X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=doc%2Fquickstart.txt;h=7078eecc97fb581621b58a250a448ac1f2724c59;hb=4771f025b27e92983c1c0816c4cf5760d229c287;hp=0cf44d69b0e45d6ae27cc516b85e17cd652574ce;hpb=617d7d159c22a17dd0191597945eb00303935e96;p=lttng-tools.git diff --git a/doc/quickstart.txt b/doc/quickstart.txt index 0cf44d69b..7078eecc9 100644 --- a/doc/quickstart.txt +++ b/doc/quickstart.txt @@ -18,7 +18,7 @@ installed. See http://lttng.org/lttng2.0 for more instructions for that part. For user-space tracing, you'll need an instrumented application, please see http://lttng.org/ust. -lttng-tools provide a session daemon (ltt-sessiond) that acts as a tracing +lttng-tools provide a session daemon (lttng-sessiond) that acts as a tracing registry. To trace any instrumented applications or the kernel, a registered tracing session is needed beforehand. To interact with the session daemon and a tracing session, you should use the lttng command line UI (lttng). @@ -36,13 +36,13 @@ The next sections explain how to do tracing :) Kernel Tracing -------------- -You have to modprobe the lttng-modules manually or the session daemon will do -it for you if those modules can be found on your system. +You can start the session daemon by invoking the command "lttng-sessiond", +or let the lttng command line tool do it for you. The session daemon +loads the LTTng tracer modules for you if those modules can be found on +your system. If they are not found, the kernel tracing feature will be +unavailable. -Again, you can then start the session daemon (ltt-sessiond) by hand or the -lttng command line tool will do it for you. - -List possible kernel events: +List available kernel events: # lttng list -k @@ -55,35 +55,43 @@ If you have multiple sessions, you can change the current session by using # lttng set-session myothersession -2) Enable event(s). Here for example, we want only 'sched_switch' and -'sys_enter' events for the kernel (-k/--kernel). +2) Enable all tracepoints and all system call events. + +# lttng enable-event -a -k -# lttng enable-event sched_switch,sys_enter -k +3) Enable tracepoint event(s). Here for example, we want only +'sched_switch' and 'sched_wakeup' events for the kernel (-k/--kernel). -or enable ALL events (-a/--all): +# lttng enable-event sched_switch,sched_wakeup -k -# lttng enable-event -a -k +or enable ALL tracepoint events: + +# lttng enable-event -a -k --tracepoint + +4) Enable all system call event(s). + +# lttng enable-event -a -k --syscall -3) Enable kprobes and/or the function tracer with lttng +5) Enable kprobes and/or the function tracer with lttng This is a new feature made possible by the new LTTng 2.0 kernel tracer. You can enable a dynamic probe and data will be output in the trace along side with your tracing data. -# lttng enable-event aname --probe symbol+0xffff7260695 +# lttng enable-event aname -k --probe symbol+0x0 or -# lttng enable-event aname --probe 0xffff7260695 +# lttng enable-event aname -k --probe 0xffff7260695 Either an
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