involving multiple concurrent processes and threads. Tracing across multiple
systems is also possible.
-The \fBlttng\fP command line tool from lttng-tools package is used to control
+The \fBlttng\fP command line tool from the lttng-tools package is used to control
both kernel and user-space tracing. Every interactions with the tracer should
be done by this tool or by the liblttng-ctl provided with the lttng-tools
package.
LTTng provides the use of a \fBtracing group\fP (default: tracing). Whomever is
in that group can interact with the root session daemon and thus trace the
kernel. Session daemons can co-exist meaning that you can have a session daemon
-running as Alice that can be use to trace her applications along side with a
-root daemon or even a Bob daemon. We highly recommand to start the session
+running as Alice that can be used to trace her applications along side with a
+root daemon or even a Bob daemon. We highly recommend to start the session
daemon at boot time for stable and long term tracing.
Every user-space applications instrumented with lttng-ust(3), will
.PP
.TP
-.BR "-h, --help"
+.BR "\-h, \-\-help"
Show summary of possible options and commands.
.TP
-.BR "-v, --verbose"
+.BR "\-v, \-\-verbose"
Increase verbosity.
-FIXME : details (-v : sessiond verbose, -vv : consumerd verbose, etc) ?
+Three levels of verbosity are available which are triggered by putting additional v to
+the option (\-vv or \-vvv)
.TP
-.BR "-q, --quiet"
+.BR "\-q, \-\-quiet"
Suppress all messages (even errors).
.TP
-.BR "-g, --group NAME"
+.BR "\-g, \-\-group NAME"
Set unix tracing group name. (default: tracing)
.TP
-.BR "-n, --no-sessiond"
+.BR "\-n, \-\-no-sessiond"
Don't automatically spawn a session daemon.
.TP
-.BR "--sessiond-path"
+.BR "\-\-sessiond\-path"
Set session daemon full binary path.
.TP
-.BR "--list-options"
+.BR "\-\-list\-options"
Simple listing of lttng options.
.TP
-.BR "--list-commands"
+.BR "\-\-list\-commands"
Simple listing of lttng commands.
.SH "COMMANDS"
counters (hardware branch misses and cache misses), to all events in the trace
data output:
-# lttng add-context -k -t prio -t perf:branch-misses -t perf:cache-misses
+# lttng add-context \-k \-t prio \-t perf:branch-misses \-t perf:cache-misses
-Please take a look at the help (-h/--help) for a detailed list of available
+Please take a look at the help (\-h/\-\-help) for a detailed list of available
contexts.
-If no channel and no event is given (-c/-e), the context is added to all
+If no channel and no event is given (\-c/\-e), the context is added to all
channels (which applies automatically to all events in that channel). Otherwise
-the context will be added only to the channel (-c) and/or event (-e) indicated.
+the context will be added only to the channel (\-c) and/or event (\-e) indicated.
-If \fB-s, --session\fP is omitted, the session name is taken from the .lttngrc
+If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc
file.
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
--s, --session NAME
+\-s, \-\-session NAME
Apply on session name.
--c, --channel NAME
+\-c, \-\-channel NAME
Apply on channel name.
--e, --event NAME
+\-e, \-\-event NAME
Apply on event name.
--k, --kernel
+\-k, \-\-kernel
Apply for the kernel tracer
--u, --userspace
+\-u, \-\-userspace
Apply for the user-space tracer
--t, --type TYPE
+\-t, \-\-type TYPE
Context type. You can repeat this option on the command line. Please
- use "lttng add-context -h" to list all available types.
+ use "lttng add-context \-h" to list all available types.
.fi
.IP
This sequence of commands will gather a trace executing a kretprobe hooked on
an empty function, gathering PMU counters LLC (Last Level Cache) misses
-information (see lttng add-context --help to see the list of available PMU
+information (see lttng add-context \-\-help to see the list of available PMU
counters).
# lttng create calibrate-function
-# lttng enable-event calibrate --kernel --function lttng_calibrate_kretprobe
-# lttng add-context --kernel -t perf:LLC-load-misses -t perf:LLC-store-misses \\
- -t perf:LLC-prefetch-misses
+# lttng enable-event calibrate \-\-kernel \-\-function lttng_calibrate_kretprobe
+# lttng add-context \-\-kernel \-t perf:LLC-load-misses \-t perf:LLC-store-misses \\
+ \-t perf:LLC-prefetch-misses
# lttng start
# for a in $(seq 1 10); do \\
- lttng calibrate --kernel --function;
+ lttng calibrate \-\-kernel \-\-function;
done
# lttng destroy
-# babeltrace $(ls -1drt ~/lttng-traces/calibrate-function-* | tail -n 1)
+# babeltrace $(ls \-1drt ~/lttng-traces/calibrate-function-* | tail \-n 1)
The output from babeltrace can be saved to a text file and opened in a
spreadsheet (e.g. oocalc) to focus on the per-PMU counter delta between
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
--k, --kernel
+\-k, \-\-kernel
Apply for the kernel tracer
--u, --userspace
+\-u, \-\-userspace
Apply for the user-space tracer
---function
+\-\-function
Dynamic function entry/return probe (default)
.fi
On creation, a \fB.lttngrc\fP file is created in your $HOME directory
containing the current session name. If NAME is omitted, a session name is
-automatically created having this form: 'auto-yyyymmdd-hhmms'.
+automatically created having this form: 'auto-yyyymmdd-hhmmss'.
-If no \fB-o, --output\fP is specified, the traces will be written in
+If no \fB\-o, \-\-output\fP is specified, the traces will be written in
$HOME/lttng-traces.
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
--o, --output PATH
+\-o, \-\-output PATH
Specify output path for traces
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-a, \-\-all
+ Destroy all sessions
+\-\-list-options
Simple listing of options
.fi
.nf
Enable tracing channel
-If \fB-s, --session\fP is omitted, the session name is taken from the .lttngrc
+To enable event, you must first enable a channel which contains event(s).
+
+If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc
file.
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show this help
---list-options
+\-\-list-options
Simple listing of options
--s, --session
+\-s, \-\-session
Apply on session name
--k, --kernel
+\-k, \-\-kernel
Apply to the kernel tracer
--u, --userspace
+\-u, \-\-userspace
Apply to the user-space tracer
---discard
+\-\-discard
Discard event when subbuffers are full (default)
---overwrite
+\-\-overwrite
Flight recorder mode : overwrites events when subbuffers are full
---subbuf-size
+\-\-subbuf-size
Subbuffer size in bytes (default: 4096, kernel default: 262144)
---num-subbuf
- Number of subbufers (default: 8, kernel default: 4)
---switch-timer
+\-\-num-subbuf
+ Number of subbuffers (default: 4)
+ Needs to be a power of 2 for kernel and ust tracers
+\-\-switch-timer
Switch subbuffer timer interval in usec (default: 0)
---read-timer
+ Needs to be a power of 2 for kernel and ust tracers
+\-\-read-timer
Read timer interval in usec (default: 200)
.fi
.nf
Enable tracing event
-A tracing event is always assigned to a channel. If \fB-c, --channel\fP is
+A tracing event is always assigned to a channel. If \fB\-c, \-\-channel\fP is
omitted, a default channel named '\fBchannel0\fP' is created and the event is
-added to it. For the user-space tracer, using \fB-a, --all\fP is the same as
+added to it. For the user-space tracer, using \fB\-a, \-\-all\fP is the same as
using the wildcard "*".
-If \fB-s, --session\fP is omitted, the session name is taken from the .lttngrc
+If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc
file.
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
--s, --session
+\-s, \-\-session
Apply on session name
--c, --channel
+\-c, \-\-channel
Apply on channel name
--a, --all
- Enable all tracepoints
--k, --kernel
+\-a, \-\-all
+ Enable all tracepoints and syscalls
+\-k, \-\-kernel
Apply for the kernel tracer
--u, --userspace
+\-u, \-\-userspace
Apply for the user-space tracer
---tracepoint
+\-\-tracepoint
Tracepoint event (default)
- userspace tracer supports wildcards at end of string. Don't forget to
quote to deal with bash expansion.
e.g.:
"*"
"app_component:na*"
---loglevel
+\-\-loglevel
Tracepoint loglevel
---probe [addr | symbol | symbol+offset]
+\-\-probe [addr | symbol | symbol+offset]
Dynamic probe. Addr and offset can be octal (0NNN...), decimal (NNN...)
or hexadecimal (0xNNN...)
---function [addr | symbol | symbol+offset]
+\-\-function [addr | symbol | symbol+offset]
Dynamic function entry/return probe. Addr and offset can be octal
(0NNN...), decimal (NNN...) or hexadecimal (0xNNN...)
---syscall
+\-\-syscall
System call event
Enabling syscalls tracing (kernel tracer), you will not be able to disable them
with disable-event. This is a known limitation. You can disable the entire
channel to do the trick.
+\-\-filter 'expression'
+ Set a filter on a newly enabled event.
+ Filter expression on event fields event recording
+ depends on evaluation. Only specify on first activation
+ of a given event within a session. Filter only allowed
+ when enabling events within a session before tracing is
+ started.
.fi
-.IP "\fBdisable-channel\fP NAME[,NAME2,...] [-k|-u] [OPTIONS]"
+.IP "\fBdisable-channel\fP NAME[,NAME2,...] [\-k|\-u] [OPTIONS]"
.nf
Disable tracing channel
Disabling a channel makes all event(s) in that channel to stop tracing. You can
enable it back by calling \fBlttng enable-channel NAME\fP again.
-If \fB-s, --session\fP is omitted, the session name is taken from the .lttngrc
+If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc
file.
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
--s, --session
+\-s, \-\-session
Apply on session name
--k, --kernel
+\-k, \-\-kernel
Apply for the kernel tracer
--u, --userspace
+\-u, \-\-userspace
Apply for the user-space tracer
.fi
-.IP "\fBdisable-event\fP NAME[,NAME2,...] [-k|-u] [OPTIONS]"
+.IP "\fBdisable-event\fP NAME[,NAME2,...] [\-k|\-u] [OPTIONS]"
.nf
Disable tracing event
The event, once disabled, can be re-enabled by calling \fBlttng enable-event
NAME\fP again.
-If \fB-s, --session\fP is omitted, the session name is taken from the .lttngrc
+If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc
file.
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
--s, --session
+\-s, \-\-session
Apply on session name
--k, --kernel
+\-k, \-\-kernel
Apply for the kernel tracer
--u, --userspace
+\-u, \-\-userspace
Apply for the user-space tracer
.fi
-.IP "\fBlist\fP [-k|-u] [SESSION [SESSION_OPTIONS]]"
+.IP "\fBlist\fP [\-k|\-u] [SESSION [SESSION_OPTIONS]]"
.nf
-List tracing session informations.
+List tracing session information.
With no arguments, it will list available tracing session(s).
-With -k alone, it will list all available kernel events (except the system
+With the session name, it will display the details of the session including
+the trace file path, the associated channels and their state (activated
+and deactivated), the activated events and more.
+
+With \-k alone, it will list all available kernel events (except the system
calls events).
-With -u alone, it will list all available user-space events from registered
-applications. Here is an example of 'lttng list -u':
+With \-u alone, it will list all available user-space events from registered
+applications. Here is an example of 'lttng list \-u':
PID: 7448 - Name: /tmp/lttng-ust/tests/hello/.libs/lt-hello
ust_tests_hello:tptest_sighandler (type: tracepoint)
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
--k, --kernel
- Select kernel domain (FIXME : apparition de la notion de "domain" ici)
--u, --userspace
+\-k, \-\-kernel
+ Select kernel domain
+\-u, \-\-userspace
Select user-space domain.
Session options:
--c, --channel NAME
+\-c, \-\-channel NAME
List details of a channel
--d, --domain
+\-d, \-\-domain
List available domain(s)
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show summary of possible options and commands.
---list-options
+\-\-list-options
Simple listing of options
.fi
By default, the babeltrace viewer will be used for text viewing.
-The SESSION_NAME is an optional session name. If not specified, lttng will get
-it from the configuration file (.lttngrc).
+If SESSION_NAME is omitted, the session name is taken from the .lttngrc file.
+
.fi
.B OPTIONS:
.nf
--h, --help
+\-h, \-\-help
Show this help
---list-options
+\-\-list-options
Simple listing of options
--t, --trace-path PATH
+\-t, \-\-trace-path PATH
Trace directory path for the viewer
--e, --viewer CMD
+\-e, \-\-viewer CMD
Specify viewer and/or options to use
This will completely override the default viewers so
please make sure to specify the full command. The trace
to the arguments
.fi
+.SH "EXIT VALUES"
+
+.IP "0"
+Success
+
+.IP "1"
+Command error
+
+.IP "2"
+Undefined command
+
+.IP "3"
+Fatal error
+
+.IP "4"
+Command warning
+
+.IP "16"
+No session found by the name given
+
+.IP "18"
+Error in session creation
+
+.IP "21"
+Error in application(s) listing
+
+.IP "28"
+Session name already exists
+
+.IP "33"
+Kernel tracer unavailable
+
+.IP "35"
+Kernel event exists
+
+.IP "37"
+Kernel channel exists
+
+.IP "38"
+Kernel channel creation failed
+
+.IP "39"
+Kernel channel not found
+
+.IP "40"
+Kernel channel disable failed
+
+.IP "41"
+Kernel channel enable failed
+
+.IP "42"
+Kernel context failed
+
+.IP "43"
+Kernel enable event failed
+
+.IP "44"
+Kernel disable event failed
+
+.IP "53"
+Kernel listing events failed
+
+.IP "60"
+UST channel disable failed
+
+.IP "61"
+UST channel enable failed
+
+.IP "62"
+UST adding context failed
+
+.IP "63"
+UST event enable failed
+
+.IP "64"
+UST event disable failed
+
+.IP "66"
+UST start failed
+
+.IP "67"
+UST stop failed
+
+.IP "75"
+UST event exists
+
+.IP "76"
+UST event not found
+
+.IP "77"
+UST context exists
+
+.IP "78"
+UST invalid context
+
+.IP "79"
+Tracing the kernel requires a root lttng-sessiond daemon and "tracing" group
+user membership.
+
+.IP "80"
+Tracing already started
+
+.IP "81"
+Tracing already stopped
+
+.IP "98"
+No UST consumer detected
+
+.IP "99"
+No Kernel consumer detected
+
+.IP "100"
+Event already enabled with different loglevel
+.PP
.SH "ENVIRONMENT VARIABLES"
.PP
.PP
.PP
-.IP "LTTNG_SESSIOND_PATH_ENV"
-Allows to specify the full session daemon binary path to lttng command line
-tool. You can also use --sessiond-path option having the same effect.
+.IP "LTTNG_SESSIOND_PATH"
+Allows one to specify the full session daemon binary path to lttng command line
+tool. You can also use \-\-sessiond-path option having the same effect.
.SH "SEE ALSO"
.PP
.SH "BUGS"
.PP
-No show stopper bugs known yet at this stable version.
+No show stopper bugs are known yet in this version.
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.
.SH "CREDITS"
.PP
-lttng is distributed under the GNU public license version 2. See the file
+lttng is distributed under the GNU General Public License version 2. See the file
COPYING for details.
.PP
A Web site is available at http://lttng.org for more information on the LTTng
.PP
Thanks to Yannick Brosseau without whom this project would never have been so
lean and mean! Also thanks to the Ericsson teams working on tracing which
-helped us greatly with detailled bug reports and unusual test cases.
+helped us greatly with detailed bug reports and unusual test cases.
Thanks to our beloved packager Alexandre Montplaisir-Goncalves (Ubuntu and PPA
maintainer) and Jon Bernard for our Debian packages.
Special thanks to Michel Dagenais and the DORSAL laboratory at Polytechnique de
Montreal for the LTTng journey.
-.pp
+.PP
.SH "AUTHORS"
.PP