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516f6cbe | 1 | .TH "LTTNG" "1" "May 13th, 2014" "" "" |
6991b181 DG |
2 | |
3 | .SH "NAME" | |
94ffb05d | 4 | lttng \- LTTng 2.x tracer control command line tool |
6991b181 DG |
5 | |
6 | .SH "SYNOPSIS" | |
7 | ||
8 | .PP | |
6991b181 | 9 | lttng [OPTIONS] <COMMAND> |
6991b181 DG |
10 | .SH "DESCRIPTION" |
11 | ||
12 | .PP | |
13 | The LTTng project aims at providing highly efficient tracing tools for Linux. | |
e256d661 | 14 | Its tracers help track down performance issues and debug problems |
6991b181 DG |
15 | involving multiple concurrent processes and threads. Tracing across multiple |
16 | systems is also possible. | |
17 | ||
fa072eae | 18 | The \fBlttng\fP command line tool from the lttng-tools package is used to control |
e256d661 JG |
19 | both kernel and user-space tracing. Every interaction with the tracer should |
20 | be done by this tool or by the liblttng-ctl library provided by the lttng-tools | |
6991b181 DG |
21 | package. |
22 | ||
23 | LTTng uses a session daemon (lttng-sessiond(8)), acting as a tracing registry, | |
50a3b92a | 24 | which allows you to interact with multiple tracers (kernel and user-space) |
6991b181 DG |
25 | inside the same container, a tracing session. Traces can be gathered from the |
26 | kernel and/or instrumented applications (lttng-ust(3)). Aggregating and reading | |
27 | those traces is done using the babeltrace(1) text viewer. | |
28 | ||
50a3b92a | 29 | We introduce the notion of \fBtracing domains\fP which is essentially a type of |
0e115563 DG |
30 | tracer (kernel, user space, JUL, LOG4J or Python for now). In the future, we |
31 | could see more tracer like for instance an hypervisor. For some commands, | |
32 | you'll need to specify on which domain the command operates (\-u, \-k, \-l, \-j | |
33 | or \-p). For instance, the kernel domain must be specified when enabling a | |
34 | kernel event. | |
50a3b92a | 35 | |
6991b181 DG |
36 | In order to trace the kernel, the session daemon needs to be running as root. |
37 | LTTng provides the use of a \fBtracing group\fP (default: tracing). Whomever is | |
38 | in that group can interact with the root session daemon and thus trace the | |
e256d661 | 39 | kernel. Session daemons can co-exist, meaning that you can have a session daemon |
fa072eae | 40 | running as Alice that can be used to trace her applications along side with a |
e256d661 | 41 | root daemon or even a Bob daemon. We highly recommend starting the session |
6991b181 DG |
42 | daemon at boot time for stable and long term tracing. |
43 | ||
274d6c5d DG |
44 | Each user-space application instrumented with lttng-ust(3) will automatically |
45 | register with the root session daemon and its user session daemon. This allows | |
46 | each daemon to list the available traceable applications and tracepoints at any | |
47 | given moment (See the \fBlist\fP command). | |
6991b181 DG |
48 | .SH "OPTIONS" |
49 | ||
50 | .PP | |
c0fdca17 | 51 | This program follows the usual GNU command line syntax with long options starting with |
6991b181 DG |
52 | two dashes. Below is a summary of the available options. |
53 | .PP | |
54 | ||
55 | .TP | |
c9e32613 | 56 | .BR "\-h, \-\-help" |
6991b181 DG |
57 | Show summary of possible options and commands. |
58 | .TP | |
c0fdca17 JG |
59 | .BR "\-V, \-\-version" |
60 | Show version. | |
61 | .TP | |
c9e32613 | 62 | .BR "\-v, \-\-verbose" |
6991b181 | 63 | Increase verbosity. |
d829b38c | 64 | Three levels of verbosity are available which are triggered by putting additional v to |
fa072eae | 65 | the option (\-vv or \-vvv) |
6991b181 | 66 | .TP |
c9e32613 | 67 | .BR "\-q, \-\-quiet" |
6991b181 DG |
68 | Suppress all messages (even errors). |
69 | .TP | |
c9e32613 | 70 | .BR "\-g, \-\-group NAME" |
6991b181 DG |
71 | Set unix tracing group name. (default: tracing) |
72 | .TP | |
c9e32613 | 73 | .BR "\-n, \-\-no-sessiond" |
6991b181 DG |
74 | Don't automatically spawn a session daemon. |
75 | .TP | |
391b9c72 | 76 | .BR "\-\-sessiond\-path PATH" |
6991b181 DG |
77 | Set session daemon full binary path. |
78 | .TP | |
c9e32613 | 79 | .BR "\-\-list\-options" |
6991b181 DG |
80 | Simple listing of lttng options. |
81 | .TP | |
c9e32613 | 82 | .BR "\-\-list\-commands" |
6991b181 | 83 | Simple listing of lttng commands. |
ed43168a JRJ |
84 | .TP |
85 | .BR "\-m, \-\-mi TYPE | |
86 | Machine interface | |
87 | ||
88 | TYPE supported: XML | |
89 | ||
90 | Machine interface (MI) mode converts the traditional pretty printing to a | |
91 | machine output syntax. MI mode provides a format change-resistant way to access | |
92 | information generated via the lttng command line. | |
93 | ||
94 | When using MI mode, the data is printed on \fBstdout\fP. Error and warning are | |
95 | printed on \fBstderr\fP with the pretty print default format. | |
96 | ||
97 | If any errors occur during the execution of a command, the return value of the | |
98 | command will be different than zero. In this case, lttng does NOT guarantee the | |
99 | syntax and data validity of the generated MI output. | |
100 | ||
101 | For XML output type, a schema definition (XSD) file used for validation can be | |
102 | found under src/common/mi_lttng.xsd | |
103 | ||
6991b181 DG |
104 | .SH "COMMANDS" |
105 | ||
812a5eb7 | 106 | .PP |
ee2758e5 | 107 | \fBadd-context\fP [OPTIONS] |
812a5eb7 | 108 | .RS |
6991b181 DG |
109 | Add context to event(s) and/or channel(s). |
110 | ||
391b9c72 DG |
111 | A context is basically extra information appended to a channel. For instance, |
112 | you could ask the tracer to add the PID information for all events in a | |
113 | channel. You can also add performance monitoring unit counters (perf PMU) using | |
aa3514e9 | 114 | the perf kernel API. |
6991b181 | 115 | |
aa3514e9 MD |
116 | For example, this command will add the context information 'prio' and two per-CPU |
117 | perf counters (hardware branch misses and cache misses), to all events in the trace | |
6991b181 DG |
118 | data output: |
119 | ||
812a5eb7 | 120 | .nf |
aa3514e9 MD |
121 | # lttng add-context \-k \-t prio \-t perf:cpu:branch-misses \\ |
122 | \-t perf:cpu:cache-misses | |
812a5eb7 | 123 | .fi |
6991b181 | 124 | |
c9e32613 | 125 | Please take a look at the help (\-h/\-\-help) for a detailed list of available |
6991b181 DG |
126 | contexts. |
127 | ||
aa3514e9 MD |
128 | Perf counters are available as per-CPU ("perf:cpu:...") and per-thread |
129 | ("perf:thread:...") counters. Currently, per-CPU counters can only be | |
130 | used with the kernel tracing domain, and per-thread counters can only be | |
131 | used with the UST tracing domain. | |
132 | ||
bd337b98 DG |
133 | If no channel is given (\-c), the context is added to all channels that were |
134 | already enabled. If the session has no channel, a default channel is created. | |
31ea4846 | 135 | Otherwise the context will be added only to the given channel (\-c). |
6991b181 | 136 | |
c9e32613 | 137 | If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc |
6991b181 | 138 | file. |
6991b181 DG |
139 | |
140 | .B OPTIONS: | |
141 | ||
812a5eb7 MD |
142 | .TP |
143 | .BR "\-h, \-\-help" | |
144 | Show summary of possible options and commands. | |
145 | .TP | |
146 | .BR "\-s, \-\-session NAME" | |
147 | Apply on session name. | |
148 | .TP | |
149 | .BR "\-c, \-\-channel NAME" | |
150 | Apply on channel name. | |
151 | .TP | |
152 | .BR "\-k, \-\-kernel" | |
153 | Apply for the kernel tracer | |
154 | .TP | |
155 | .BR "\-u, \-\-userspace" | |
156 | Apply for the user-space tracer | |
157 | .TP | |
158 | .BR "\-t, \-\-type TYPE" | |
159 | Context type. You can repeat this option on the command line. Please | |
160 | use "lttng add-context \-h" to list all available types. | |
161 | .RE | |
162 | .PP | |
6991b181 | 163 | |
22019883 MD |
164 | .PP |
165 | \fBcalibrate\fP [OPTIONS] | |
166 | .RS | |
6991b181 DG |
167 | Quantify LTTng overhead |
168 | ||
169 | The LTTng calibrate command can be used to find out the combined average | |
170 | overhead of the LTTng tracer and the instrumentation mechanisms used. This | |
171 | overhead can be calibrated in terms of time or using any of the PMU performance | |
172 | counter available on the system. | |
173 | ||
174 | For now, the only calibration implemented is that of the kernel function | |
175 | instrumentation (kretprobes). | |
176 | ||
177 | * Calibrate kernel function instrumentation | |
178 | ||
179 | Let's use an example to show this calibration. We use an i7 processor with 4 | |
180 | general-purpose PMU registers. This information is available by issuing dmesg, | |
181 | looking for "generic registers". | |
182 | ||
183 | This sequence of commands will gather a trace executing a kretprobe hooked on | |
184 | an empty function, gathering PMU counters LLC (Last Level Cache) misses | |
c9e32613 | 185 | information (see lttng add-context \-\-help to see the list of available PMU |
6991b181 DG |
186 | counters). |
187 | ||
22019883 | 188 | .nf |
6991b181 | 189 | # lttng create calibrate-function |
22019883 MD |
190 | # lttng enable-event calibrate \-\-kernel \\ |
191 | \-\-function lttng_calibrate_kretprobe | |
aa3514e9 MD |
192 | # lttng add-context \-\-kernel \-t perf:cpu:LLC-load-misses \\ |
193 | \-t perf:cpu:LLC-store-misses \\ | |
194 | \-t perf:cpu:LLC-prefetch-misses | |
6991b181 DG |
195 | # lttng start |
196 | # for a in $(seq 1 10); do \\ | |
c9e32613 | 197 | lttng calibrate \-\-kernel \-\-function; |
6991b181 DG |
198 | done |
199 | # lttng destroy | |
22019883 MD |
200 | # babeltrace $(ls \-1drt ~/lttng-traces/calibrate-function-* \\ |
201 | | tail \-n 1) | |
202 | .fi | |
6991b181 DG |
203 | |
204 | The output from babeltrace can be saved to a text file and opened in a | |
205 | spreadsheet (e.g. oocalc) to focus on the per-PMU counter delta between | |
206 | consecutive "calibrate_entry" and "calibrate_return" events. Note that these | |
207 | counters are per-CPU, so scheduling events would need to be present to account | |
208 | for migration between CPU. Therefore, for calibration purposes, only events | |
209 | staying on the same CPU must be considered. | |
210 | ||
211 | The average result, for the i7, on 10 samples: | |
212 | ||
22019883 | 213 | .nf |
6991b181 DG |
214 | Average Std.Dev. |
215 | perf_LLC_load_misses: 5.0 0.577 | |
216 | perf_LLC_store_misses: 1.6 0.516 | |
217 | perf_LLC_prefetch_misses: 9.0 14.742 | |
22019883 | 218 | .fi |
6991b181 DG |
219 | |
220 | As we can notice, the load and store misses are relatively stable across runs | |
221 | (their standard deviation is relatively low) compared to the prefetch misses. | |
222 | We can conclude from this information that LLC load and store misses can be | |
223 | accounted for quite precisely, but prefetches within a function seems to behave | |
224 | too erratically (not much causality link between the code executed and the CPU | |
225 | prefetch activity) to be accounted for. | |
6991b181 DG |
226 | |
227 | .B OPTIONS: | |
228 | ||
22019883 MD |
229 | .TP |
230 | .BR "\-h, \-\-help" | |
231 | Show summary of possible options and commands. | |
232 | .TP | |
233 | .BR "\-k, \-\-kernel" | |
234 | Apply for the kernel tracer | |
235 | .TP | |
236 | .BR "\-u, \-\-userspace" | |
237 | Apply for the user-space tracer | |
238 | .TP | |
239 | .BR "\-\-function" | |
240 | Dynamic function entry/return probe (default) | |
241 | .RE | |
242 | .PP | |
6991b181 | 243 | |
ee2758e5 | 244 | .PP |
feb3ca56 | 245 | \fBcreate\fP [NAME] [OPTIONS] |
ee2758e5 | 246 | .RS |
6991b181 DG |
247 | Create tracing session. |
248 | ||
249 | A tracing session contains channel(s) which contains event(s). It is domain | |
e256d661 | 250 | agnostic, meaning that channels and events can be enabled for the |
6991b181 DG |
251 | user-space tracer and/or the kernel tracer. It acts like a container |
252 | aggregating multiple tracing sources. | |
253 | ||
254 | On creation, a \fB.lttngrc\fP file is created in your $HOME directory | |
255 | containing the current session name. If NAME is omitted, a session name is | |
fa072eae | 256 | automatically created having this form: 'auto-yyyymmdd-hhmmss'. |
6991b181 | 257 | |
c9e32613 | 258 | If no \fB\-o, \-\-output\fP is specified, the traces will be written in |
6991b181 | 259 | $HOME/lttng-traces. |
feb0f3e5 AM |
260 | |
261 | The $HOME environment variable can be overridden by defining the environment | |
262 | variable LTTNG_HOME. This is useful when the user running the commands has | |
263 | a non-writeable home directory. | |
6991b181 | 264 | |
1c1c3634 DG |
265 | The session name MUST NOT contain the character '/'. |
266 | ||
6991b181 DG |
267 | .B OPTIONS: |
268 | ||
ee2758e5 MD |
269 | .TP |
270 | .BR "\-h, \-\-help" | |
271 | Show summary of possible options and commands. | |
272 | .TP | |
273 | .BR "\-\-list-options" | |
274 | Simple listing of options | |
275 | .TP | |
276 | .BR "\-o, \-\-output PATH" | |
277 | Specify output path for traces | |
278 | .TP | |
96fe6b8d DG |
279 | .BR "\-\-no-output" |
280 | Traces will not be output | |
281 | .TP | |
ee2758e5 | 282 | .BR "\-\-snapshot" |
96fe6b8d DG |
283 | Set the session in snapshot mode. Created in no-output mode and uses the |
284 | URL, if one is specified, as the default snapshot output. Every channel will be set | |
ee2758e5 | 285 | in overwrite mode and with mmap output (splice not supported). |
0794f51b | 286 | .TP |
d73c5802 | 287 | .BR "\-\-live [USEC]" |
eb82f91d | 288 | Set the session exclusively in live mode. The parameter is the delay in micro |
0794f51b DG |
289 | seconds before the data is flushed and streamed. The live mode allows you to |
290 | stream the trace and view it while it's being recorded by any tracer. For that, | |
291 | you need a lttng-relayd and this session requires a network URL (\-U or | |
d73c5802 DG |
292 | \-C/\-D). If no USEC nor URL is provided, the default is to use a timer value |
293 | set to 1000000 and the network URL set to net://127.0.0.1. | |
0794f51b DG |
294 | |
295 | To read a live session, you can use babeltrace(1) or the live streaming | |
296 | protocol in doc/live-reading-protocol.txt. Here is an example: | |
297 | ||
298 | .nf | |
299 | $ lttng-relayd -o /tmp/lttng | |
300 | $ lttng create --live 200000 -U net://localhost | |
301 | $ lttng enable-event -a --userspace | |
302 | $ lttng start | |
303 | .fi | |
304 | ||
305 | After the start, you'll be able to read the events while they are being | |
306 | recorded in /tmp/lttng. | |
6b8f2e64 | 307 | |
d7ba1388 MD |
308 | .TP |
309 | .BR "\-\-shm-path PATH" | |
310 | ||
311 | Path where shared memory holding buffers should be created. Useful | |
6a9a8e6a JG |
312 | when used with PRAMFS or other persistent memory filesystems to extract |
313 | trace data in the event of a crash requiring a reboot. | |
d7ba1388 | 314 | |
464bd4b0 JR |
315 | See the \fBlttng-crash(1)\fP utility for more information on crash recovery. |
316 | ||
ee2758e5 MD |
317 | .TP |
318 | .BR "\-U, \-\-set-url=URL" | |
319 | Set URL for the consumer output destination. It is persistent for the | |
320 | session lifetime. Redo the command to change it. This will set both data | |
321 | and control URL for network. | |
322 | .TP | |
323 | .BR "\-C, \-\-ctrl-url=URL" | |
324 | Set control path URL. (Must use -D also) | |
325 | .TP | |
326 | .BR "\-D, \-\-data-url=URL" | |
327 | Set data path URL. (Must use -C also) | |
328 | .PP | |
6b8f2e64 DG |
329 | Using these options, each API call can be controlled individually. For |
330 | instance, \-C does not enable the consumer automatically. You'll need the \-e | |
331 | option for that. | |
332 | ||
785d2d0d DG |
333 | .B URL FORMAT: |
334 | ||
335 | proto://[HOST|IP][:PORT1[:PORT2]][/TRACE_PATH] | |
336 | ||
337 | Supported protocols are (proto): | |
ee2758e5 MD |
338 | .TP |
339 | .BR "file://..." | |
340 | Local filesystem full path. | |
785d2d0d | 341 | |
ee2758e5 MD |
342 | .TP |
343 | .BR "net://..." | |
344 | This will use the default network transport layer which is TCP for both | |
345 | control (PORT1) and data port (PORT2). The default ports are | |
346 | respectively 5342 and 5343. Note that net[6]:// is not yet supported. | |
785d2d0d | 347 | |
ee2758e5 MD |
348 | .TP |
349 | .BR "tcp[6]://..." | |
350 | Can only be used with -C and -D together | |
785d2d0d DG |
351 | |
352 | NOTE: IPv6 address MUST be enclosed in brackets '[]' (rfc2732) | |
6b8f2e64 DG |
353 | |
354 | .B EXAMPLES: | |
355 | ||
ee2758e5 | 356 | .nf |
6b8f2e64 | 357 | # lttng create -U net://192.168.1.42 |
ee2758e5 | 358 | .fi |
6b8f2e64 DG |
359 | Uses TCP and default ports for the given destination. |
360 | ||
ee2758e5 | 361 | .nf |
6b8f2e64 | 362 | # lttng create -U net6://[fe80::f66d:4ff:fe53:d220] |
ee2758e5 | 363 | .fi |
6b8f2e64 DG |
364 | Uses TCP, default ports and IPv6. |
365 | ||
ee2758e5 | 366 | .nf |
6b8f2e64 | 367 | # lttng create s1 -U net://myhost.com:3229 |
6991b181 | 368 | .fi |
ee2758e5 MD |
369 | Create session s1 and set its consumer to myhost.com on port 3229 for control. |
370 | .RE | |
371 | .PP | |
6991b181 | 372 | |
f2b14ef1 MD |
373 | .PP |
374 | \fBdestroy\fP [NAME] [OPTIONS] | |
375 | .RS | |
6991b181 DG |
376 | Teardown tracing session |
377 | ||
378 | Free memory on the session daemon and tracer side. It's gone! | |
379 | ||
380 | If NAME is omitted, the session name is taken from the .lttngrc file. | |
6991b181 DG |
381 | |
382 | .B OPTIONS: | |
383 | ||
f2b14ef1 MD |
384 | .TP |
385 | .BR "\-h, \-\-help" | |
386 | Show summary of possible options and commands. | |
387 | .TP | |
388 | .BR "\-a, \-\-all" | |
389 | Destroy all sessions | |
390 | .TP | |
391 | .BR "\-\-list-options" | |
392 | Simple listing of options | |
393 | .RE | |
394 | .PP | |
6991b181 | 395 | |
05be3802 MD |
396 | .PP |
397 | \fBenable-channel\fP NAME[,NAME2,...] (\-k | \-u) [OPTIONS] | |
398 | .RS | |
6991b181 DG |
399 | Enable tracing channel |
400 | ||
004f3466 DG |
401 | To enable an event, you must enable both the event and the channel that |
402 | contains it. | |
b883c01b | 403 | |
c9e32613 | 404 | If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc |
6991b181 | 405 | file. |
7972aab2 | 406 | |
05be3802 MD |
407 | Exactly one of \-k or -u must be specified. |
408 | ||
7972aab2 | 409 | It is important to note that if a certain type of buffers is used, the session |
bd337b98 | 410 | will be set with that type and all other subsequent channel needs to have the |
7972aab2 | 411 | same type. |
bd337b98 | 412 | |
d2f11c4a DG |
413 | Note that once the session has been started and enabled on the tracer side, |
414 | it's not possible anymore to enable a new channel for that session. | |
6991b181 DG |
415 | |
416 | .B OPTIONS: | |
417 | ||
05be3802 MD |
418 | .TP |
419 | .BR "\-h, \-\-help" | |
420 | Show this help | |
421 | .TP | |
422 | .BR "\-\-list-options" | |
423 | Simple listing of options | |
424 | .TP | |
425 | .BR "\-s, \-\-session NAME" | |
426 | Apply on session name | |
427 | .TP | |
428 | .BR "\-k, \-\-kernel" | |
429 | Apply to the kernel tracer | |
430 | .TP | |
431 | .BR "\-u, \-\-userspace" | |
432 | Apply to the user-space tracer | |
433 | .TP | |
434 | .BR "\-\-discard" | |
435 | Discard event when subbuffers are full (default) | |
436 | .TP | |
437 | .BR "\-\-overwrite" | |
33fbd469 DG |
438 | Flight recorder mode: overwrites events when subbuffers are full. The |
439 | number of subbuffer must be 2 or more. | |
05be3802 MD |
440 | .TP |
441 | .BR "\-\-subbuf-size SIZE" | |
442 | Subbuffer size in bytes {+k,+M,+G}. | |
443 | (default UST uid: 131072, UST pid: 4096, kernel: 262144, metadata: 4096) | |
444 | Rounded up to the next power of 2. | |
445 | ||
446 | The minimum subbuffer size, for each tracer, is the max value between | |
447 | the default above and the system page size. You can issue this command | |
448 | to get the current page size on your system: \fB$ getconf PAGE_SIZE\fP | |
449 | .TP | |
450 | .BR "\-\-num-subbuf NUM" | |
451 | Number of subbuffers. (default UST uid: 4, UST pid: 4, kernel: 4, | |
452 | metadata: 2) Rounded up to the next power of 2. | |
453 | .TP | |
454 | .BR "\-\-switch-timer USEC" | |
455 | Switch subbuffer timer interval in µsec. | |
456 | (default UST uid: 0, UST pid: 0, kernel: 0, metadata: 0) | |
457 | .TP | |
458 | .BR "\-\-read-timer USEC" | |
459 | Read timer interval in µsec. | |
460 | (default UST uid: 0, UST pid: 0, kernel: 200000, metadata: 0) | |
461 | .TP | |
462 | .BR "\-\-output TYPE" | |
463 | Channel output type. Possible values: mmap, splice | |
464 | (default UST uid: mmap, UST pid: mmap, kernel: splice, metadata: mmap) | |
465 | .TP | |
466 | .BR "\-\-buffers-uid" | |
467 | Use per UID buffer (\-u only). Buffers are shared between applications | |
468 | that have the same UID. | |
469 | .TP | |
470 | .BR "\-\-buffers-pid" | |
471 | Use per PID buffer (\-u only). Each application has its own buffers. | |
472 | .TP | |
473 | .BR "\-\-buffers-global" | |
474 | Use shared buffer for the whole system (\-k only) | |
475 | .TP | |
476 | .BR "\-C, \-\-tracefile-size SIZE" | |
477 | Maximum size of each tracefile within a stream (in bytes). | |
478 | 0 means unlimited. (default: 0) | |
c0684a0d | 479 | Note: traces generated with this option may inaccurately report |
a10f04ad | 480 | discarded events as of CTF 1.8. |
05be3802 MD |
481 | .TP |
482 | .BR "\-W, \-\-tracefile-count COUNT" | |
483 | Used in conjunction with \-C option, this will limit the number of files | |
484 | created to the specified count. 0 means unlimited. (default: 0) | |
1624d5b7 JD |
485 | |
486 | .B EXAMPLES: | |
487 | ||
05be3802 MD |
488 | .nf |
489 | $ lttng enable-channel -k -C 4096 -W 32 chan1 | |
490 | .fi | |
e256d661 | 491 | For each stream, the maximum size of each trace file will be 4096 bytes and |
cea28771 | 492 | there will be a maximum of 32 different files. The file count is appended after |
1624d5b7 JD |
493 | the stream number as seen in the following example. The last trace file is |
494 | smaller than 4096 since it was not completely filled. | |
495 | ||
05be3802 | 496 | .nf |
1624d5b7 JD |
497 | ~/lttng-traces/[...]/chan1_0_0 (4096) |
498 | ~/lttng-traces/[...]/chan1_0_1 (4096) | |
499 | ~/lttng-traces/[...]/chan1_0_2 (3245) | |
500 | ~/lttng-traces/[...]/chan1_1_0 (4096) | |
501 | ... | |
05be3802 | 502 | .fi |
1624d5b7 | 503 | |
05be3802 MD |
504 | .nf |
505 | $ lttng enable-channel -k -C 4096 | |
506 | .fi | |
1624d5b7 JD |
507 | This will create trace files of 4096 bytes and will create new ones as long as |
508 | there is data available. | |
05be3802 MD |
509 | .RE |
510 | .PP | |
6991b181 | 511 | |
6a240cd9 MD |
512 | .PP |
513 | \fBenable-event\fP NAME[,NAME2,...] [-k|-u] [OPTIONS] | |
514 | .RS | |
6991b181 DG |
515 | Enable tracing event |
516 | ||
c9e32613 | 517 | A tracing event is always assigned to a channel. If \fB\-c, \-\-channel\fP is |
6991b181 | 518 | omitted, a default channel named '\fBchannel0\fP' is created and the event is |
85076754 MD |
519 | added to it. If \fB\-c, \-\-channel\fP is omitted, but a non-default |
520 | channel already exists within the session, an error is returned. For the | |
521 | user-space tracer, using \fB\-a, \-\-all\fP is the same as using the | |
522 | wildcard "*". | |
6991b181 | 523 | |
c9e32613 | 524 | If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc |
6991b181 | 525 | file. |
6991b181 DG |
526 | |
527 | .B OPTIONS: | |
528 | ||
6a240cd9 MD |
529 | .TP |
530 | .BR "\-h, \-\-help" | |
531 | Show summary of possible options and commands. | |
532 | .TP | |
533 | .BR "\-\-list-options" | |
534 | Simple listing of options | |
535 | .TP | |
536 | .BR "\-s, \-\-session NAME" | |
537 | Apply on session name | |
538 | .TP | |
539 | .BR "\-c, \-\-channel NAME" | |
540 | Apply on channel name | |
541 | .TP | |
542 | .BR "\-a, \-\-all" | |
e256d661 | 543 | Enable all tracepoints and syscalls. This actually enables a single |
6a240cd9 MD |
544 | wildcard event "*". |
545 | .TP | |
546 | .BR "\-k, \-\-kernel" | |
547 | Apply for the kernel tracer | |
548 | .TP | |
549 | .BR "\-u, \-\-userspace" | |
550 | Apply for the user-space tracer | |
551 | .TP | |
bed69e7d DG |
552 | .BR "\-j, \-\-jul" |
553 | Apply for Java application using Java Util Logging interface (JUL) | |
554 | .TP | |
222e4eab DG |
555 | .BR "\-l, \-\-log4j" |
556 | Apply for Java application using LOG4J | |
557 | .TP | |
0e115563 DG |
558 | .BR "\-p, \-\-python" |
559 | Apply for Python application using the logging module. | |
560 | .TP | |
6a240cd9 | 561 | .BR "\-\-tracepoint" |
e256d661 | 562 | Tracepoint event (default). Userspace tracer supports wildcards at the end |
6a240cd9 MD |
563 | of string. Don't forget to quote to deal with bash expansion. |
564 | e.g.: | |
6991b181 | 565 | .nf |
6991b181 DG |
566 | "*" |
567 | "app_component:na*" | |
6991b181 | 568 | .fi |
6a240cd9 MD |
569 | .TP |
570 | .BR "\-\-loglevel NAME" | |
571 | Tracepoint loglevel range from 0 to loglevel. Listed in the help (\-h). | |
f9e8873b DG |
572 | For the JUL domain, the loglevel ranges are detailed with the \-\-help |
573 | option thus starting from SEVERE to FINEST. | |
999ee001 DG |
574 | For the LOG4J domain, loglevels range from FATAL to TRACE which are also |
575 | detailed in the help. | |
0e115563 DG |
576 | For the Python domain, loglevels range from CRITICAL to DEBUG which are |
577 | detailed in the help as well. | |
6a240cd9 MD |
578 | .TP |
579 | .BR "\-\-loglevel-only NAME" | |
580 | Tracepoint loglevel (only this loglevel). | |
581 | The loglevel or loglevel-only options should be combined with a | |
582 | tracepoint name or tracepoint wildcard. | |
583 | .TP | |
584 | .BR "\-\-probe (addr | symbol | symbol+offset)" | |
585 | Dynamic probe. Addr and offset can be octal (0NNN...), decimal (NNN...) | |
586 | or hexadecimal (0xNNN...) | |
587 | .TP | |
588 | .BR "\-\-function (addr | symbol | symbol+offset)" | |
589 | Dynamic function entry/return probe. Addr and offset can be octal | |
590 | (0NNN...), decimal (NNN...) or hexadecimal (0xNNN...) | |
591 | .TP | |
592 | .BR "\-\-syscall" | |
593 | System call event. Enabling syscalls tracing (kernel tracer), you will | |
594 | not be able to disable them with disable-event. This is a known | |
627dbfd8 CB |
595 | limitation. You can disable the entire channel to do the trick. Also note |
596 | that per-syscall selection is not supported yet. Use with "-a" to enable | |
597 | all syscalls. | |
6a240cd9 MD |
598 | .TP |
599 | .BR "\-\-filter 'expression'" | |
600 | Set a filter on a newly enabled event. Filter expression on event | |
e256d661 JG |
601 | fields and context. The event will be recorded if the filter's |
602 | expression evaluates to TRUE. Only specify on first activation of a | |
603 | given event within a session. | |
604 | Specifying a filter is only allowed when enabling events within a session before | |
6a240cd9 MD |
605 | tracing is started. If the filter fails to link with the event |
606 | within the traced domain, the event will be discarded. | |
e256d661 | 607 | Filtering is currently only implemented for the user-space tracer. |
6a240cd9 MD |
608 | |
609 | Expression examples: | |
610 | ||
611 | .nf | |
612 | 'intfield > 500 && intfield < 503' | |
613 | '(strfield == "test" || intfield != 10) && intfield > 33' | |
614 | 'doublefield > 1.1 && intfield < 5.3' | |
615 | .fi | |
616 | ||
617 | Wildcards are allowed at the end of strings: | |
618 | 'seqfield1 == "te*"' | |
619 | In string literals, the escape character is a '\\'. Use '\\*' for | |
e256d661 JG |
620 | the '*' character, and '\\\\' for the '\\' character sequence. Wildcard |
621 | matches any sequence of characters, including an empty sub-string | |
622 | (matches 0 or more characters). | |
6a240cd9 | 623 | |
e256d661 JG |
624 | Context information can be used for filtering. The examples below shows |
625 | usage of context filtering on the process name (using a wildcard), process ID | |
626 | range, and unique thread ID. The process and thread IDs of | |
6a240cd9 MD |
627 | running applications can be found under columns "PID" and "LWP" of the |
628 | "ps -eLf" command. | |
629 | ||
630 | .nf | |
631 | '$ctx.procname == "demo*"' | |
632 | '$ctx.vpid >= 4433 && $ctx.vpid < 4455' | |
633 | '$ctx.vtid == 1234' | |
634 | .fi | |
635 | ||
11139b74 DG |
636 | Context information is available to all filters whether or not the add-context |
637 | command has been used to add it to the event's channel, as long as the context | |
638 | field exists for that domain. For example, the filter examples given above will | |
639 | never fail to link: no add-context is required for the event's channel. | |
640 | ||
bccd20a3 JI |
641 | .TP |
642 | .BR "\-x, \-\-exclude LIST" | |
643 | Add exclusions to UST tracepoints: | |
644 | Events that match any of the items in the comma-separated LIST are not | |
645 | enabled, even if they match a wildcard definition of the event. | |
646 | ||
647 | This option is also applicable with the \fB\-a, \-\-all\fP option, | |
648 | in which case all UST tracepoints are enabled except the ones whose | |
649 | names match any of the items in LIST. | |
6a240cd9 MD |
650 | .RE |
651 | .PP | |
6991b181 | 652 | |
272c6a17 MD |
653 | .PP |
654 | \fBdisable-channel\fP NAME[,NAME2,...] (\-k | \-u) [OPTIONS] | |
655 | .RS | |
6991b181 DG |
656 | Disable tracing channel |
657 | ||
e256d661 | 658 | Disabling a channel disables the tracing of all of the channel's events. A channel |
5368d366 | 659 | can be re-enabled by calling \fBlttng enable-channel NAME\fP again. |
6991b181 | 660 | |
c9e32613 | 661 | If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc |
6991b181 | 662 | file. |
6991b181 DG |
663 | |
664 | .B OPTIONS: | |
665 | ||
272c6a17 MD |
666 | .TP |
667 | .BR "\-h, \-\-help" | |
668 | Show summary of possible options and commands. | |
669 | .TP | |
670 | .BR "\-\-list-options" | |
671 | Simple listing of options | |
672 | .TP | |
673 | .BR "\-s, \-\-session NAME" | |
674 | Apply on session name | |
675 | .TP | |
676 | .BR "\-k, \-\-kernel" | |
677 | Apply for the kernel tracer | |
678 | .TP | |
679 | .BR "\-u, \-\-userspace" | |
680 | Apply for the user-space tracer | |
681 | .RE | |
682 | .PP | |
6991b181 | 683 | |
c138a39b MD |
684 | .PP |
685 | \fBdisable-event\fP NAME[,NAME2,...] (\-k | \-u) [OPTIONS] | |
686 | .RS | |
6991b181 DG |
687 | Disable tracing event |
688 | ||
689 | The event, once disabled, can be re-enabled by calling \fBlttng enable-event | |
690 | NAME\fP again. | |
691 | ||
c9e32613 | 692 | If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc |
6991b181 | 693 | file. |
6991b181 | 694 | |
85076754 MD |
695 | If \fB\-c, \-\-channel\fP is omitted, the default channel name is used. |
696 | If \fB\-c, \-\-channel\fP is omitted, but a non-default channel already | |
697 | exists within the session, an error is returned. | |
698 | ||
6991b181 DG |
699 | .B OPTIONS: |
700 | ||
c138a39b MD |
701 | .TP |
702 | .BR "\-h, \-\-help" | |
703 | Show summary of possible options and commands. | |
704 | .TP | |
705 | .BR "\-\-list-options" | |
706 | Simple listing of options | |
707 | .TP | |
708 | .BR "\-s, \-\-session NAME" | |
709 | Apply on session name | |
710 | .TP | |
85076754 MD |
711 | .BR "\-c, \-\-channel NAME" |
712 | Apply on channel name | |
713 | .TP | |
c138a39b MD |
714 | .BR "\-a, \-\-all-events" |
715 | Disable all events. This does NOT disable "*" but rather every known | |
716 | events of the session. | |
717 | .TP | |
718 | .BR "\-k, \-\-kernel" | |
719 | Apply for the kernel tracer | |
720 | .TP | |
721 | .BR "\-u, \-\-userspace" | |
722 | Apply for the user-space tracer | |
bed69e7d DG |
723 | .TP |
724 | .BR "\-j, \-\-jul" | |
725 | Apply for Java application using Java Util Logging interface (JUL) | |
222e4eab DG |
726 | .TP |
727 | .BR "\-l, \-\-log4j" | |
728 | Apply for Java application using LOG4J | |
0e115563 DG |
729 | .TP |
730 | .BR "\-p, \-\-python" | |
731 | Apply for Python application using the logging module. | |
c138a39b MD |
732 | .RE |
733 | .PP | |
6991b181 | 734 | |
747361fe MD |
735 | .PP |
736 | \fBlist\fP [OPTIONS] [SESSION [SESSION OPTIONS]] | |
737 | .RS | |
c9e32613 | 738 | List tracing session information. |
6991b181 DG |
739 | |
740 | With no arguments, it will list available tracing session(s). | |
741 | ||
fa072eae YB |
742 | With the session name, it will display the details of the session including |
743 | the trace file path, the associated channels and their state (activated | |
d829b38c | 744 | and deactivated), the activated events and more. |
fa072eae | 745 | |
c9e32613 | 746 | With \-k alone, it will list all available kernel events (except the system |
6991b181 | 747 | calls events). |
bed69e7d DG |
748 | With \-j alone, the available JUL event from registered application will be |
749 | list. The event corresponds to the Logger name in the Java JUL application. | |
999ee001 DG |
750 | With \-l alone, the available LOG4J event from registered application will be |
751 | list. The event corresponds to the Logger name in the Java LOG4J application. | |
0e115563 DG |
752 | With \-p alone, the available Python event from registered application will be |
753 | list. The event corresponds to the Logger name in the Python application. | |
c9e32613 DG |
754 | With \-u alone, it will list all available user-space events from registered |
755 | applications. Here is an example of 'lttng list \-u': | |
6991b181 | 756 | |
747361fe | 757 | .nf |
6991b181 DG |
758 | PID: 7448 - Name: /tmp/lttng-ust/tests/hello/.libs/lt-hello |
759 | ust_tests_hello:tptest_sighandler (type: tracepoint) | |
760 | ust_tests_hello:tptest (type: tracepoint) | |
747361fe | 761 | .fi |
6991b181 DG |
762 | |
763 | You can now enable any event listed by using the name : | |
764 | \fBust_tests_hello:tptest\fP. | |
6991b181 DG |
765 | |
766 | .B OPTIONS: | |
767 | ||
747361fe MD |
768 | .TP |
769 | .BR "\-h, \-\-help" | |
770 | Show summary of possible options and commands. | |
771 | .TP | |
772 | .BR "\-\-list-options" | |
773 | Simple listing of options | |
774 | .TP | |
775 | .BR "\-k, \-\-kernel" | |
776 | Select kernel domain | |
777 | .TP | |
778 | .BR "\-u, \-\-userspace" | |
779 | Select user-space domain. | |
bed69e7d DG |
780 | .TP |
781 | .BR "\-j, \-\-jul" | |
782 | Apply for Java application using JUL | |
783 | .TP | |
222e4eab DG |
784 | .BR "\-l, \-\-log4j" |
785 | Apply for Java application using LOG4J | |
0e115563 DG |
786 | .TP |
787 | .BR "\-p, \-\-python" | |
788 | Apply for Python application using the logging module. | |
789 | .TP | |
bed69e7d DG |
790 | .BR "\-f, \-\-fields" |
791 | List event fields | |
6991b181 | 792 | |
747361fe | 793 | .PP |
6b8f2e64 DG |
794 | .B SESSION OPTIONS: |
795 | ||
747361fe MD |
796 | .TP |
797 | .BR "\-c, \-\-channel NAME" | |
798 | List details of a channel | |
799 | .TP | |
800 | .BR "\-d, \-\-domain" | |
801 | List available domain(s) | |
802 | .RE | |
803 | .PP | |
6991b181 | 804 | |
516f6cbe JG |
805 | .PP |
806 | \fBload\fP [OPTIONS] [NAME] | |
807 | .RS | |
808 | Load tracing session configuration | |
809 | ||
810 | If NAME is omitted, all session configurations found in both the user's session | |
bd88d988 | 811 | configuration directory (default: ~/.lttng/sessions/) and the system session |
cf53c06d DG |
812 | configuration directory (default: /etc/lttng/sessions/) will be loaded. Note |
813 | that the sessions in the user directory are loaded first and then the system | |
814 | wide directory are loaded. | |
516f6cbe JG |
815 | |
816 | .B OPTIONS: | |
817 | ||
818 | .TP | |
819 | .BR "\-h, \-\-help" | |
820 | Show summary of possible options and commands. | |
821 | .TP | |
822 | .BR "\-a, \-\-all" | |
823 | Load all session configurations (default). | |
824 | .TP | |
825 | .BR "\-i, \-\-input-path PATH" | |
bd88d988 DG |
826 | Specify the input path for session configurations. This overrides the default |
827 | session configuration directory. | |
516f6cbe JG |
828 | .TP |
829 | .BR "\-f, -\-force" | |
830 | Overwrite current session configuration(s) if a session of the same name | |
831 | already exists. | |
832 | .RE | |
833 | .PP | |
834 | ||
835 | .PP | |
836 | \fBsave\fP [OPTIONS] [SESSION] | |
837 | .RS | |
838 | Save tracing session configuration | |
839 | ||
840 | If SESSION is omitted, all session configurations will be saved to individual | |
553067af | 841 | \fB.lttng\fP files under the user's session configuration directory (default: |
bd88d988 DG |
842 | ~/.lttng/sessions/). The default session configuration file naming scheme is |
843 | \fBSESSION.lttng\fP. | |
516f6cbe | 844 | |
cf53c06d DG |
845 | For instance, a user in the tracing group saving a session from a root session |
846 | daemon will save it in her/his user directory. | |
847 | ||
516f6cbe JG |
848 | .B OPTIONS: |
849 | ||
850 | .TP | |
851 | .BR "\-h, \-\-help" | |
852 | Show summary of possible options and commands. | |
853 | .TP | |
854 | .BR "\-a, \-\-all" | |
855 | Save all session configurations (default). | |
856 | .TP | |
857 | .BR "\-o, \-\-output-path PATH" | |
553067af DG |
858 | Specify the output path for saved sessions. This overrides the default session |
859 | configuration directory. | |
516f6cbe JG |
860 | .TP |
861 | .BR "\-f, -\-force" | |
862 | Overwrite session configuration file if session name clashes. | |
863 | .RE | |
864 | .PP | |
865 | ||
7c96a096 MD |
866 | .PP |
867 | \fBset-session\fP NAME [OPTIONS] | |
868 | .RS | |
6991b181 DG |
869 | Set current session name |
870 | ||
871 | Will change the session name in the .lttngrc file. | |
6991b181 DG |
872 | |
873 | .B OPTIONS: | |
874 | ||
7c96a096 MD |
875 | .TP |
876 | .BR "\-h, \-\-help" | |
877 | Show summary of possible options and commands. | |
878 | .TP | |
879 | .BR "\-\-list-options" | |
880 | Simple listing of options | |
881 | .RE | |
882 | .PP | |
6991b181 | 883 | |
8df3bfe9 MD |
884 | .PP |
885 | \fBsnapshot\fP [OPTIONS] ACTION | |
886 | .RS | |
b872baea | 887 | Snapshot command for LTTng session. |
b872baea DG |
888 | |
889 | .B OPTIONS: | |
890 | ||
8df3bfe9 MD |
891 | .TP |
892 | .BR "\-h, \-\-help" | |
893 | Show summary of possible options and commands. | |
894 | .TP | |
895 | .BR "\-\-list-options" | |
896 | Simple listing of options | |
b872baea | 897 | |
8df3bfe9 | 898 | .PP |
b872baea DG |
899 | .B ACTION: |
900 | ||
8df3bfe9 | 901 | .TP |
b872baea DG |
902 | \fBadd-output\fP [-m <SIZE>] [-s <NAME>] [-n <NAME>] <URL> | -C <URL> -D <URL> |
903 | ||
88743287 | 904 | Setup and add a snapshot output for a session. Output is the destination |
b872baea DG |
905 | where the snapshot will be sent. Only one output is permitted. To change it, |
906 | you'll need to delete it and add back the new one. | |
907 | ||
8df3bfe9 | 908 | .TP |
b872baea DG |
909 | \fBdel-output\fP ID | NAME [-s <NAME>] |
910 | ||
88743287 JG |
911 | Delete an output for a session using the output's ID. You can either specify the |
912 | output by name or use its ID as returned by the list-output command. | |
b872baea | 913 | |
8df3bfe9 | 914 | .TP |
b872baea DG |
915 | \fBlist-output\fP [-s <NAME>] |
916 | ||
917 | List the output of a session. Attributes of the output are printed. | |
918 | ||
8df3bfe9 | 919 | .TP |
b872baea DG |
920 | \fBrecord\fP [-m <SIZE>] [-s <NAME>] [-n <NAME>] [<URL> | -C <URL> -D <URL>] |
921 | ||
922 | Snapshot a session's buffer(s) for all domains. If an URL is specified, it is | |
923 | used instead of a previously added output. Specifying only a name or/and a max | |
924 | size will override the current output values. For instance, you can record a | |
925 | snapshot with a custom maximum size or with a different name. | |
926 | ||
8df3bfe9 | 927 | .nf |
1ac1098f | 928 | $ lttng snapshot add-output -n mysnapshot file:///data/snapshot |
b872baea DG |
929 | [...] |
930 | $ lttng snapshot record -n new_name_snapshot | |
8df3bfe9 | 931 | .fi |
b872baea DG |
932 | |
933 | The above will create a snapshot in /data/snapshot/new_name_snapshot* directory | |
934 | rather then in mysnapshot*/ | |
b872baea | 935 | |
8df3bfe9 MD |
936 | .PP |
937 | .B DETAILED ACTION OPTIONS | |
b872baea | 938 | |
8df3bfe9 MD |
939 | .TP |
940 | .BR "\-s, \-\-session NAME" | |
941 | Apply to session name. | |
942 | .TP | |
943 | .BR "\-n, \-\-name NAME" | |
944 | Name of the snapshot's output. | |
945 | .TP | |
946 | .BR "\-m, \-\-max-size SIZE" | |
eb82f91d | 947 | Maximum size in bytes of the snapshot. The maximum size does not include the |
a8f307d8 SM |
948 | metadata file. Human readable format is accepted: {+k,+M,+G}. For instance, |
949 | \-\-max-size 5M | |
8df3bfe9 MD |
950 | .TP |
951 | .BR "\-C, \-\-ctrl-url URL" | |
952 | Set control path URL. (Must use -D also) | |
953 | .TP | |
954 | .BR "\-D, \-\-data-url URL" | |
955 | Set data path URL. (Must use -C also) | |
956 | .RE | |
957 | .PP | |
b872baea | 958 | |
afb8ca1b MD |
959 | .PP |
960 | \fBstart\fP [NAME] [OPTIONS] | |
961 | .RS | |
6991b181 DG |
962 | Start tracing |
963 | ||
964 | It will start tracing for all tracers for a specific tracing session. | |
6991b181 | 965 | If NAME is omitted, the session name is taken from the .lttngrc file. |
6991b181 DG |
966 | |
967 | .B OPTIONS: | |
968 | ||
afb8ca1b MD |
969 | .TP |
970 | .BR "\-h, \-\-help" | |
971 | Show summary of possible options and commands. | |
972 | .TP | |
973 | .BR "\-\-list-options" | |
974 | Simple listing of options | |
975 | .RE | |
976 | .PP | |
6991b181 | 977 | |
6c09bfdb MD |
978 | .PP |
979 | \fBstop\fP [NAME] [OPTIONS] | |
980 | .RS | |
6991b181 DG |
981 | Stop tracing |
982 | ||
391b9c72 DG |
983 | It will stop tracing for all tracers for a specific tracing session. Before |
984 | returning, the command checks for data availability meaning that it will wait | |
985 | until the trace is readable for the session. Use \-\-no-wait to avoid this | |
986 | behavior. | |
6991b181 DG |
987 | |
988 | If NAME is omitted, the session name is taken from the .lttngrc file. | |
6991b181 DG |
989 | |
990 | .B OPTIONS: | |
991 | ||
6c09bfdb MD |
992 | .TP |
993 | .BR "\-h, \-\-help" | |
994 | Show summary of possible options and commands. | |
995 | .TP | |
996 | .BR "\-\-list-options" | |
997 | Simple listing of options | |
3a7a166e MJ |
998 | .TP |
999 | .BR "\-\-no-wait" | |
6c09bfdb MD |
1000 | Don't wait for data availability. |
1001 | .RE | |
1002 | .PP | |
6991b181 | 1003 | |
5975c30a MD |
1004 | .PP |
1005 | \fBversion\fP | |
1006 | .RS | |
6991b181 | 1007 | Show version information |
6991b181 DG |
1008 | |
1009 | .B OPTIONS: | |
1010 | ||
5975c30a MD |
1011 | .TP |
1012 | .BR "\-h, \-\-help" | |
1013 | Show summary of possible options and commands. | |
1014 | .TP | |
1015 | .BR "\-\-list-options" | |
1016 | Simple listing of options | |
1017 | .RE | |
1018 | .PP | |
6991b181 | 1019 | |
5b4c1410 MD |
1020 | .PP |
1021 | \fBview\fP [SESSION_NAME] [OPTIONS] | |
1022 | .RS | |
1023 | View traces of a tracing session. By default, the babeltrace viewer | |
1024 | will be used for text viewing. If SESSION_NAME is omitted, the session | |
1025 | name is taken from the .lttngrc file. | |
6991b181 DG |
1026 | |
1027 | .B OPTIONS: | |
1028 | ||
5b4c1410 MD |
1029 | .TP |
1030 | .BR "\-h, \-\-help" | |
1031 | Show this help | |
1032 | .TP | |
1033 | .BR "\-\-list-options" | |
1034 | Simple listing of options | |
1035 | .TP | |
1036 | .BR "\-t, \-\-trace-path PATH" | |
1037 | Trace directory path for the viewer | |
1038 | .TP | |
1039 | .BR "\-e, \-\-viewer CMD" | |
1040 | Specify viewer and/or options to use This will completely override the | |
1041 | default viewers so please make sure to specify the full command. The | |
1042 | trace directory path of the session will be appended at the end to the | |
1043 | arguments | |
1044 | .RE | |
1045 | .PP | |
6991b181 | 1046 | |
999ee001 DG |
1047 | .SH "JUL/LOG4J DOMAIN" |
1048 | ||
1049 | This section explains the JUL and LOG4J domain where JUL stands for Java Util | |
1050 | Logging. You can use these by using the \fBliblttng-ust-<domain>-jni.so\fP from | |
1051 | the lttng-ust(3) project. | |
acf47627 DG |
1052 | |
1053 | The LTTng Java Agent uses JNI to link the UST tracer to the Java application | |
1054 | that uses the agent. Thus, it behaves similarly to the UST domain (\-u). When | |
999ee001 DG |
1055 | enabling events, you enable a Logger name that will then be mapped to a default |
1056 | UST tracepoint called \fBlttng_jul:<domain>_event\fP in the | |
1057 | \fBlttng_<domain>_channel\fP. Using the lttng-ctl API, any JUL/LOG4J events | |
1058 | must use the tracepoint event type (same as \-\-tracepoint). | |
acf47627 | 1059 | |
999ee001 DG |
1060 | Because of the default immutable channel, the \fBenable-channel\fP command CAN |
1061 | NOT be used with the JUL and LOG4J domain thus not having any options. | |
acf47627 | 1062 | |
999ee001 DG |
1063 | Also, loglevels are supported. Use \fBlttng enable-event \-h\fP to list them. |
1064 | Wildcards are NOT supported except the "*" meaning all events (same as \-a). | |
acf47627 DG |
1065 | |
1066 | Exactly like the UST domain, if the Java application has the same UID as you, | |
1067 | you can trace it. Same goes for the tracing group accessing root applications. | |
1068 | ||
999ee001 DG |
1069 | Finally, you can list every Logger name that are available from registered |
1070 | applications to the session daemon by using \fBlttng list \-j\fP or \fB\-l\fP. | |
acf47627 | 1071 | |
999ee001 | 1072 | Here is an example on how to use the JUL domain. |
acf47627 DG |
1073 | |
1074 | .nf | |
1075 | $ lttng list -j | |
1076 | [...] | |
1077 | $ lttng create aSession | |
1078 | $ lttng enable-event -s aSession -j MyCustomLoggerName | |
1079 | $ lttng start | |
1080 | .fi | |
1081 | ||
1082 | More information can be found in the lttng-ust documentation, see | |
1083 | java-util-logging.txt | |
1084 | .PP | |
1085 | ||
c206d957 | 1086 | .SH "EXIT VALUES" |
b107a0b1 | 1087 | .PP |
6b8f2e64 DG |
1088 | On success 0 is returned and a positive value on error. Value of 1 means a command |
1089 | error, 2 an undefined command, 3 a fatal error and 4 a command warning meaning that | |
1090 | something went wrong during the command. | |
c206d957 | 1091 | |
6b8f2e64 | 1092 | Any other value above 10, please refer to |
b107a0b1 | 1093 | .BR "<lttng/lttng-error.h>" |
6b8f2e64 DG |
1094 | for a detailed list or use lttng_strerror() to get a human readable string of |
1095 | the error code. | |
c206d957 | 1096 | .PP |
b107a0b1 | 1097 | |
6991b181 DG |
1098 | .SH "ENVIRONMENT VARIABLES" |
1099 | ||
1100 | .PP | |
1101 | Note that all command line options override environment variables. | |
1102 | .PP | |
1103 | ||
1104 | .PP | |
05833633 | 1105 | .IP "LTTNG_SESSIOND_PATH" |
c9e32613 DG |
1106 | Allows one to specify the full session daemon binary path to lttng command line |
1107 | tool. You can also use \-\-sessiond-path option having the same effect. | |
b107a0b1 MD |
1108 | .PP |
1109 | ||
516f6cbe JG |
1110 | .PP |
1111 | .IP "LTTNG_SESSION_CONFIG_XSD_PATH" | |
1112 | Set the path in which the \fBsession.xsd\fP session configuration schema may be | |
1113 | found. | |
1114 | .PP | |
1115 | ||
6991b181 | 1116 | .SH "SEE ALSO" |
6b8f2e64 DG |
1117 | .BR babeltrace(1), |
1118 | .BR lttng-ust(3), | |
1119 | .BR lttng-sessiond(8), | |
1120 | .BR lttng-relayd(8), | |
464bd4b0 | 1121 | .BR lttng-crash(1), |
b107a0b1 | 1122 | |
6991b181 DG |
1123 | .SH "BUGS" |
1124 | ||
b107a0b1 | 1125 | .PP |
6991b181 | 1126 | If you encounter any issues or usability problem, please report it on our |
6b8f2e64 | 1127 | mailing list <lttng-dev@lists.lttng.org> to help improve this project or |
eb82f91d | 1128 | at https://bugs.lttng.org which is a bug tracker. |
b107a0b1 MD |
1129 | .PP |
1130 | ||
6991b181 DG |
1131 | .SH "CREDITS" |
1132 | ||
1133 | .PP | |
c9e32613 | 1134 | lttng is distributed under the GNU General Public License version 2. See the file |
6991b181 DG |
1135 | COPYING for details. |
1136 | .PP | |
1137 | A Web site is available at http://lttng.org for more information on the LTTng | |
1138 | project. | |
1139 | .PP | |
1140 | You can also find our git tree at http://git.lttng.org. | |
1141 | .PP | |
1142 | Mailing lists for support and development: <lttng-dev@lists.lttng.org>. | |
1143 | .PP | |
1144 | You can find us on IRC server irc.oftc.net (OFTC) in #lttng. | |
1145 | .PP | |
1146 | .SH "THANKS" | |
1147 | ||
1148 | .PP | |
1149 | Thanks to Yannick Brosseau without whom this project would never have been so | |
1150 | lean and mean! Also thanks to the Ericsson teams working on tracing which | |
fa072eae | 1151 | helped us greatly with detailed bug reports and unusual test cases. |
6991b181 DG |
1152 | |
1153 | Thanks to our beloved packager Alexandre Montplaisir-Goncalves (Ubuntu and PPA | |
1154 | maintainer) and Jon Bernard for our Debian packages. | |
1155 | ||
1156 | Special thanks to Michel Dagenais and the DORSAL laboratory at Polytechnique de | |
1157 | Montreal for the LTTng journey. | |
c9e32613 | 1158 | .PP |
6991b181 DG |
1159 | .SH "AUTHORS" |
1160 | ||
1161 | .PP | |
1162 | lttng-tools was originally written by Mathieu Desnoyers, Julien Desfossez and | |
1163 | David Goulet. More people have since contributed to it. It is currently | |
9b22d135 | 1164 | maintained by Jérémie Galarneau <jeremie.galarneau@efficios.com>. |
6991b181 | 1165 | .PP |