X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=doc%2Fman%2Flttng.1;h=1475068c56f740194e1b2d161e3cc7df6ec9d0ca;hp=483d60ccce87810b4c664c6d8c283cced51c1ea8;hb=553067af0eedeae7dccfa7c83b5a68335a088b75;hpb=274d6c5de5f7fc9374da1932a6a4b1f0ee654a65 diff --git a/doc/man/lttng.1 b/doc/man/lttng.1 index 483d60ccc..1475068c5 100644 --- a/doc/man/lttng.1 +++ b/doc/man/lttng.1 @@ -1,4 +1,4 @@ -.TH "LTTNG" "1" "February 05th, 2014" "" "" +.TH "LTTNG" "1" "May 13th, 2014" "" "" .SH "NAME" lttng \(em LTTng 2.x tracer control command line tool @@ -87,20 +87,25 @@ Add context to event(s) and/or channel(s). A context is basically extra information appended to a channel. For instance, you could ask the tracer to add the PID information for all events in a channel. You can also add performance monitoring unit counters (perf PMU) using -the perf kernel API). +the perf kernel API. -For example, this command will add the context information 'prio' and two perf -counters (hardware branch misses and cache misses), to all events in the trace +For example, this command will add the context information 'prio' and two per-CPU +perf counters (hardware branch misses and cache misses), to all events in the trace data output: .nf -# lttng add-context \-k \-t prio \-t perf:branch-misses \\ - \-t perf:cache-misses +# lttng add-context \-k \-t prio \-t perf:cpu:branch-misses \\ + \-t perf:cpu:cache-misses .fi Please take a look at the help (\-h/\-\-help) for a detailed list of available contexts. +Perf counters are available as per-CPU ("perf:cpu:...") and per-thread +("perf:thread:...") counters. Currently, per-CPU counters can only be +used with the kernel tracing domain, and per-thread counters can only be +used with the UST tracing domain. + If no channel is given (\-c), the context is added to all channels that were already enabled. If the session has no channel, a default channel is created. Otherwise the context will be added only to the given channel (\-c). @@ -160,9 +165,9 @@ 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 add-context \-\-kernel \-t perf:cpu:LLC-load-misses \\ + \-t perf:cpu:LLC-store-misses \\ + \-t perf:cpu:LLC-prefetch-misses # lttng start # for a in $(seq 1 10); do \\ lttng calibrate \-\-kernel \-\-function; @@ -397,7 +402,8 @@ Apply to the user-space tracer Discard event when subbuffers are full (default) .TP .BR "\-\-overwrite" -Flight recorder mode : overwrites events when subbuffers are full +Flight recorder mode: overwrites events when subbuffers are full. The +number of subbuffer must be 2 or more. .TP .BR "\-\-subbuf-size SIZE" Subbuffer size in bytes {+k,+M,+G}. @@ -437,6 +443,8 @@ Use shared buffer for the whole system (\-k only) .BR "\-C, \-\-tracefile-size SIZE" Maximum size of each tracefile within a stream (in bytes). 0 means unlimited. (default: 0) +Note: traces generated with this option may inaccurately report +discarded events as of CTF 1.8. .TP .BR "\-W, \-\-tracefile-count COUNT" Used in conjunction with \-C option, this will limit the number of files @@ -541,7 +549,9 @@ Dynamic function entry/return probe. Addr and offset can be octal .BR "\-\-syscall" System call event. Enabling syscalls tracing (kernel tracer), you will not be able to disable them with disable-event. This is a known -limitation. You can disable the entire channel to do the trick. +limitation. You can disable the entire channel to do the trick. Also note +that per-syscall selection is not supported yet. Use with "-a" to enable +all syscalls. .TP .BR "\-\-filter 'expression'" Set a filter on a newly enabled event. Filter expression on event @@ -580,6 +590,11 @@ running applications can be found under columns "PID" and "LWP" of the '$ctx.vtid == 1234' .fi +Context information is available to all filters whether or not the add-context +command has been used to add it to the event's channel, as long as the context +field exists for that domain. For example, the filter examples given above will +never fail to link: no add-context is required for the event's channel. + .TP .BR "\-x, \-\-exclude LIST" Add exclusions to UST tracepoints: @@ -598,7 +613,7 @@ names match any of the items in LIST. Disable tracing channel Disabling a channel disables the tracing of all of the channel's events. A channel -can be reenabled by calling \fBlttng enable-channel NAME\fP again. +can be re-enabled by calling \fBlttng enable-channel NAME\fP again. If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc file. @@ -728,6 +743,61 @@ List available domain(s) .RE .PP +.PP +\fBload\fP [OPTIONS] [NAME] +.RS +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. + +.B OPTIONS: + +.TP +.BR "\-h, \-\-help" +Show summary of possible options and commands. +.TP +.BR "\-a, \-\-all" +Load all session configurations (default). +.TP +.BR "\-i, \-\-input-path PATH" +Specify the input path for session configurations. +.TP +.BR "\-f, -\-force" +Overwrite current session configuration(s) if a session of the same name +already exists. +.RE +.PP + +.PP +\fBsave\fP [OPTIONS] [SESSION] +.RS +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 (default: +~/.lttng/sessions/ or /var/run/lttng/sessions/ for root user). The default +session configuration file naming scheme is \fBSESSION.lttng\fP. + +.B OPTIONS: + +.TP +.BR "\-h, \-\-help" +Show summary of possible options and commands. +.TP +.BR "\-a, \-\-all" +Save all session configurations (default). +.TP +.BR "\-o, \-\-output-path PATH" +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. +.RE +.PP + .PP \fBset-session\fP NAME [OPTIONS] .RS @@ -812,6 +882,10 @@ Name of the snapshot's output. Maximum size in bytes of the snapshot. The maxium size does not include the metadata file. Human readable format is accepted: {+k,+M,+G}. For instance, \-\-max-size 5M + +The minimum size of a snapshot is computed by multiplying the total amount of +streams in the session by the largest subbuffer size. This is to ensure +fairness between channels when extracting data. .TP .BR "\-C, \-\-ctrl-url URL" Set control path URL. (Must use -D also) @@ -860,7 +934,8 @@ Show summary of possible options and commands. .TP .BR "\-\-list-options" Simple listing of options -.TP "\-\-no-wait" +.TP +.BR "\-\-no-wait" Don't wait for data availability. .RE .PP @@ -972,6 +1047,12 @@ 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. .PP +.PP +.IP "LTTNG_SESSION_CONFIG_XSD_PATH" +Set the path in which the \fBsession.xsd\fP session configuration schema may be +found. +.PP + .SH "SEE ALSO" .BR babeltrace(1), .BR lttng-ust(3),