2 id: tracing-the-linux-kernel
5 Make sure LTTng-tools and LTTng-modules packages
6 [are installed](#doc-installing-lttng).
8 Since you're about to trace the Linux kernel itself, let's look at the
9 available kernel events using the `lttng` tool, which has a
10 Git-like command line structure:
16 Before tracing, you need to create a session:
19 sudo lttng create my-session
24 <span class="t">Tip:</span>You can avoid using <code>sudo</code> in
25 the previous and following commands if your user is a member of the
26 <a href="/docs/#doc-lttng-sessiond" class="int"><code>tracing</code>
31 `my-session` is the tracing session name and could be anything you
32 like. `auto` is used if omitted.
34 Let's now enable some events for this session:
37 sudo lttng enable-event --kernel sched_switch,sched_process_fork
40 or you might want to simply enable all available kernel events (beware
41 that trace files grow rapidly when doing this):
44 sudo lttng enable-event --kernel --all
53 By default, traces are saved in
54 <code>~/lttng-traces/<em>name</em>-<em>date</em>-<em>time</em></code>,
55 where <code><em>name</em></code> is the session name.
57 When you're done tracing:
64 Although `destroy` looks scary here, it doesn't actually destroy the
65 outputted trace files: it only destroys the tracing session.
67 What's next? Have a look at
68 [Viewing and analyzing your traces](#doc-viewing-and-analyzing-your-traces)
69 to view and analyze the trace you just recorded.