[lttv.git] / trunk / lttv / QUICKSTART.html

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<html>
<head>
  <title>Linux Trace Toolkit Quickstart</title>
</head>
  <body>

<h1>Linux Trace Toolkit Quickstart</h1>


Author : Mathieu Desnoyers, September 2005<br>
Last update : January 21st, 2009<br>

<h2>Table of Contents</h2>
<ul>

<li><a href="#intro" name="TOCintro">Introduction</a></li>
<li><a href="#section1" name="TOCsection1">Installing LTTng and LTTV from
sources</a></li>
<li><a href="#section2" name="TOCsection2">Using LTTng and LTTV</a></li>
<li><a href="#section3" name="TOCsection3">Adding kernel and user-space
tracepoints</a></li>

</ul>

<hr />

<h2><a href="#TOCintro" name="introduction">Introduction</a></h2>
<p>
This document is made of three parts : the first one explains how
to install LTTng and LTTV from sources, the second one describes the steps
to follow to trace a system and view it. The third and last part explains
briefly how to add a new trace point to the kernel and to user space
applications.

<p>
These operations are made for installing the LTTng 0.86 tracer on a linux 2.6.X
kernel. You will also find instructions for installation of LTTV 0.12.x : the
Linux Trace Toolkit Viewer. 

<p>
To see the list of compatibilities between LTTng, ltt-control, LTTV, please
refer to :
<a
href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/lttng-lttv-compatibility.html">LTTng+LTTV versions compatibility</a>

<p>
The lttng patch is necessary to have the tracing hooks in the kernel.

<br>
<br>
** Current development status **<br>
<br>
<br>
LTTng :<br>
Supported architectures : 
<li> x86 32/64 bits
<li> PowerPC 32 and 64 bits
<li> ARM (with limited timestamping precision, e.g. 1HZ. Need
architecture-specific support for better precision)
<li> MIPS
<br>
<br>
LTTV :<br>
supported architectures :<br>
<li> Intel 32/64 bits
<li> PowerPC 32 and 64 bits
<li> Possibly others. Takes care of endianness and type size difference between
the LTTng traces and the LTTV analysis tool.

<hr />

***********************************************************
** Section 1 * Installation from Debian or RPM packages  **
***********************************************************

* Create custom LTTV Debian packages

Use : dpkg-buildpackage -rfakeroot

You should then have your LTTV .deb files created for your architecture.

* Create custom LTTng packages

For building LTTng Debian packages :

Get the build tree with patches applies as explained in section 2.

make menuconfig (or xconfig or config) (customize your configuration)
make-kpkg kernel_image

You will then see your freshly created .deb in /usr/src. Install it with
dpkg -i /usr/src/(image-name).deb

Then, follow the section "Editing the system wide configuration" in section 2.


***********************************************************
** Section 2 * Installation from sources                 **
***********************************************************

* Prerequisites

Tools needed to follow the package download steps :

o wget
o bzip2
o gzip
o tar

You have to install the standard development libraries and programs necessary
to compile a kernel :

(from Documentation/Changes in the Linux kernel tree)
o  Gnu C                  2.95.3                  # gcc --version
o  Gnu make               3.79.1                  # make --version
o  binutils               2.12                    # ld -v
o  util-linux             2.10o                   # fdformat --version
o  module-init-tools      0.9.10                  # depmod -V

You might also want to have libncurses5 to have the text mode kernel
configuration menu, but there are alternatives.

Prerequisites for LTTV 0.x.x installation are :

gcc 3.2 or better
gtk 2.4 or better development libraries
  (Debian : libgtk2.0, libgtk2.0-dev)
  (Fedora : gtk2, gtk2-devel)
  note : For Fedora users : this might require at least core 3 from Fedora,
  or you might have to compile your own GTK2 library.
glib 2.4 or better development libraries
  (Debian : libglib2.0-0, libglib2.0-dev)
  (Fedora : glib2, glib2-devel)
libpopt development libraries
  (Debian : libpopt0, libpopt-dev)
  (Fedora : popt)
libpango development libraries
  (Debian : libpango1.0, libpango1.0-dev)
  (Fedora : pango, pango-devel)
libc6 development librairies 
  (Debian : libc6, libc6-dev)
  (Fedora : glibc, glibc)

* Reminder

See the list of compatibilities between LTTng, ltt-control, LTTV and
markers-userspace at :
http://ltt.polymtl.ca > LTTng+LTTV versions compatibility


* Getting the LTTng packages

su -
mkdir /usr/src/lttng
cd /usr/src/lttng
(see http://ltt.polymtl.ca/lttng for package listing)
wget http://ltt.polymtl.ca/lttng/patch-2.6.X-lttng-0.x.xx.tar.bz2
bzip2 -cd patch-2.6.X-lttng-0.x.xx.tar.bz2 | tar xvof -


* Getting LTTng kernel sources

su -
cd /usr/src
wget http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.X.tar.bz2
bzip2 -cd linux-2.6.X.tar.bz2 | tar xvof -
cd linux-2.6.X
- For LTTng 0.9.4- cat /usr/src/lttng/patch*-2.6.X-lttng-0.x.xx* | patch -p1
- For LTTng 0.9.5+ apply the patches in the order specified in the series file,
  or use quilt
cd ..
mv linux-2.6.X linux-2.6.X-lttng-0.x.xx


* Installing a LTTng kernel

su -
cd /usr/src/linux-2.6.X-lttng-0.x.xx
make menuconfig (or make xconfig or make config)
    Select the < Help > button if you are not familiar with kernel
    configuration.
    Items preceded by [*] means they has to be built into the kernel.
    Items preceded by [M] means they has to be built as modules.
    Items preceded by [ ] means they should be removed.
  go to the "General setup" section
    Select the following options :
    [*] Prompt for development and/or incomplete code/drivers
    [*] Activate markers
    [*] Activate userspace markers ABI (experimental, optional)
    [*] Immediate value optimization (optional)
    [*] Linux Trace Toolkit Next Generation (LTTng) --->
    <M> or <*> Compile lttng tracing probes
    <M> or <*> Linux Trace Toolkit High-speed Lockless Data Relay
    <M> or <*> Linux Trace Toolkit Lock-Protected Data Relay
    <M> or <*> Linux Trace Toolkit Serializer
    <M> or <*>   Linux Trace Toolkit Marker Control
    <M> or <*>     Linux Trace Toolkit Tracer
    [*] Align Linux Trace Toolkit Traces
    <M> or <*> Support logging events from userspace
    [*] Support trace extraction from crash dump
    <M> or <*> Linux Trace Toolkit Trace Controller
    <M> or <*> Linux Trace Toolkit State Dump
  Select <Exit>
  Select <Exit>
  Select <Yes>
make
make modules_install
(if necessary, create a initrd with mkinitrd or your preferate alternative)
(mkinitrd -o /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx)

-- on X86, X86_64
make install
reboot
Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.

-- on PowerPC
cp vmlinux.strip /boot/vmlinux-2.6.X-lttng-0.x.xx
cp System.map /boot/System.map-2.6.X-lttng-0.x.xx
cp .config /boot/config-2.6.X-lttng-0.x.xx
depmod -ae -F /boot/System.map-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
mkinitrd /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
(edit /etc/yaboot.conf to add a new entry pointing to your kernel : the entry
that comes first is the default kernel)
ybin
select the right entry at the yaboot prompt (see choices : tab, select : type
the kernel name followed by enter)
Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
--


* Editing the system wide configuration

You must activate debugfs and specify a mount point. This is typically done in
fstab such that it happens at boot time.

If you have never used DebugFS before, these operation would do this for you :

mkdir /mnt/debugfs
cp /etc/fstab /etc/fstab.lttng.bkp
echo "debugfs         /mnt/debugfs    debugfs rw              0       0"  >> /etc/fstab

then, rebooting or issuing the following command will activate debugfs :

mount /mnt/debugfs

You need to load the LTT modules to be able to control tracing from user
space. This is done by issuing the following commands. Note however
these commands load all LTT modules. Depending on what options you chose to
compile statically, you may not need to issue all these commands. 

modprobe ltt-trace-control
modprobe ltt-marker-control
modprobe ltt-tracer
modprobe ltt-serialize
modprobe ltt-relay
modprobe ipc-trace
modprobe kernel-trace
modprobe mm-trace
modprobe net-trace
modprobe fs-trace
modprobe jbd2-trace
modprobe ext4-trace
modprobe syscall-trace
modprobe trap-trace
#if locking tracing is wanted, uncomment the following
#modprobe lockdep-trace

If you want to have complete information about the kernel state (including all
the process names), you need to load the ltt-statedump module. This is done by
issuing the command :

modprobe ltt-statedump

You can automate at boot time loading the ltt-control module by :

cp /etc/modules /etc/modules.bkp
echo ltt-trace-control >> /etc/modules
echo ltt-marker-control >> /etc/modules
echo ltt-tracer >> /etc/modules
echo ltt-serialize >> /etc/modules
echo ltt-relay >> /etc/modules
echo ipc-trace >> /etc/modules
echo kernel-trace >> /etc/modules
echo mm-trace >> /etc/modules
echo net-trace >> /etc/modules
echo fs-trace >> /etc/modules
echo jbd2-trace >> /etc/modules
echo ext4-trace >> /etc/modules
echo syscall-trace >> /etc/modules
echo trap-trace >> /etc/modules
#if locking tracing is wanted, uncomment the following
#echo lockdep-trace >> /etc/modules


* Getting and installing the ltt-control package (on the traced machine)
(note : the ltt-control package contains lttd and lttctl. Although it has the
same name as the ltt-control kernel module, they are *not* the same thing.)
su -
cd /usr/src
wget http://ltt.polymtl.ca/lttng/ltt-control-0.x-xxxx2006.tar.gz
gzip -cd ltt-control-0.x-xxxx2008.tar.gz | tar xvof -
cd ltt-control-0.x-xxxx2006
(refer to README to see the development libraries that must be installed on you
system)
./configure
make
make install


* Userspace tracing

Make sure you selected the kernel menuconfig option :
    <M> or <*> Support logging events from userspace
And that the ltt-userspace-event kernel module is loaded if selected as a
module.

Simple userspace tracing is available through
echo "some text to record" > /mnt/debugfs/ltt/write_event

It will appear in the trace under event :
channel : userspace
event name : event


* Getting and installing the LTTV package (on the visualisation machine, same or
  different from the visualisation machine)

su -
cd /usr/src
wget http://ltt.polymtl.ca/packages/lttv-0.x.xx-xxxx2008.tar.gz
gzip -cd lttv-0.x.xx-xxxx2008.tar.gz | tar xvof -
cd lttv-0.x.xx-xxxx2008
(refer to README to see the development libraries that must be installed on your
system)
./configure
make
make install


* Getting and installing the markers-userspace package for user space tracing
(experimental)
See http://ltt.polymtl.ca/packages/markers-userspace-0.5.tar.bz2 or more recent.


***********************************************************
** Section 3 * Using LTTng and LTTV                      **
***********************************************************

* IMPORTANT : Arm Linux Kernel Markers after each boot

ltt-armall

* Use graphical LTTV to control tracing and analyse traces

lttv-gui (or /usr/local/bin/lttv-gui)
  - Spot the "Tracing Control" icon : click on it
      (it's a traffic light icon)
    - enter the root password
    - click "start"
    - click "stop"
    - Yes
      * You should now see a trace

* Use text mode LTTng to control tracing

The tracing can be controlled from a terminal by using the lttctl command (as
root).

Start tracing :

lttctl -C -w /tmp/trace1 trace1

Stop tracing and destroy trace channels :

lttctl -D trace1

see lttctl --help for details.

(note : to see if the buffers has been filled, look at the dmesg output after
lttctl -R or after stopping tracing from the GUI, it will show an event lost
count. If it is the case, try using larger buffers. See lttctl --help to learn 
how. lttv now also shows event lost messages in the console when loading a trace
with missing events or lost subbuffers.)

* Use text mode LTTV

Feel free to look in /usr/local/lib/lttv/plugins to see all the text and
graphical plugins available.

For example, a simple trace dump in text format is available with :

lttv -m textDump -t /tmp/trace

see lttv -m textDump --help for detailed command line options of textDump.

It is, in the current state of the project, very useful to use "grep" on the
text output to filter by specific event fields. You can later copy the timestamp
of the events to the clipboard and paste them in the GUI by clicking on the
bottom right label "Current time". Support for this type of filtering should
be added to the filter module soon.

* Hybrid mode

Starting from LTTng 0.5.105 and ltt-control 0.20, a new mode can be used :
hybrid. It can be especially useful when studying big workloads on a long period
of time.

When using this mode, the most important, low rate control information will be
recorded during all the trace by lttd (i.e. process creation/exit). The high
rate information (i.e. interrupt/traps/syscall entry/exit) will be kept in a
flight recorder buffer (now named flight-channelname_X).

The following lttctl commands take an hybrid trace :

Create trace channel, start lttd on normal channels, start tracing:
lttctl -C -w /tmp/trace2 -o channel.kernel.overwrite=1 trace2

Stop tracing, start lttd on flight recorder channels, destroy trace channels :
lttctl -D -w /tmp/trace2 trace2

Each "overwrite" channel is flight recorder channel.

* Flight recorder mode

The flight recorder mode writes data into overwritten buffers for all channels,
including control channels, except for the facilities tracefiles. It consists of
setting all channels to "overwrite".

The following lttctl commands take a flight recorder trace :

lttctl -C -w /tmp/trace3 -o channel.all.overwrite=1 trace3
...
lttctl -D -w /tmp/trace3 trace3


**************************************************************
** Section 4 * Adding new instrumentations with the markers **
**************************************************************

See Documentation/markers.txt and Documentation/tracepoints.txt in your kernel
tree.

* Add new events to userspace programs with userspace markers
http://ltt.polymtl.ca/packages/

Get the latest markers-userspace-*.tar.bz2 and see the Makefile and examples. It
allows inserting markers in executables and libraries, currently only on x86_32
and x86_64.

  </body>
</html>
Commit	Line	Data
c924c2c6	1	<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
	2	<html>
	3	<head>
	4	<title>Linux Trace Toolkit Quickstart</title>
	5	</head>
	6	<body>
	7
	8	<h1>Linux Trace Toolkit Quickstart</h1>
	9
	10
	11	Author : Mathieu Desnoyers, September 2005<br>
24070967	12	Last update : January 21st, 2009<br>
	13
	14	<h2>Table of Contents</h2>
	15	<ul>
	16
f9ff56f3	17	<li><a href="#intro" name="TOCintro">Introduction</a></li>
24070967	18	<li><a href="#section1" name="TOCsection1">Installing LTTng and LTTV from
	19	sources</a></li>
	20	<li><a href="#section2" name="TOCsection2">Using LTTng and LTTV</a></li>
	21	<li><a href="#section3" name="TOCsection3">Adding kernel and user-space
	22	tracepoints</a></li>
c924c2c6	23
f9ff56f3	24	</ul>
	25
	26	<hr />
	27
	28	<h2><a href="#TOCintro" name="introduction">Introduction</a></h2>
c924c2c6	29	<p>
24070967	30	This document is made of three parts : the first one explains how
	31	to install LTTng and LTTV from sources, the second one describes the steps
	32	to follow to trace a system and view it. The third and last part explains
c924c2c6	33	briefly how to add a new trace point to the kernel and to user space
	34	applications.
	35
	36	<p>
24070967	37	These operations are made for installing the LTTng 0.86 tracer on a linux 2.6.X
c924c2c6	38	kernel. You will also find instructions for installation of LTTV 0.12.x : the
	39	Linux Trace Toolkit Viewer.
	40
	41	<p>
24070967	42	To see the list of compatibilities between LTTng, ltt-control, LTTV, please
24070967	43	refer to :
c924c2c6	44	<a
	45	href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/lttng-lttv-compatibility.html">LTTng+LTTV versions compatibility</a>
	46
c924c2c6	47	<p>
24070967	48	The lttng patch is necessary to have the tracing hooks in the kernel.
c924c2c6	49
24070967	50	<br>
24070967	51	<br>
c924c2c6	52	Current development status <br>
c924c2c6	53	<br>
24070967	54	<br>
c924c2c6	55	LTTng :<br>
	56	Supported architectures :
	57	<li> x86 32/64 bits
	58	<li> PowerPC 32 and 64 bits
	59	<li> ARM (with limited timestamping precision, e.g. 1HZ. Need
	60	architecture-specific support for better precision)
	61	<li> MIPS
	62	<br>
24070967	63	<br>
c924c2c6	64	LTTV :<br>
	65	supported architectures :<br>
	66	<li> Intel 32/64 bits
	67	<li> PowerPC 32 and 64 bits
	68	<li> Possibly others. Takes care of endianness and type size difference between
	69	the LTTng traces and the LTTV analysis tool.
	70
f9ff56f3	71	<hr />
f9ff56f3	72
c924c2c6	73	***********************************************************
	74	** Section 1 * Installation from Debian or RPM packages **
	75	***********************************************************
	76
	77	* Create custom LTTV Debian packages
	78
	79	Use : dpkg-buildpackage -rfakeroot
	80
	81	You should then have your LTTV .deb files created for your architecture.
	82
	83	* Create custom LTTng packages
	84
	85	For building LTTng Debian packages :
	86
	87	Get the build tree with patches applies as explained in section 2.
	88
	89	make menuconfig (or xconfig or config) (customize your configuration)
	90	make-kpkg kernel_image
	91
	92	You will then see your freshly created .deb in /usr/src. Install it with
	93	dpkg -i /usr/src/(image-name).deb
	94
	95	Then, follow the section "Editing the system wide configuration" in section 2.
	96
	97
	98	***********************************************************
	99	** Section 2 * Installation from sources **
	100	***********************************************************
	101
	102	* Prerequisites
	103
	104	Tools needed to follow the package download steps :
	105
	106	o wget
	107	o bzip2
	108	o gzip
	109	o tar
	110
	111	You have to install the standard development libraries and programs necessary
	112	to compile a kernel :
	113
	114	(from Documentation/Changes in the Linux kernel tree)
	115	o Gnu C 2.95.3 # gcc --version
	116	o Gnu make 3.79.1 # make --version
	117	o binutils 2.12 # ld -v
	118	o util-linux 2.10o # fdformat --version
	119	o module-init-tools 0.9.10 # depmod -V
	120
	121	You might also want to have libncurses5 to have the text mode kernel
	122	configuration menu, but there are alternatives.
	123
	124	Prerequisites for LTTV 0.x.x installation are :
	125
	126	gcc 3.2 or better
	127	gtk 2.4 or better development libraries
	128	(Debian : libgtk2.0, libgtk2.0-dev)
	129	(Fedora : gtk2, gtk2-devel)
	130	note : For Fedora users : this might require at least core 3 from Fedora,
	131	or you might have to compile your own GTK2 library.
	132	glib 2.4 or better development libraries
	133	(Debian : libglib2.0-0, libglib2.0-dev)
	134	(Fedora : glib2, glib2-devel)
	135	libpopt development libraries
	136	(Debian : libpopt0, libpopt-dev)
137	(Fedora : popt)
138	libpango development libraries
139	(Debian : libpango1.0, libpango1.0-dev)
140	(Fedora : pango, pango-devel)
141	libc6 development librairies
142	(Debian : libc6, libc6-dev)
143	(Fedora : glibc, glibc)
144
145	* Reminder
146
147	See the list of compatibilities between LTTng, ltt-control, LTTV and
148	markers-userspace at :
149	http://ltt.polymtl.ca > LTTng+LTTV versions compatibility
150
151
152
153	* Getting the LTTng packages
154
155	su -
156	mkdir /usr/src/lttng
157	cd /usr/src/lttng
158	(see http://ltt.polymtl.ca/lttng for package listing)
159	wget http://ltt.polymtl.ca/lttng/patch-2.6.X-lttng-0.x.xx.tar.bz2
160	bzip2 -cd patch-2.6.X-lttng-0.x.xx.tar.bz2 \| tar xvof -
161
162
163	* Getting LTTng kernel sources
164
165	su -
166	cd /usr/src
167	wget http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.X.tar.bz2
168	bzip2 -cd linux-2.6.X.tar.bz2 \| tar xvof -
169	cd linux-2.6.X
170	- For LTTng 0.9.4- cat /usr/src/lttng/patch-2.6.X-lttng-0.x.xx \| patch -p1
171	- For LTTng 0.9.5+ apply the patches in the order specified in the series file,
172	or use quilt
173	cd ..
174	mv linux-2.6.X linux-2.6.X-lttng-0.x.xx
175
176
177	* Installing a LTTng kernel
178
179	su -
180	cd /usr/src/linux-2.6.X-lttng-0.x.xx
181	make menuconfig (or make xconfig or make config)
182	Select the < Help > button if you are not familiar with kernel
183	configuration.
184	Items preceded by [*] means they has to be built into the kernel.
185	Items preceded by [M] means they has to be built as modules.
186	Items preceded by [ ] means they should be removed.
187	go to the "General setup" section
188	Select the following options :
189	[*] Prompt for development and/or incomplete code/drivers
190	[*] Activate markers
191	[*] Activate userspace markers ABI (experimental, optional)
192	[*] Immediate value optimization (optional)
193	[*] Linux Trace Toolkit Next Generation (LTTng) --->
194	<M> or <*> Compile lttng tracing probes
195	<M> or <*> Linux Trace Toolkit High-speed Lockless Data Relay
196	<M> or <*> Linux Trace Toolkit Lock-Protected Data Relay
197	<M> or <*> Linux Trace Toolkit Serializer
198	<M> or <*> Linux Trace Toolkit Marker Control
199	<M> or <*> Linux Trace Toolkit Tracer
200	[*] Align Linux Trace Toolkit Traces
201	<M> or <*> Support logging events from userspace
202	[*] Support trace extraction from crash dump
203	<M> or <*> Linux Trace Toolkit Trace Controller
204	<M> or <*> Linux Trace Toolkit State Dump
205	Select <Exit>
206	Select <Exit>
207	Select <Yes>
208	make
209	make modules_install
210	(if necessary, create a initrd with mkinitrd or your preferate alternative)
211	(mkinitrd -o /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx)
212
213	-- on X86, X86_64
214	make install
215	reboot
216	Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
217
218	-- on PowerPC
219	cp vmlinux.strip /boot/vmlinux-2.6.X-lttng-0.x.xx
220	cp System.map /boot/System.map-2.6.X-lttng-0.x.xx
221	cp .config /boot/config-2.6.X-lttng-0.x.xx
222	depmod -ae -F /boot/System.map-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
223	mkinitrd /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
224	(edit /etc/yaboot.conf to add a new entry pointing to your kernel : the entry
225	that comes first is the default kernel)
226	ybin
227	select the right entry at the yaboot prompt (see choices : tab, select : type
228	the kernel name followed by enter)
229	Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
230	--
231
232
233
234	* Editing the system wide configuration
235
236	You must activate debugfs and specify a mount point. This is typically done in
237	fstab such that it happens at boot time.
238
239	If you have never used DebugFS before, these operation would do this for you :
240
241	mkdir /mnt/debugfs
242	cp /etc/fstab /etc/fstab.lttng.bkp
243	echo "debugfs /mnt/debugfs debugfs rw 0 0" >> /etc/fstab
244
245	then, rebooting or issuing the following command will activate debugfs :
246
247	mount /mnt/debugfs
248
249	You need to load the LTT modules to be able to control tracing from user
250	space. This is done by issuing the following commands. Note however
251	these commands load all LTT modules. Depending on what options you chose to
252	compile statically, you may not need to issue all these commands.
253
254	modprobe ltt-trace-control
255	modprobe ltt-marker-control
256	modprobe ltt-tracer
257	modprobe ltt-serialize
258	modprobe ltt-relay
259	modprobe ipc-trace
260	modprobe kernel-trace
261	modprobe mm-trace
262	modprobe net-trace
263	modprobe fs-trace
264	modprobe jbd2-trace
265	modprobe ext4-trace
266	modprobe syscall-trace
267	modprobe trap-trace
268	#if locking tracing is wanted, uncomment the following
269	#modprobe lockdep-trace
270
271	If you want to have complete information about the kernel state (including all
272	the process names), you need to load the ltt-statedump module. This is done by
273	issuing the command :
274
275	modprobe ltt-statedump
276
277	You can automate at boot time loading the ltt-control module by :
278
279	cp /etc/modules /etc/modules.bkp
280	echo ltt-trace-control >> /etc/modules
281	echo ltt-marker-control >> /etc/modules
282	echo ltt-tracer >> /etc/modules
283	echo ltt-serialize >> /etc/modules
284	echo ltt-relay >> /etc/modules
285	echo ipc-trace >> /etc/modules
286	echo kernel-trace >> /etc/modules
287	echo mm-trace >> /etc/modules
288	echo net-trace >> /etc/modules
289	echo fs-trace >> /etc/modules
290	echo jbd2-trace >> /etc/modules
291	echo ext4-trace >> /etc/modules
292	echo syscall-trace >> /etc/modules
293	echo trap-trace >> /etc/modules
294	#if locking tracing is wanted, uncomment the following
295	#echo lockdep-trace >> /etc/modules
296
297
298	* Getting and installing the ltt-control package (on the traced machine)
299	(note : the ltt-control package contains lttd and lttctl. Although it has the
300	same name as the ltt-control kernel module, they are not the same thing.)
301	su -
302	cd /usr/src
303	wget http://ltt.polymtl.ca/lttng/ltt-control-0.x-xxxx2006.tar.gz
304	gzip -cd ltt-control-0.x-xxxx2008.tar.gz \| tar xvof -
305	cd ltt-control-0.x-xxxx2006
306	(refer to README to see the development libraries that must be installed on you
307	system)
308	./configure
309	make
310	make install
311
312
313	* Userspace tracing
314
315	Make sure you selected the kernel menuconfig option :
316	<M> or <*> Support logging events from userspace
317	And that the ltt-userspace-event kernel module is loaded if selected as a
318	module.
319
320	Simple userspace tracing is available through
321	echo "some text to record" > /mnt/debugfs/ltt/write_event
322
323	It will appear in the trace under event :
324	channel : userspace
325	event name : event
326
327
328	* Getting and installing the LTTV package (on the visualisation machine, same or
329	different from the visualisation machine)
330
331	su -
332	cd /usr/src
333	wget http://ltt.polymtl.ca/packages/lttv-0.x.xx-xxxx2008.tar.gz
334	gzip -cd lttv-0.x.xx-xxxx2008.tar.gz \| tar xvof -
335	cd lttv-0.x.xx-xxxx2008
336	(refer to README to see the development libraries that must be installed on your
337	system)
338	./configure
339	make
340	make install
341
342
343	* Getting and installing the markers-userspace package for user space tracing
344	(experimental)
345	See http://ltt.polymtl.ca/packages/markers-userspace-0.5.tar.bz2 or more recent.
346
347
348
349	***********************************************************
350	** Section 3 * Using LTTng and LTTV **
351	***********************************************************
352
353	* IMPORTANT : Arm Linux Kernel Markers after each boot
354
355	ltt-armall
356
357	* Use graphical LTTV to control tracing and analyse traces
358
359	lttv-gui (or /usr/local/bin/lttv-gui)
360	- Spot the "Tracing Control" icon : click on it
361	(it's a traffic light icon)
362	- enter the root password
363	- click "start"
364	- click "stop"
365	- Yes
366	* You should now see a trace
367
368	* Use text mode LTTng to control tracing
369
370	The tracing can be controlled from a terminal by using the lttctl command (as
371	root).
372
373	Start tracing :
374
375	lttctl -C -w /tmp/trace1 trace1
376
377	Stop tracing and destroy trace channels :
378
379	lttctl -D trace1
380
381	see lttctl --help for details.
382
383	(note : to see if the buffers has been filled, look at the dmesg output after
384	lttctl -R or after stopping tracing from the GUI, it will show an event lost
385	count. If it is the case, try using larger buffers. See lttctl --help to learn
386	how. lttv now also shows event lost messages in the console when loading a trace
387	with missing events or lost subbuffers.)
388
389	* Use text mode LTTV
390
391	Feel free to look in /usr/local/lib/lttv/plugins to see all the text and
392	graphical plugins available.
393
394	For example, a simple trace dump in text format is available with :
395
396	lttv -m textDump -t /tmp/trace
397
398	see lttv -m textDump --help for detailed command line options of textDump.
399
400	It is, in the current state of the project, very useful to use "grep" on the
401	text output to filter by specific event fields. You can later copy the timestamp
402	of the events to the clipboard and paste them in the GUI by clicking on the
403	bottom right label "Current time". Support for this type of filtering should
404	be added to the filter module soon.
405
406	* Hybrid mode
407
408	Starting from LTTng 0.5.105 and ltt-control 0.20, a new mode can be used :
409	hybrid. It can be especially useful when studying big workloads on a long period
410	of time.
411
412	When using this mode, the most important, low rate control information will be
413	recorded during all the trace by lttd (i.e. process creation/exit). The high
414	rate information (i.e. interrupt/traps/syscall entry/exit) will be kept in a
415	flight recorder buffer (now named flight-channelname_X).
416
417	The following lttctl commands take an hybrid trace :
418
419	Create trace channel, start lttd on normal channels, start tracing:
420	lttctl -C -w /tmp/trace2 -o channel.kernel.overwrite=1 trace2
421
422	Stop tracing, start lttd on flight recorder channels, destroy trace channels :
423	lttctl -D -w /tmp/trace2 trace2
424
425	Each "overwrite" channel is flight recorder channel.
426
427	* Flight recorder mode
428
429	The flight recorder mode writes data into overwritten buffers for all channels,
430	including control channels, except for the facilities tracefiles. It consists of
431	setting all channels to "overwrite".
432
433	The following lttctl commands take a flight recorder trace :
434
435	lttctl -C -w /tmp/trace3 -o channel.all.overwrite=1 trace3
436	...
437	lttctl -D -w /tmp/trace3 trace3
438
439
440	**************************************************************
441	** Section 4 * Adding new instrumentations with the markers **
442	**************************************************************
443
444	See Documentation/markers.txt and Documentation/tracepoints.txt in your kernel
445	tree.
446
447	* Add new events to userspace programs with userspace markers
448	http://ltt.polymtl.ca/packages/
449
450	Get the latest markers-userspace-*.tar.bz2 and see the Makefile and examples. It
451	allows inserting markers in executables and libraries, currently only on x86_32
452	and x86_64.
453
454	</body>
455	</html>