Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
LTTNG-ADD-CONTEXT(1)		 LTTng Manual		  LTTNG-ADD-CONTEXT(1)

NAME
       lttng-add-context - Add context fields to an LTTng channel

SYNOPSIS
       Add context fields to a channel:

       lttng [GENERAL OPTIONS] add-context
	     (--kernel | --userspace | --jul | --log4j)
	     [--session=SESSION] [--channel=CHANNEL]
	     --type=TYPE [--type=TYPE]...

       List the	available context fields:

       lttng [GENERAL OPTIONS] add-context --list

DESCRIPTION
       The lttng add-context command adds one or more context fields to	a
       channel.

       Channels	are created with the lttng-enable-channel(1) command.

       When context fields are added to	a channel, all the events emitted
       within this channel contain the dynamic values of those context fields.

       If the --session	option is omitted, the current tracing session is
       used. If	the --channel option is	omitted, the context fields are	added
       to all the selected tracing session's channels.

       Many context fields can be added	to a channel at	once by	repeating the
       --type option.

       perf counters are available as per-CPU (perf:cpu: prefix) as well as
       per-thread (perf:thread:	prefix)	counters. Currently, per-CPU counters
       can only	be used	in the Linux kernel tracing domain, while per-thread
       counters	can only be used in the	user space tracing domain.

       It is also possible to enable PMU counters by raw ID using the
       perf:cpu:raw:rN:NAME (Linux kernel tracing domain) or
       perf:thread:raw:rN:NAME (user space tracing domain), with:

       N
	   A hexadecimal event descriptor which	is the same format as used by
	   perf-record(1): a concatenation of the event	number and umask value
	   provided by the processor's manufacturer. The possible values for
	   this	field are processor-specific.

       NAME
	   Custom name to easily recognize the counter.

       Application-specific context fields can be added	to a channel using the
       following syntax:

	   $app.PROVIDER:TYPE

       with:

       PROVIDER
	   Provider name.

       TYPE
	   Context type	name.

	   Note
	   Make	sure to	single-quote the type when running the command from a
	   shell, as $ is a special character for variable substitution	in
	   most	shells.

       Use the --list option without other arguments to	list the available
       context field names.

OPTIONS
       General options are described in	lttng(1).

   Domain
       One of:

       -j, --jul
	   Add context to channel in the java.util.logging (JUL) domain.

       -k, --kernel
	   Add context to channel in the Linux kernel domain.

       -l, --log4j
	   Add context to channel in the Apache	log4j domain.

       -u, --userspace
	   Add context to channel in the user space domain.

   Target
       -c CHANNEL, --channel=CHANNEL
	   Add context fields to a channel named CHANNEL instead of adding
	   them	to all the channels.

       -s SESSION, --session=SESSION
	   Add context fields to a channel in the tracing session named
	   SESSION instead of the current tracing session.

   Context
       --list
	   List	the available context fields. Use this option alone.

       -t TYPE,	--type=TYPE
	   Add context field named TYPE. This option can be repeated as	many
	   times as needed on the command-line.

   Program information
       -h, --help
	   Show	command	help.

	   This	option,	like lttng-help(1), attempts to	launch /usr/bin/man to
	   view	the command's man page.	The path to the	man pager can be
	   overridden by the LTTNG_MAN_BIN_PATH	environment variable.

       --list-options
	   List	available command options.

ENVIRONMENT VARIABLES
       LTTNG_ABORT_ON_ERROR
	   Set to 1 to abort the process after the first error is encountered.

       LTTNG_HOME
	   Overrides the $HOME environment variable. Useful when the user
	   running the commands	has a non-writable home	directory.

       LTTNG_MAN_BIN_PATH
	   Absolute path to the	man pager to use for viewing help information
	   about LTTng commands	(using lttng-help(1) or	lttng COMMAND --help).

       LTTNG_SESSION_CONFIG_XSD_PATH
	   Path	in which the session.xsd session configuration XML schema may
	   be found.

       LTTNG_SESSIOND_PATH
	   Full	session	daemon binary path.

	   The --sessiond-path option has precedence over this environment
	   variable.

       Note that the lttng-create(1) command can spawn an LTTng	session	daemon
       automatically if	none is	running. See lttng-sessiond(8) for the
       environment variables influencing the execution of the session daemon.

FILES
       $LTTNG_HOME/.lttngrc
	   User	LTTng runtime configuration.

	   This	is where the per-user current tracing session is stored
	   between executions of lttng(1). The current tracing session can be
	   set with lttng-set-session(1). See lttng-create(1) for more
	   information about tracing sessions.

       $LTTNG_HOME/lttng-traces
	   Default output directory of LTTng traces. This can be overridden
	   with	the --output option of the lttng-create(1) command.

       $LTTNG_HOME/.lttng
	   User	LTTng runtime and configuration	directory.

       $LTTNG_HOME/.lttng/sessions
	   Default location of saved user tracing sessions (see	lttng-save(1)
	   and lttng-load(1)).

       /usr/local/etc/lttng/sessions
	   System-wide location	of saved tracing sessions (see lttng-save(1)
	   and lttng-load(1)).

	   Note
	   $LTTNG_HOME defaults	to $HOME when not explicitly set.

EXIT STATUS
       0
	   Success

       1
	   Command error

       2
	   Undefined command

       3
	   Fatal error

       4
	   Command warning (something went wrong during	the command)

BUGS
       If you encounter	any issue or usability problem,	please report it on
       the LTTng bug tracker <https://bugs.lttng.org/projects/lttng-tools>.

RESOURCES
       o   LTTng project website <http://lttng.org>

       o   LTTng documentation <http://lttng.org/docs>

       o   Git repositories <http://git.lttng.org>

       o   GitHub organization <http://github.com/lttng>

       o   Continuous integration <http://ci.lttng.org/>

       o   Mailing list	<http://lists.lttng.org> for support and development:
	   lttng-dev@lists.lttng.org

       o   IRC channel <irc://irc.oftc.net/lttng>: #lttng on irc.oftc.net

COPYRIGHTS
       This program is part of the LTTng-tools project.

       LTTng-tools is distributed under	the GNU	General	Public License version
       2 <http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html>. See the
       LICENSE <https://github.com/lttng/lttng-tools/blob/master/LICENSE> file
       for details.

THANKS
       Special thanks to Michel	Dagenais and the DORSAL	laboratory
       <http://www.dorsal.polymtl.ca/> at Ecole	Polytechnique de Montreal for
       the LTTng journey.

       Also thanks to the Ericsson teams working on tracing which helped us
       greatly with detailed bug reports and unusual test cases.

AUTHORS
       LTTng-tools was originally written by Mathieu Desnoyers,	Julien
       Desfossez, and David Goulet. More people	have since contributed to it.

       LTTng-tools is currently	maintained by Jeremie Galarneau
       <mailto:jeremie.galarneau@efficios.com>.

SEE ALSO
       lttng(1)

LTTng 2.9.3			  01/09/2017		  LTTNG-ADD-CONTEXT(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | ENVIRONMENT VARIABLES | FILES | EXIT STATUS | BUGS | RESOURCES | COPYRIGHTS | THANKS | AUTHORS | SEE ALSO

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=lttng-add-context&sektion=1&manpath=FreeBSD+12.2-RELEASE+and+Ports>

home | help