X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=doc%2Fman%2Flttng.1;h=e650d24264c27e50b65d59973c26c5935fc69e4f;hb=cea28771668f6fd337d00466ea9f01c12cda7467;hp=26fd44a69db986148a9b7150868a721b8ca8f4b1;hpb=feb0f3e5900ff58202ea0c3f227de3c1b8291952;p=lttng-tools.git

diff --git a/doc/man/lttng.1 b/doc/man/lttng.1
index 26fd44a69..e650d2426 100644
--- a/doc/man/lttng.1
+++ b/doc/man/lttng.1
@@ -101,8 +101,9 @@ data output:
 Please take a look at the help (\-h/\-\-help) for a detailed list of available
 contexts.
 
-If no channel is given (\-c), the context is added to all channels. Otherwise
-the context will be added only to the given channel (\-c).
+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).
 
 If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngrc
 file.
@@ -308,8 +309,11 @@ If \fB\-s, \-\-session\fP is omitted, the session name is taken from the .lttngr
 file.
 
 It is important to note that if a certain type of buffers is used, the session
-will be set with that type and all other subsequent channel need to have the
+will be set with that type and all other subsequent channel needs to have the
 same type.
+
+For the kernel tracer (\-k), once the session is started at least once, it's
+not possible anymore to enable new channel for that session.
 .fi
 
 .B OPTIONS:
@@ -334,6 +338,10 @@ same type.
         Subbuffer size in bytes {+k,+M,+G}
         (default UST uid: 131072, UST pid: 4096, kernel: 262144, metadata: 4096)
         Rounded up to the next power of 2.
+
+        The minimum subbuffer size, for each tracer, is the max value between
+        the default above and the system page size. You can issue this command
+        to get the current page size on your system: \fB$ getconf PAGE_SIZE\fP
 \-\-num-subbuf NUM
         Number of subbuffers. (default UST uid: 4, UST pid: 4, kernel: 4, metadata: 2)
         Rounded up to the next power of 2.
@@ -363,8 +371,8 @@ same type.
 .B EXAMPLES:
 
 $ lttng enable-channel -C 4096 -W 32 chan1
-For each stream, the maximum size of a trace file will be 4096 bytes divided
-over a \fBmaximum\fP of 32 different files. The file count is appended after
+For each stream, the maximum size of each trace file will be 4096 bytes, and
+there will be a maximum of 32 different files. The file count is appended after
 the stream number as seen in the following example. The last trace file is
 smaller than 4096 since it was not completely filled.