
 260                 like Gimp and Inkscape.  Just point your browser at <ulink url="file:///run/log/" />!
 261                 </para>
 262         </refsect1>
 263
 264         <refsect1>
 265                 <title>History</title>
 266
 267                 <para>This version of bootchart was implemented from
 268                 scratch, but is inspired by former bootchart
 269                 incantations:</para>
 270
 271                 <variablelist>
 272                         <varlistentry>
 273                                 <term><emphasis>Original bash</emphasis></term>
 274                                 <listitem><para>The original bash/shell code implemented
 275                                 bootchart. This version created a compressed tarball for
 276                                 processing with external applications. This version did
 277                                 not graph anything, only generated data.</para></listitem>
 278                         </varlistentry>
 279
 280                         <varlistentry>
 281                                 <term><emphasis>Ubuntu C Implementation</emphasis></term>
 282                                 <listitem><para>This version replaced the shell version with
 283                                 a fast and efficient data logger, but also did not graph
 284                                 the data.</para></listitem>
 285                         </varlistentry>
 286
 287                         <varlistentry>
 288                                 <term><emphasis>Java bootchart</emphasis></term>
 289                                 <listitem><para>This was the original graphing application
 290                                 for charting the data, written in java.</para></listitem>
 291                         </varlistentry>
 292
 293                         <varlistentry>
 294                                 <term><emphasis>pybootchartgui.py</emphasis></term>
 295                                 <listitem><para>pybootchart created a graph from the data
 296                                 collected by either the bash or C version.</para></listitem>
 297                         </varlistentry>
 298                 </variablelist>
 299
 300                 <para>The version of bootchart you are using now combines both the data
 301                 collection and the charting into a single application, making it more
 302                 efficient and simpler. There are no longer any timing issues with the data
 303                 collector and the grapher, as the graphing cannot be run until the data
 304                 has been collected. Also, the data kept in memory is reduced to the absolute
 305                 minimum needed.</para>
 306
 307         </refsect1>
 308
 309         <refsect1>
 310                 <title>See Also</title>
 311                 <para>
 312                         <citerefentry><refentrytitle>bootchart.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 313                 </para>
 314         </refsect1>
 315
 316         <refsect1>
 317                 <title>Bugs</title>
 318                 <para>systemd-bootchart does not get the model information for the hard drive
 319                 unless the root device is specified with <code>root=/dev/sdxY</code>. Using
 320                 UUIDs or PARTUUIDs will boot fine, but the hard drive model will not be
 321                 added to the chart.</para>
 322                 <para>For bugs, please contact the author and current maintainer:</para>
 323                 <simplelist>
 324                         <member>Auke Kok <email>auke-jan.h.kok@intel.com</email></member>
 325                 </simplelist>
 326         </refsect1>
 327
 328 </refentry>