chiark / gitweb /
update TODO
[elogind.git] / man / systemd-bootchart.xml
index a3fea05b5c0b8e84aff7e62aa8b3fd362d24e186..0068e928a53489f98820fe55225888c8d4a35604 100644 (file)
@@ -26,7 +26,9 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 -->
 
-<refentry id="systemd-bootchart" conditional='ENABLE_BOOTCHART'>
+<refentry id="systemd-bootchart" conditional='ENABLE_BOOTCHART'
+          xmlns:xi="http://www.w3.org/2001/XInclude">
+
         <refentryinfo>
                 <title>systemd-bootchart</title>
                 <productname>systemd</productname>
 
         <refnamediv>
                 <refname>systemd-bootchart</refname>
-                <refpurpose>Boot performance analysis graphing tool</refpurpose>
+                <refpurpose>Boot performance graphing tool</refpurpose>
         </refnamediv>
 
         <refsect1>
                 <title>Description</title>
-
-                <para>Systemd-bootchart is an boot time analysis tool. It represents
-                various aspects of the system as graph elements. These graph
-                elements allow the user to determine resource usage, efficiency
-                and performance issues.</para>
+                <para>
+                        <command>systemd-bootchart</command> is a
+                        tool, usually run at system startup, that
+                        collects the CPU load, disk load, memory
+                        usage, as well as per-process information from
+                        a running system. Collected results are output
+                        as an SVG graph. Normally, systemd-bootchart
+                        is invoked by the kernel by passing
+                        <option>init=<filename>/usr/lib/systemd/systemd-bootchart</filename></option>
+                        on the kernel command line. systemd-bootchart will then
+                        fork the real init off to resume normal system
+                        startup, while monitoring and logging startup
+                        information in the background.
+                </para>
+                <para>
+                        After collecting a certain amount of data
+                        (usually 15-30 seconds, default 20 s) the
+                        logging stops and a graph is generated from
+                        the logged information. This graph contains
+                        vital clues as to which resources are being used,
+                        in which order, and where possible problems
+                        exist in the startup sequence of the system.
+                        It is essentially a more detailed version of
+                        the <command>systemd-analyze plot</command>
+                        function.
+                </para>
+                <para>
+                        Of course, bootchart can also be used at any
+                        moment in time to collect and graph some data
+                        for an amount of time. It is
+                        recommended to use the <option>--rel</option>
+                        switch in this case.
+                </para>
+                <para>
+                        Bootchart does not require root privileges,
+                        and will happily run as a normal user.
+                </para>
+                <para>
+                        Bootchart graphs are by default written
+                        time-stamped in <filename>/run/log</filename>
+                        and saved to the journal with
+                        <varname>MESSAGE_ID=9f26aa562cf440c2b16c773d0479b518</varname>.
+                        Journal field <varname>BOOTCHART=</varname> contains
+                        the bootchart in SVG format.
+                </para>
 
         </refsect1>
 
         <refsect1>
                 <title>Invocation</title>
 
-                <para>systemd-bootchart can be invoked in several different ways:</para>
+                <para><command>systemd-bootchart</command> can be invoked in several different ways:</para>
 
                 <variablelist>
 
                         <varlistentry>
-                                <title>Kernel invocation</title>
-                                <listitem><para>The kernel can invoke systemd-bootchart
-                                instead of the init process. In itself, systemd-bootchart
-                                will invoke <filename>/sbin/init</filename> if invoked in
-                                this matter.</para></listitem>
+                                <term><emphasis>Kernel invocation</emphasis></term>
+                                <listitem><para>The kernel can invoke
+                                <command>systemd-bootchart</command>
+                                instead of the init process. In turn,
+                                <command>systemd-bootchart</command>
+                                will invoke <command>/sbin/init</command>.
+                                </para></listitem>
                         </varlistentry>
 
                         <varlistentry>
-                                <title>Started as a standalone program</title>
-                                <listitem><para>One can execute systemd-bootchart as
-                                normal application from the commandline. In this mode
-                                it is highly recommended to pass the "-r" flag in order
-                                to not graph the time elapsed since boot and before
-                                systemd-bootchart was started, as it may result in
-                                extremely large graphs.
-                                </para></listitem>
+                                <term><emphasis>Started as a standalone program</emphasis></term>
+                                <listitem><para>One can execute
+                                <command>systemd-bootchart</command>
+                                as normal application from the
+                                command line. In this mode it is highly
+                                recommended to pass the
+                                <option>-r</option> flag in order to
+                                not graph the time elapsed since boot
+                                and before systemd-bootchart was
+                                started, as it may result in extremely
+                                large graphs. The time elapsed since boot
+                                might also include any time that the system
+                                was suspended.</para></listitem>
                         </varlistentry>
                 </variablelist>
         </refsect1>
         <refsect1>
                 <title>Options</title>
 
-                <variablelist class='bootchart-directives'>
+                <para>These options can also be set in the
+                <filename>/etc/systemd/bootchart.conf</filename>
+                file. See
+                <citerefentry project='man-pages'><refentrytitle>bootchart.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+                </para>
+
+                <variablelist>
+                        <xi:include href="standard-options.xml" xpointer="help" />
 
                         <varlistentry>
                                 <term><option>-n</option></term>
-                                <term><option>--sample N</option></term>
-                                <listitem><para>Specify the amount of samples to
-                                record total before bootchart exits. Each sample will
-                                record at intervals defined by --freq.</para></listitem>
+                                <term><option>--sample <replaceable>N</replaceable></option></term>
+                                <listitem><para>Specify the number of
+                                samples, <replaceable>N</replaceable>,
+                                to record. Samples will be recorded at
+                                intervals defined with <option>--freq</option>.
+                                </para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><option>-f</option></term>
-                                <term><option>--freq N</option></term>
-                                <listitem><para>Specify the sample log frequency.
-                                This can be a fractional number, but must be larger than
-                                0.0. Most systems can cope with values under 25-50 without
-                                impacting boot time severely.</para></listitem>
+                                <term><option>--freq <replaceable>f</replaceable></option></term>
+                                <listitem><para>Specify the sample log
+                                frequency, a positive real <replaceable>f</replaceable>, in Hz.
+                                Most systems can cope with values up to 25-50 without
+                                creating too much overhead.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><option>--rel</option></term>
                                 <listitem><para>Use relative times instead of absolute
                                 times. This is useful for using bootchart at post-boot
-                                time to profile an already booted system, otherwise the
-                                graph would become extremely large. If set, the
+                                time to profile an already booted system. Without this
+                                option the graph would become extremely large. If set, the
                                 horizontal axis starts at the first recorded sample
-                                instead of time=0.0.</para></listitem>
+                                instead of time 0.0.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><option>-F</option></term>
-                                <term><option>--filter</option></term>
-                                <listitem><para>Disable filtering of tasks tasks that
+                                <term><option>--no-filter</option></term>
+                                <listitem><para>Disable filtering of tasks that
                                 did not contribute significantly to the boot. Processes
                                 that are too short-lived (only seen in one sample) or
                                 that do not consume any significant CPU time (less than
-                                0.001sec) will not be displayed in the output graph.
+                                0.001 s) will not be displayed in the output graph.
+                                </para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>-C</option></term>
+                                <term><option>--cmdline</option></term>
+                                <listitem><para>Display the full command line with arguments of processes,
+                                instead of only the process name.
+                                </para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>-g</option></term>
+                                <term><option>--control-group</option></term>
+                                <listitem><para>Display process control group
                                 </para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><option>-o</option></term>
-                                <term><option>--output [path]</option></term>
-                                <listitem><para>Configures the output folder for writing
-                                the graphs. By default, bootchart writes the graphs to
+                                <term><option>--output <replaceable>path</replaceable></option></term>
+                                <listitem><para>Specify the output directory for the
+                                graphs. By default, bootchart writes the graphs to
                                 <filename>/run/log</filename>.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><option>-i</option></term>
-                                <term><option>--init [path]</option></term>
-                                <listitem><para>Set init binary to run. Defaults to
-                                <filename>/sbin/init</filename>.
+                                <term><option>--init <replaceable>path</replaceable></option></term>
+                                <listitem><para>Use this init binary. Defaults to
+                                <command>/sbin/init</command>.
                                 </para></listitem>
                         </varlistentry>
 
                                 <term><option>-p</option></term>
                                 <term><option>--pss</option></term>
                                 <listitem><para>Enable logging and graphing
-                                of processes PSS memory consumption.</para></listitem>
+                                of processes' PSS (Proportional Set Size)
+                                memory consumption. See <filename>filesystems/proc.txt</filename>
+                                in the kernel documentation for an
+                                explanation of this field.
+                                </para></listitem>
                         </varlistentry>
 
                         <varlistentry>
 
                         <varlistentry>
                                 <term><option>-x</option></term>
-                                <term><option>--scale-x N</option></term>
+                                <term><option>--scale-x <replaceable>N</replaceable></option></term>
                                 <listitem><para>Horizontal scaling factor for all variable
                                 graph components.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
                                 <term><option>-y</option></term>
-                                <term><option>--scale-y N</option></term>
+                                <term><option>--scale-y <replaceable>N</replaceable></option></term>
                                 <listitem><para>Vertical scaling factor for all variable
                                 graph components.</para></listitem>
                         </varlistentry>
         <refsect1>
                 <title>Output</title>
 
-                <para>Systemd-bootchart generates SVG graphs. In order to render these
+                <para><command>systemd-bootchart</command> generates SVG graphs. In order to render those
                 on a graphical display any SVG capable viewer can be used. It should be
                 noted that the SVG render engines in most browsers (including Chrome
                 and Firefox) are many times faster than dedicated graphical applications
-                like Gimp and Inkscape.  Just point your browser at "file:///var/log"!
+                like Gimp and Inkscape.  Just point your browser at <ulink url="file:///run/log/" />!
+                </para>
+        </refsect1>
+
+        <refsect1>
+                <title>History</title>
+
+                <para>This version of bootchart was implemented from
+                scratch, but is inspired by former bootchart
+                incantations:</para>
+
+                <variablelist>
+                        <varlistentry>
+                                <term><emphasis>Original bash</emphasis></term>
+                                <listitem><para>The original bash/shell code implemented
+                                bootchart. This version created a compressed tarball for
+                                processing with external applications. This version did
+                                not graph anything, only generated data.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><emphasis>Ubuntu C Implementation</emphasis></term>
+                                <listitem><para>This version replaced the shell version with
+                                a fast and efficient data logger, but also did not graph
+                                the data.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><emphasis>Java bootchart</emphasis></term>
+                                <listitem><para>This was the original graphing application
+                                for charting the data, written in java.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><emphasis>pybootchartgui.py</emphasis></term>
+                                <listitem><para>pybootchart created a graph from the data
+                                collected by either the bash or C version.</para></listitem>
+                        </varlistentry>
+                </variablelist>
+
+                <para>The version of bootchart you are using now combines both the data
+                collection and the charting into a single application, making it more
+                efficient and simpler. There are no longer any timing issues with the data
+                collector and the grapher, as the graphing cannot be run until the data
+                has been collected. Also, the data kept in memory is reduced to the absolute
+                minimum needed.</para>
+
+        </refsect1>
+
+        <refsect1>
+                <title>See Also</title>
+                <para>
+                        <citerefentry project='man-pages'><refentrytitle>bootchart.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                 </para>
         </refsect1>
 
         <refsect1>
-                  <title>See Also</title>
-                  <para>
-                          <citerefentry><refentrytitle>bootchart.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-                  </para>
+                <title>Bugs</title>
+                <para>systemd-bootchart does not get the model information for the hard drive
+                unless the root device is specified with <code>root=/dev/sdxY</code>. Using
+                UUIDs or PARTUUIDs will boot fine, but the hard drive model will not be
+                added to the chart.</para>
+                <para>For bugs, please contact the author and current maintainer:</para>
+                <simplelist>
+                        <member>Auke Kok <email>auke-jan.h.kok@intel.com</email></member>
+                </simplelist>
         </refsect1>
 
 </refentry>