Fix: clarify session conf. directory in man

[lttng-tools.git] / doc / man / lttng.1

diff --git a/doc/man/lttng.1 b/doc/man/lttng.1
index 627ab9c9530c7a82bfd36382fc26f850e50734d2..1475068c56f740194e1b2d161e3cc7df6ec9d0ca 100644 (file)
--- a/doc/man/lttng.1
+++ b/doc/man/lttng.1
@@ -402,7 +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}.
@@ -442,6 +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
@@ -773,8 +776,9 @@ already exists.
 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/ or /var/run/lttng/sessions/ for root user). The default
+session configuration file naming scheme is \fBSESSION.lttng\fP.
 
 .B OPTIONS:
 
@@ -786,7 +790,8 @@ Show summary of possible options and commands.
 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.
@@ -877,6 +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)