chiark / gitweb /
udev: do not allow to change the DEVPATH of a device
[elogind.git] / man / systemd-cgtop.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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8   Copyright 2012 Lennart Poettering
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23
24 <refentry id="systemd-cgtop">
25
26         <refentryinfo>
27                 <title>systemd-cgtop</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-cgtop</refentrytitle>
42                 <manvolnum>1</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd-cgtop</refname>
47                 <refpurpose>Show top control groups by their resource usage</refpurpose>
48         </refnamediv>
49
50         <refsynopsisdiv>
51                 <cmdsynopsis>
52                         <command>systemd-cgtop</command>
53                         <arg choice="opt" rep="repeat">OPTIONS</arg>
54                 </cmdsynopsis>
55         </refsynopsisdiv>
56
57         <refsect1>
58                 <title>Description</title>
59
60                 <para><command>systemd-cgtop</command> shows the top
61                 control groups of the local Linux control group
62                 hierarchy, ordered by their CPU, memory, or disk I/O load. The
63                 display is refreshed in regular intervals (by default
64                 every 1s), similar in style to
65                 <citerefentry><refentrytitle>top</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
66                 If <command>systemd-cgtop</command> is not connected
67                 to a tty, only one iteration is performed and no
68                 columns headers are printed. This mode is suitable for
69                 scripting.</para>
70
71                 <para>Resource usage is only accounted for control
72                 groups in the relevant hierarchy, i.e. CPU usage is
73                 only accounted for control groups in the
74                 <literal>cpuacct</literal> hierarchy, memory usage
75                 only for those in <literal>memory</literal> and disk
76                 I/O usage for those in <literal>blkio</literal>. If
77                 resource monitoring for these resources is required,
78                 it is recommended to add the
79                 <varname>CPUAccounting=1</varname>,
80                 <varname>MemoryAccounting=1</varname> and
81                 <varname>BlockIOAccounting=1</varname> settings in the
82                 unit files in question. See
83                 <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
84                 for details.</para>
85
86                 <para>To emphasize this: unless
87                 <literal>CPUAccounting=1</literal>,
88                 <literal>MemoryAccounting=1</literal> and
89                 <literal>BlockIOAccounting=1</literal> are enabled for
90                 the services in question, no resource accounting will
91                 be available for system services and the data shown by
92                 <command>systemd-cgtop</command> will be
93                 incomplete.</para>
94         </refsect1>
95
96         <refsect1>
97                 <title>Options</title>
98
99                 <para>The following options are understood:</para>
100
101                 <variablelist>
102                         <varlistentry>
103                                 <term><option>-h</option></term>
104                                 <term><option>--help</option></term>
105
106                                 <listitem><para>Prints a short help
107                                 text and exits.</para></listitem>
108                         </varlistentry>
109
110                         <varlistentry>
111                                 <term><option>--version</option></term>
112
113                                 <listitem><para>Prints a version string and
114                                 exits.</para></listitem>
115                         </varlistentry>
116
117                         <varlistentry>
118                                 <term><option>-p</option></term>
119
120                                 <listitem><para>Order by control group
121                                 path name.</para></listitem>
122                         </varlistentry>
123
124                         <varlistentry>
125                                 <term><option>-t</option></term>
126
127                                 <listitem><para>Order by number of
128                                 tasks in control
129                                 group (i.e. threads and processes).</para></listitem>
130                         </varlistentry>
131
132                         <varlistentry>
133                                 <term><option>-c</option></term>
134
135                                 <listitem><para>Order by CPU load.</para></listitem>
136                         </varlistentry>
137
138                         <varlistentry>
139                                 <term><option>-m</option></term>
140
141                                 <listitem><para>Order by memory usage.</para></listitem>
142                         </varlistentry>
143
144                         <varlistentry>
145                                 <term><option>-i</option></term>
146
147                                 <listitem><para>Order by disk I/O load.</para></listitem>
148                         </varlistentry>
149
150                         <varlistentry>
151                                 <term><option>-b</option></term>
152                                 <term><option>--batch</option></term>
153
154                                 <listitem><para>Run in "batch" mode:
155                                 do not accept input and run until the
156                                 iteration limit set with
157                                 <option>--iterations</option> is
158                                 exhausted or until killed. This mode
159                                 could be useful for sending output
160                                 from <command>systemd-cgtop</command>
161                                 to other programs or to a
162                                 file.</para></listitem>
163                         </varlistentry>
164
165                         <varlistentry>
166                                 <term><option>-n</option></term>
167                                 <term><option>--iterations=</option></term>
168
169                                 <listitem><para>Perform only this many
170                                 iterations.</para></listitem>
171                         </varlistentry>
172
173                         <varlistentry>
174                                 <term><option>-d</option></term>
175                                 <term><option>--delay=</option></term>
176
177                                 <listitem><para>Specify refresh delay
178                                 in seconds (or if one of
179                                 <literal>ms</literal>,
180                                 <literal>us</literal>,
181                                 <literal>min</literal> is specified as
182                                 unit in this time
183                                 unit).</para></listitem>
184                         </varlistentry>
185
186                         <varlistentry>
187                                 <term><option>--depth=</option></term>
188
189                                 <listitem><para>Maximum control group
190                                 tree traversal depth. Specifies how
191                                 deep <command>systemd-cgtop</command>
192                                 shall traverse the control group
193                                 hierarchies. If 0 is specified, only
194                                 the root group is monitored. For 1,
195                                 only the first level of control groups
196                                 is monitored, and so on. Defaults to
197                                 3.</para></listitem>
198                         </varlistentry>
199
200                 </variablelist>
201
202         </refsect1>
203
204
205         <refsect1>
206                 <title>Keys</title>
207
208                 <para><command>systemd-cgtop</command> is an
209                 interactive tool and may be controlled via user input
210                 using the following keys:</para>
211
212                 <variablelist>
213                         <varlistentry>
214                                 <term>h</term>
215
216                                 <listitem><para>Shows a short help text.</para></listitem>
217                         </varlistentry>
218
219                         <varlistentry>
220                                 <term>SPACE</term>
221
222                                 <listitem><para>Immediately refresh output.</para></listitem>
223                         </varlistentry>
224
225                         <varlistentry>
226                                 <term>q</term>
227
228                                 <listitem><para>Terminate the program.</para></listitem>
229                         </varlistentry>
230
231
232                         <varlistentry>
233                                 <term>p</term>
234                                 <term>t</term>
235                                 <term>c</term>
236                                 <term>m</term>
237                                 <term>i</term>
238
239                                 <listitem><para>Sort the control groups
240                                 by path, number of tasks, CPU load,
241                                 memory usage, or IO
242                                 load, respectively.</para></listitem>
243                         </varlistentry>
244
245                         <varlistentry>
246                                 <term>%</term>
247
248                                 <listitem><para>Toggle between showing CPU time as
249                                 time or percentage.</para></listitem>
250                         </varlistentry>
251
252                         <varlistentry>
253                                 <term>+</term>
254                                 <term>-</term>
255
256                                 <listitem><para>Increase
257                                 or decrease refresh
258                                 delay, respectively.</para></listitem>
259                         </varlistentry>
260
261                 </variablelist>
262         </refsect1>
263
264         <refsect1>
265                 <title>Exit status</title>
266
267                 <para>On success 0 is returned, a non-zero failure
268                 code otherwise.</para>
269         </refsect1>
270
271         <refsect1>
272                 <title>See Also</title>
273                 <para>
274                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
275                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
276                         <citerefentry><refentrytitle>systemd-cgls</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
277                         <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
278                         <citerefentry><refentrytitle>top</refentrytitle><manvolnum>1</manvolnum></citerefentry>
279                 </para>
280         </refsect1>
281
282 </refentry>