lttng-disable-event(1): add usage examples

[lttng-tools.git] / doc / man / lttng-disable-event.1.txt

lttng-disable-event(1)
======================
:revdate: 17 May 2021


NAME
----
lttng-disable-event - Disable LTTng recording event rules


SYNOPSIS
--------
Disable one or more recording event rules matching Linux kernel
events:

[verse]
*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *disable-event* option:--kernel
      [option:--tracepoint | option:--syscall | option:--probe | option:--function]
      (option:--all-events | 'NAME'[,'NAME']...)
      [option:--session='SESSION'] [option:--channel='CHANNEL']

Disable one or more recording event rules matching user space
tracepoint or Java/Python logging events:

[verse]
*lttng* ['linkgenoptions:(GENERAL OPTIONS)'] *disable-event*
      (option:--userspace | option:--jul | option:--log4j | option:--python) [option:--tracepoint]
      (option:--all-events | 'NAME'[,'NAME']...)
      [option:--session='SESSION'] [option:--channel='CHANNEL']


DESCRIPTION
-----------
The `lttng disable-event` command disables one or more enabled recording
event rules previously created with the man:lttng-enable-event(1)
command which belong to:

With the option:--session='SESSION' option::
    The tracing session named 'SESSION'.

Without the option:--session option::
    The current tracing session (see man:lttng-concepts(7) to learn more
    about the current tracing session).

With the option:--channel='CHANNEL' option::
    The channel named 'CHANNEL'.

Without the option:--channel option::
    The channel named `channel0`.

See man:lttng-concepts(7) to learn more about recording event rules.

As of LTTng{nbsp}{lttng_version}, the `disable-event` command can only
find recording event rules to disable by their instrumentation point
type and event name conditions. Therefore, you cannot disable recording
event rules having a specific instrumentation point log level condition,
for example.

With the option:--kernel option and no instrumentation point type
condition option, the `disable-event` command disables one or more Linux
kernel recording event rules regardless of their instrumentation point
type.

List the recording event rules of a given tracing session
and/or channel with the man:lttng-list(1) command.

Without the option:--all-events option, the `disable-event` command
disables one recording event rule per 'NAME' argument. 'NAME' is the
exact event name condition pattern of the recording event rule to
disable, as listed in the output of `lttng list` (see
man:lttng-list(1)).

You may disable an enabled recording event rule regardless of the
activity (started or stopped) of its tracing session (see
man:lttng-start(1) and man:lttng-stop(1)).

See the <<examples,EXAMPLES>> section below for usage examples.


include::common-lttng-cmd-options-head.txt[]


Tracing domain
~~~~~~~~~~~~~~
One of:

option:-j, option:--jul::
    Disable recording event rules in the `java.util.logging` (JUL)
    domain.

option:-k, option:--kernel::
    Disable recording event rules in the Linux kernel domain.

option:-l, option:--log4j::
    Disable recording event rules in the Apache log4j domain.

option:-p, option:--python::
    Disable recording event rules in the Python domain.

option:-u, option:--userspace::
    Disable recording event rules in the user space tracing domain.


Recording target
~~~~~~~~~~~~~~~~
option:-c 'CHANNEL', option:--channel='CHANNEL'::
    Disable recording event rules attached to the channel named
    'CHANNEL' instead of `channel0`.

option:-s 'SESSION', option:--session='SESSION'::
    Disable recording event rules in the tracing session named 'SESSION'
    instead of the current tracing session.


Instrumentation point type condition
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
At most one of:

option:--function::
    Only disable recording event rules which match Linux kretprobe
    events.
+
Only available with the option:--kernel option.

option:--probe::
    Only disable recording event rules which match Linux kprobe events.
+
Only available with the option:--kernel option.

option:--syscall::
    Only disable recording event rules which match Linux system call
    events.
+
Only available with the option:--kernel option.

option:--tracepoint::
    Only disable recording event rules which match:
+
--
With the option:--kernel or option:--userspace option:::
    LTTng tracepoint events.
With the option:--jul, option:--log4j, or option:--python option:::
    Logging events.
--


Event name condition
~~~~~~~~~~~~~~~~~~~~
option:-a, option:--all-events::
    Disable recording event rules regardless of their event name
    condition.


include::common-lttng-cmd-help-options.txt[]


include::common-lttng-cmd-after-options.txt[]


[[examples]]
EXAMPLES
--------
.Disable all Linux kernel tracepoint recording event rules in the default channel of the current tracing session.
====
See the option:--all-events option.

[role="term"]
----
$ lttng disable-event --kernel --tracepoint --all-events
----
====

.Disable specific Apache log4j recording event rules in the default channel of a specific tracing session.
====
See the option:--session option.

[role="term"]
----
$ lttng disable-event --session=my-session --log4j \
                      MySingleton,MyProxy,MyFacade
----
====

.Disable all user space recording event rules in a specific channel of the current tracing session.
====
See the option:--channel option.

[role="term"]
----
$ lttng disable-event --channel=my-channel --userspace \
                      --all-events
----
====

.Disable specific Linux kernel system call recording event rules in the default channel of the current tracing session.
====
[role="term"]
----
$ lttng disable-event --kernel --syscall pipe2,eventfd
----
====


include::common-footer.txt[]


SEE ALSO
--------
man:lttng(1),
man:lttng-enable-event(1),
man:lttng-list(1),
man:lttng-concepts(7)