.TH "LTTNG" "1" "May 13th, 2014" "" ""
.SH "NAME"
-lttng \(em LTTng 2.x tracer control command line tool
+lttng \- LTTng 2.x tracer control command line tool
.SH "SYNOPSIS"
those traces is done using the babeltrace(1) text viewer.
We introduce the notion of \fBtracing domains\fP which is essentially a type of
-tracer (kernel, user space or JUL for now). In the future, we could see more
-tracer like for instance an hypervisor. For some commands, you'll need to
-specify on which domain the command operates (\-u, \-k or \-j). For instance,
-the kernel domain must be specified when enabling a kernel event.
+tracer (kernel, user space, JUL, LOG4J or Python for now). In the future, we
+could see more tracer like for instance an hypervisor. For some commands,
+you'll need to specify on which domain the command operates (\-u, \-k, \-l, \-j
+or \-p). For instance, the kernel domain must be specified when enabling a
+kernel event.
In order to trace the kernel, the session daemon needs to be running as root.
LTTng provides the use of a \fBtracing group\fP (default: tracing). Whomever is
.SH "OPTIONS"
.PP
-This program follow the usual GNU command line syntax with long options starting with
+This program follows the usual GNU command line syntax with long options starting with
two dashes. Below is a summary of the available options.
.PP
.BR "\-h, \-\-help"
Show summary of possible options and commands.
.TP
+.BR "\-V, \-\-version"
+Show version.
+.TP
.BR "\-v, \-\-verbose"
Increase verbosity.
Three levels of verbosity are available which are triggered by putting additional v to
.TP
.BR "\-\-list\-commands"
Simple listing of lttng commands.
+.TP
+.BR "\-m, \-\-mi TYPE
+Machine interface
+
+TYPE supported: XML
+
+Machine interface (MI) mode converts the traditional pretty printing to a
+machine output syntax. MI mode provides a format change-resistant way to access
+information generated via the lttng command line.
+
+When using MI mode, the data is printed on \fBstdout\fP. Error and warning are
+printed on \fBstderr\fP with the pretty print default format.
+
+If any errors occur during the execution of a command, the return value of the
+command will be different than zero. In this case, lttng does NOT guarantee the
+syntax and data validity of the generated MI output.
+
+For XML output type, a schema definition (XSD) file used for validation can be
+found under src/common/mi_lttng.xsd
+
.SH "COMMANDS"
.PP
in overwrite mode and with mmap output (splice not supported).
.TP
.BR "\-\-live [USEC]"
-Set the session exclusively in live mode. The paremeter is the delay in micro
+Set the session exclusively in live mode. The parameter is the delay in micro
seconds before the data is flushed and streamed. The live mode allows you to
stream the trace and view it while it's being recorded by any tracer. For that,
you need a lttng-relayd and this session requires a network URL (\-U or
After the start, you'll be able to read the events while they are being
recorded in /tmp/lttng.
+.TP
+.BR "\-\-shm-path PATH"
+
+Path where shared memory holding buffers should be created. Useful
+when used with PRAMFS or other persistent memory filesystems to extract
+trace data in the event of a crash requiring a reboot.
+
+See the \fBlttng-crash(1)\fP utility for more information on crash recovery.
+
.TP
.BR "\-U, \-\-set-url=URL"
Set URL for the consumer output destination. It is persistent for the
Maximum size of each tracefile within a stream (in bytes).
0 means unlimited. (default: 0)
Note: traces generated with this option may inaccurately report
-discarded events as per CTF 1.8.
+discarded events as of CTF 1.8.
.TP
.BR "\-W, \-\-tracefile-count COUNT"
Used in conjunction with \-C option, this will limit the number of files
.BR "\-j, \-\-jul"
Apply for Java application using Java Util Logging interface (JUL)
.TP
+.BR "\-l, \-\-log4j"
+Apply for Java application using LOG4J
+.TP
+.BR "\-p, \-\-python"
+Apply for Python application using the logging module.
+.TP
.BR "\-\-tracepoint"
Tracepoint event (default). Userspace tracer supports wildcards at the end
of string. Don't forget to quote to deal with bash expansion.
Tracepoint loglevel range from 0 to loglevel. Listed in the help (\-h).
For the JUL domain, the loglevel ranges are detailed with the \-\-help
option thus starting from SEVERE to FINEST.
+For the LOG4J domain, loglevels range from FATAL to TRACE which are also
+detailed in the help.
+For the Python domain, loglevels range from CRITICAL to DEBUG which are
+detailed in the help as well.
.TP
.BR "\-\-loglevel-only NAME"
Tracepoint loglevel (only this loglevel).
Specifying a filter is only allowed when enabling events within a session before
tracing is started. If the filter fails to link with the event
within the traced domain, the event will be discarded.
-Filtering is currently only implemented for the user-space tracer.
Expression examples:
.TP
.BR "\-j, \-\-jul"
Apply for Java application using Java Util Logging interface (JUL)
+.TP
+.BR "\-l, \-\-log4j"
+Apply for Java application using LOG4J
+.TP
+.BR "\-p, \-\-python"
+Apply for Python application using the logging module.
.RE
.PP
calls events).
With \-j alone, the available JUL event from registered application will be
list. The event corresponds to the Logger name in the Java JUL application.
+With \-l alone, the available LOG4J event from registered application will be
+list. The event corresponds to the Logger name in the Java LOG4J application.
+With \-p alone, the available Python event from registered application will be
+list. The event corresponds to the Logger name in the Python application.
With \-u alone, it will list all available user-space events from registered
applications. Here is an example of 'lttng list \-u':
.BR "\-j, \-\-jul"
Apply for Java application using JUL
.TP
+.BR "\-l, \-\-log4j"
+Apply for Java application using LOG4J
+.TP
+.BR "\-p, \-\-python"
+Apply for Python application using the logging module.
+.TP
.BR "\-f, \-\-fields"
List event fields
Load tracing session configuration
If NAME is omitted, all session configurations found in both the user's session
-configuration directory and the system session configuration directory will be
-loaded.
+configuration directory (default: ~/.lttng/sessions/) and the system session
+configuration directory (default: /etc/lttng/sessions/) will be loaded. Note
+that the sessions in the user directory are loaded first and then the system
+wide directory are loaded.
.B OPTIONS:
Load all session configurations (default).
.TP
.BR "\-i, \-\-input-path PATH"
-Specify the input path for session configurations.
+Specify the input path for session configurations. This overrides the default
+session configuration directory.
.TP
.BR "\-f, -\-force"
Overwrite current session configuration(s) if a session of the same name
Save tracing session configuration
If SESSION is omitted, all session configurations will be saved to individual
-\fB.lttng\fP files under the user's session configuration directory. The
-default session configuration file naming scheme is \fBSESSION.lttng\fP.
+\fB.lttng\fP files under the user's session configuration directory (default:
+~/.lttng/sessions/). The default session configuration file naming scheme is
+\fBSESSION.lttng\fP.
+
+For instance, a user in the tracing group saving a session from a root session
+daemon will save it in her/his user directory.
.B OPTIONS:
Save all session configurations (default).
.TP
.BR "\-o, \-\-output-path PATH"
-Specify the output path for saved sessions (default: ~/.lttng/sessions/).
+Specify the output path for saved sessions. This overrides the default session
+configuration directory.
.TP
.BR "\-f, -\-force"
Overwrite session configuration file if session name clashes.
.TP
\fBadd-output\fP [-m <SIZE>] [-s <NAME>] [-n <NAME>] <URL> | -C <URL> -D <URL>
-Setup and add an snapshot output for a session. Output are the destination
+Setup and add a snapshot output for a session. Output is the destination
where the snapshot will be sent. Only one output is permitted. To change it,
you'll need to delete it and add back the new one.
.TP
\fBdel-output\fP ID | NAME [-s <NAME>]
-Delete an output for a session using the ID. You can either specify the
-output's ID that can be found with list-output or the name.
+Delete an output for a session using the output's ID. You can either specify the
+output by name or use its ID as returned by the list-output command.
.TP
\fBlist-output\fP [-s <NAME>]
Name of the snapshot's output.
.TP
.BR "\-m, \-\-max-size SIZE"
-Maximum size in bytes of the snapshot. The maxium size does not include the
+Maximum size in bytes of the snapshot. The maximum size does not include the
metadata file. Human readable format is accepted: {+k,+M,+G}. For instance,
\-\-max-size 5M
.TP
.RE
.PP
-.SH "JUL DOMAIN"
-This section explains the JUL domain (\-j, \-\-jul) where JUL stands for Java
-Util Logging. You can use that feature by using the \fBliblttng-ust-jul.so\fP
-from the lttng-ust(3) project.
+.SH "JUL/LOG4J DOMAIN"
+
+This section explains the JUL and LOG4J domain where JUL stands for Java Util
+Logging. You can use these by using the \fBliblttng-ust-<domain>-jni.so\fP from
+the lttng-ust(3) project.
The LTTng Java Agent uses JNI to link the UST tracer to the Java application
that uses the agent. Thus, it behaves similarly to the UST domain (\-u). When
-enabling events with the JUL domain, you enable a Logger name that will then be
-mapped to a default UST tracepoint called \fBlttng_jul:jul_event\fP in the
-\fBlttng_jul_channel\fP. Using the lttng-ctl API, any JUL events must use the
-tracepoint event type (same as \-\-tracepoint).
+enabling events, you enable a Logger name that will then be mapped to a default
+UST tracepoint called \fBlttng_jul:<domain>_event\fP in the
+\fBlttng_<domain>_channel\fP. Using the lttng-ctl API, any JUL/LOG4J events
+must use the tracepoint event type (same as \-\-tracepoint).
-Because of the default immutable channel (\fBlttng_jul_channel\fP), the
-\fBenable-channel\fP command CAN NOT be used with the JUL domain thus not
-having any \-j option.
+Because of the default immutable channel, the \fBenable-channel\fP command CAN
+NOT be used with the JUL and LOG4J domain thus not having any options.
-For JUL event, loglevels are supported with the JUL ABI values. Use \fBlttng
-enable-event \-h\fP to list them. Wildcards are NOT supported except the "*"
-meaning all events (same as \-a).
+Also, loglevels are supported. Use \fBlttng enable-event \-h\fP to list them.
+Wildcards are NOT supported except the "*" meaning all events (same as \-a).
Exactly like the UST domain, if the Java application has the same UID as you,
you can trace it. Same goes for the tracing group accessing root applications.
-Finally, you can list every Logger name that are available from JUL registered
-applications to the session daemon by using \fBlttng list \-j\fP.
+Finally, you can list every Logger name that are available from registered
+applications to the session daemon by using \fBlttng list \-j\fP or \fB\-l\fP.
-Here is an example on how to use this domain.
+Here is an example on how to use the JUL domain.
.nf
$ lttng list -j
.BR lttng-ust(3),
.BR lttng-sessiond(8),
.BR lttng-relayd(8),
+.BR lttng-crash(1),
.SH "BUGS"
.PP
If you encounter any issues or usability problem, please report it on our
mailing list <lttng-dev@lists.lttng.org> to help improve this project or
-at https://bugs.lttng.org which is a bugtracker.
+at https://bugs.lttng.org which is a bug tracker.
.PP
.SH "CREDITS"
.PP
lttng-tools was originally written by Mathieu Desnoyers, Julien Desfossez and
David Goulet. More people have since contributed to it. It is currently
-maintained by David Goulet <dgoulet@efficios.com>.
+maintained by Jérémie Galarneau <jeremie.galarneau@efficios.com>.
.PP
projects / lttng-tools.git / blobdiff