$
lttng view
lttng-view — Launch an LTTng trace reader
lttng [GENERAL OPTIONS] view [--viewer
=READER
] [SESSION
|--trace-path
=DIR
]
The lttng view
command launches an external trace reader to read the
current traces of:
--session
=SESSION
option
The recording session named SESSION
.
--trace-path
=DIR
option
The local file system directory DIR
.
The current recording session (see concepts(1) to learn more about the current recording session).
With the --session
option or without the --trace-path
option, the mode of the selected recording session may not be network
streaming or live.
By default, the view
command attempts to launch babeltrace2(1) or,
if it’s not available, babeltrace(1). Override which trace reader to
launch with the --viewer
option.
See the “EXAMPLES” section below for usage examples.
See lttng(1) for GENERAL OPTIONS.
-t
DIR
, --trace-path
=DIR
Pass DIR
as the last argument of the trace reader command instead
of the output directory of the selected recording session.
-e
READER
, --viewer
=READER
Use the trace reader READER
to read the traces.
READER
is the absolute path to the reader command to use, and it can
contain command arguments as well. The view
command passes the trace
directory path to read to the READER
command as its last argument.
Without this option, the view
command uses babeltrace2(1) if it’s
available. Otherwise, it tries to use babeltrace(1).
-h
, --help
Show help.
This option attempts to launch /usr/bin/man
to view this manual page.
Override the manual pager path with the LTTNG_MAN_BIN_PATH
environment
variable.
--list-options
List available command options and quit.
Success
Command error
Undefined command
Fatal error
Command warning (something went wrong during the command)
LTTNG_ABORT_ON_ERROR
Set to 1
to abort the process after the first error is
encountered.
LTTNG_HOME
Path to the LTTng home directory.
Defaults to $HOME
.
Useful when the Unix user running the commands has a non-writable home directory.
LTTNG_MAN_BIN_PATH
Absolute path to the manual pager to use to read the LTTng
command-line help (with lttng-help(1) or with the
--help
option) instead of /usr/bin/man
.
LTTNG_SESSION_CONFIG_XSD_PATH
Path to the directory containing the session.xsd
recording session
configuration XML schema.
LTTNG_SESSIOND_PATH
Absolute path to the LTTng session daemon binary (see lttng-sessiond(8)) to spawn from the lttng-create(1) command.
The --sessiond-path
general option overrides this environment
variable.
$LTTNG_HOME/.lttngrc
Unix user’s LTTng runtime configuration.
This is where LTTng stores the name of the Unix user’s current recording session between executions of lttng(1). lttng-create(1) and lttng-set-session(1) set the current recording session.
$LTTNG_HOME/lttng-traces
Default output directory of LTTng traces in local and snapshot modes.
Override this path with the --output
option of the
lttng-create(1) command.
$LTTNG_HOME/.lttng
Unix user’s LTTng runtime and configuration directory.
$LTTNG_HOME/.lttng/sessions
Default directory containing the Unix user’s saved recording session configurations (see lttng-save(1) and lttng-load(1)).
/etc/lttng/sessions
Directory containing the system-wide saved recording session configurations (see lttng-save(1) and lttng-load(1)).
Note:$LTTNG_HOME
defaults to the value of the HOME
environment
variable.
Example:Read the traces of the current recording session with Babeltrace.
$
lttng view
Example:Read the traces of a specific recording session with a custom trace reader.
See the --viewer
option.
$
lttng view --viewer='/usr/bin/my-reader -zK --details=3' \ my-session
Mailing list for support and
development: lttng-dev@lists.lttng.org
IRC channel: #lttng
on irc.oftc.net
This program is part of the LTTng-tools project.
LTTng-tools is distributed under the
GNU General
Public License version 2. See the
LICENSE
file
for details.
Special thanks to Michel Dagenais and the DORSAL laboratory at École Polytechnique de Montréal for the LTTng journey.
Also thanks to the Ericsson teams working on tracing which helped us greatly with detailed bug reports and unusual test cases.