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

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  <title>Linux Trace Toolkit Next Generation User Documentation</title>
</head>
  <body>

<h1>Linux Trace Toolkit Next Generation User Documentation</h1>

Author : Mathieu Desnoyers, September 2005<br>
Last update : January 21st, 2009<br>
(originally known as the LTTng QUICKSTART guide)

<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>
<ul>
<li><a href="#prerequisites" name="TOCprerequisites">Prerequisistes</li>
<li><a href="#getlttng" name="TOCgetlttng">Getting the LTTng packages</li>
<li><a href="#getlttngsrc" name="TOCgetlttngsrc">Getting the LTTng kernel sources</li>
<li><a href="#installlttng" name="TOCinstalllttng">Installing a LTTng kernel</li>
<li><a href="#editconfig" name="TOCeditconfig">Editing the system wide
configuration</a>
<li><a href="#getlttctl" name="TOCgetlttctl">Getting and installing the
ltt-control package</li>
<li><a href="#userspacetracing" name="TOCuserspacetracing">Userspace Tracing</li>
<li><a href="#getlttv" name="TOCgetlttv">Getting and installing the LTTV package</ul>
<li><a href="#section2" name="TOCsection2">Using LTTng and LTTV</a></li>
<li><a href="#section3" name="TOCsection3">Adding kernel and user-space
instrumentation</a>
<ul>
<li><a href="#kerneltp" name="TOCkerneltp">Adding kernel instrumentation</a></li>
<li><a href="#usertp" name="TOCusertp">Adding userspace instrumentation</a></li>
</ul>

<li><a href="#section4" name="TOCsection4">Creating Debian and RPM packages
from LTTV</a>

</ul>

<hr />

<h2><a href="#TOCintro" name="intro">Introduction</a></h2>
<p>
This document is made of four 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 part explains
briefly how to add a new trace point to the kernel and to user space
applications. The fourth and last part explains how to create Debian or RPM
packages from the LTTng and LTTV sources.
<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. 
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>
The lttng patch is necessary to have the tracing hooks in the kernel.

<br>
<br>
Supported architectures : 
br>
LTTng :<br>
<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>
<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 />


<h2><a href="#TOCsection1" name="section1">Installation from sources</a></h2>
<p>

<h3><a href="#TOCprerequisites" name="prerequisites">Prerequisites</a></h3>
<ul>
<p>
Tools needed to follow the package download steps :

<li>wget
<li>bzip2
<li>gzip
<li>tar

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

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

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

<p>
Prerequisites for LTTV 0.x.x installation are :

<PRE>
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)
</PRE>
</ul>

<li>Reminder</li>

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


<h3><a href="#TOCgetlttng" name="getlttng">Getting the LTTng packages</a></h3>

<PRE>
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 -
</PRE>


<h3><a href="#TOCgetlttngsrc" name="getlttngsrc">Getting LTTng kernel sources</a></h3>

<PRE>
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
</PRE>


<h3><a href="#TOCinstalllttng" name="installlttng">Installing a LTTng kernel</a></h3>

<PRE>
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.
--
</PRE>

<h3><a href="#TOCeditconfig" name="editconfig">Editing the system wide
configuration</a></h3>

<p>
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 :

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

<p>
then, rebooting or issuing the following command will activate debugfs :
<PRE>
mount /mnt/debugfs
</PRE>

<p>
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. 

<PRE>
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
</PRE>

<p>
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 :

<PRE>
modprobe ltt-statedump
</PRE>
<p>
You can automate at boot time loading the ltt-control module by :

<PRE>
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
</PRE>


<h3><a href="#TOCgetlttctl" name="getlttctl">Getting and installing the
ltt-control package (on the traced machine)</a></h3>
<p>
(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.)

<PRE>
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
</PRE>

<h3><a href="#TOCuserspacetracing" name="userspacetracing">Userspace tracing</a></h3>

<PRE>
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
</PRE>

<h3><a href="#TOCgetlttv" name="getlttv">Getting and installing the LTTV package
(on the visualisation machine, same
or different from the visualisation machine)</a></h3>

<PRE>
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
</PRE>

<hr />


<h2><a href="#TOCsection2" name="section2">Using LTTng and LTTV</a></h2>

<li>IMPORTANT : Arm Linux Kernel Markers after each boot</li>
<PRE>
ltt-armall
</PRE>

<li>Use graphical LTTV to control tracing and analyse traces</li>
<PRE>
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
</PRE>

<li>Use text mode LTTng to control tracing</li>
<PRE>
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.
</PRE>
<p>
(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.)

<li>Use text mode LTTV</li>
<p>
Feel free to look in /usr/local/lib/lttv/plugins to see all the text and
graphical plugins available.
<p>
For example, a simple trace dump in text format is available with :
<PRE>
lttv -m textDump -t /tmp/trace
</PRE>
<p>
See lttv -m textDump --help for detailed command line options of textDump.
<p>
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.

<li>Hybrid mode</li>
<p>
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.
<p>
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).
<p>
The following lttctl commands take an hybrid trace :
<p>
Create trace channel, start lttd on normal channels, start tracing:
<PRE>
lttctl -C -w /tmp/trace2 -o channel.kernel.overwrite=1 trace2
</PRE>
<p>
Stop tracing, start lttd on flight recorder channels, destroy trace channels :
<PRE>
lttctl -D -w /tmp/trace2 trace2
</PRE>
<p>
Each "overwrite" channel is flight recorder channel.

<li>Flight recorder mode</li>
<p>
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".
<p>
The following lttctl commands take a flight recorder trace :
<PRE>
lttctl -C -w /tmp/trace3 -o channel.all.overwrite=1 trace3
...
lttctl -D -w /tmp/trace3 trace3
</PRE>

<hr />


<h2><a href="#TOCsection3" name="section3">Adding new instrumentations with the
markers</a></h2>
<p>

<h3><a href="#TOCkerneltp" name="kerneltp">Adding kernel
instrumentation</a></h3>

<p>
See <a
href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=blob;f=Documentation/markers.txt">Documentation/markers.txt</a>
and <a
href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=blob;f=Documentation/tracepoints.txt">Documentation/tracepoints.txt</a> in your kernel
tree.
<p>
Also see <a
href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=tree;f=ltt/probes">ltt/probes/</a>
for LTTng probe examples.

<h3><a href="#TOCusertp" name="usertp">Adding userspace instrumentation</a></h3>

<li>Add new events to userspace programs with
<a href="http://ltt.polymtl.ca/packages/">userspace markers packages</a></li>

<p>
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.
See <a
href="http://ltt.polymtl.ca/packages/markers-userspace-0.5.tar.bz2">markers-userspace-0.5.tar.bz2</a> or more recent.

<p>
Note that a new design document for a 3rd generation of tracepoint/marker-based
userspace tracing is available at <a
href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/ust.html">LTTng User-space Tracing
Design"</a>. This new infrastructure is not yet implemented.

<p>
The easy quick-and-dirty way to perform userspace tracing is currently to write
an string to /mnt/debugfs/ltt/write_event. See <a
href="#userspacetracing">Userspace tracing</a> in the
installation for sources section of this document.

<hr />

<h2><a href="#TOCsection4" name="section4">Creating Debian or RPM packages</a></h2>
<p>

<li>Create custom LTTV Debian packages</li>

<PRE>
Use : dpkg-buildpackage -rfakeroot
</PRE>
<p>
You should then have your LTTV .deb files created for your architecture.

<li>Create custom LTTng packages</li>
<p>
For building LTTng Debian packages :
get the build tree with patches applies as explained in section 2.

<PRE>
make menuconfig (or xconfig or config) (customize your configuration)
make-kpkg kernel_image
</PRE>
<p>
You will then see your freshly created .deb in /usr/src. Install it with
<PRE>
dpkg -i /usr/src/(image-name).deb
</PRE>
<p>
Then, follow the section "Editing the system wide configuration" in section 2.


  </body>
</html>
Commit	Line	Data
	1	<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
	2	<html>
	3	<head>
	4	<title>Linux Trace Toolkit Next Generation User Documentation</title>
	5	</head>
	6	<body>
	7
	8	<h1>Linux Trace Toolkit Next Generation User Documentation</h1>
	9
	10	Author : Mathieu Desnoyers, September 2005<br>
	11	Last update : January 21st, 2009<br>
	12	(originally known as the LTTng QUICKSTART guide)
	13
	14	<h2>Table of Contents</h2>
	15	<ul>
	16
	17	<li><a href="#intro" name="TOCintro">Introduction</a></li>
	18	<li><a href="#section1" name="TOCsection1">Installing LTTng and LTTV from
	19	sources</a></li>
	20	<ul>
	21	<li><a href="#prerequisites" name="TOCprerequisites">Prerequisistes</li>
	22	<li><a href="#getlttng" name="TOCgetlttng">Getting the LTTng packages</li>
	23	<li><a href="#getlttngsrc" name="TOCgetlttngsrc">Getting the LTTng kernel sources</li>
	24	<li><a href="#installlttng" name="TOCinstalllttng">Installing a LTTng kernel</li>
	25	<li><a href="#editconfig" name="TOCeditconfig">Editing the system wide
	26	configuration</a>
	27	<li><a href="#getlttctl" name="TOCgetlttctl">Getting and installing the
	28	ltt-control package</li>
	29	<li><a href="#userspacetracing" name="TOCuserspacetracing">Userspace Tracing</li>
	30	<li><a href="#getlttv" name="TOCgetlttv">Getting and installing the LTTV package</ul>
	31	<li><a href="#section2" name="TOCsection2">Using LTTng and LTTV</a></li>
	32	<li><a href="#section3" name="TOCsection3">Adding kernel and user-space
	33	instrumentation</a>
	34	<ul>
	35	<li><a href="#kerneltp" name="TOCkerneltp">Adding kernel instrumentation</a></li>
	36	<li><a href="#usertp" name="TOCusertp">Adding userspace instrumentation</a></li>
	37	</ul>
	38
	39	<li><a href="#section4" name="TOCsection4">Creating Debian and RPM packages
	40	from LTTV</a>
	41
	42	</ul>
	43
	44	<hr />
	45
	46	<h2><a href="#TOCintro" name="intro">Introduction</a></h2>
	47	<p>
	48	This document is made of four parts : the first one explains how
	49	to install LTTng and LTTV from sources, the second one describes the steps
	50	to follow to trace a system and view it. The third part explains
	51	briefly how to add a new trace point to the kernel and to user space
	52	applications. The fourth and last part explains how to create Debian or RPM
	53	packages from the LTTng and LTTV sources.
	54	<p>
	55	These operations are made for installing the LTTng 0.86 tracer on a linux 2.6.X
	56	kernel. You will also find instructions for installation of LTTV 0.12.x : the
	57	Linux Trace Toolkit Viewer.
	58	To see the list of compatibilities between LTTng, ltt-control, LTTV, please
	59	refer to :
	60	<a
	61	href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/lttng-lttv-compatibility.html">LTTng+LTTV versions compatibility</a>
	62	The lttng patch is necessary to have the tracing hooks in the kernel.
	63
	64	<br>
	65	<br>
	66	Supported architectures :
	67	br>
	68	LTTng :<br>
	69	<li> x86 32/64 bits
	70	<li> PowerPC 32 and 64 bits
	71	<li> ARM (with limited timestamping precision, e.g. 1HZ. Need
	72	architecture-specific support for better precision)
	73	<li> MIPS
	74	<br>
	75	<br>
	76	LTTV :<br>
	77	<li> Intel 32/64 bits
	78	<li> PowerPC 32 and 64 bits
	79	<li> Possibly others. Takes care of endianness and type size difference between
	80	the LTTng traces and the LTTV analysis tool.
	81
	82	<hr />
	83
	84
	85	<h2><a href="#TOCsection1" name="section1">Installation from sources</a></h2>
	86	<p>
	87
	88	<h3><a href="#TOCprerequisites" name="prerequisites">Prerequisites</a></h3>
	89	<ul>
	90	<p>
	91	Tools needed to follow the package download steps :
	92
	93	<li>wget
	94	<li>bzip2
	95	<li>gzip
	96	<li>tar
	97
	98	<p>
	99	You have to install the standard development libraries and programs necessary
	100	to compile a kernel :
	101
	102	<PRE>
	103	(from Documentation/Changes in the Linux kernel tree)
	104	Gnu C 2.95.3 # gcc --version
	105	Gnu make 3.79.1 # make --version
	106	binutils 2.12 # ld -v
	107	util-linux 2.10o # fdformat --version
	108	module-init-tools 0.9.10 # depmod -V
	109	</PRE>
	110
	111	<p>
	112	You might also want to have libncurses5 to have the text mode kernel
	113	configuration menu, but there are alternatives.
	114
	115	<p>
	116	Prerequisites for LTTV 0.x.x installation are :
	117
	118	<PRE>
	119	gcc 3.2 or better
	120	gtk 2.4 or better development libraries
	121	(Debian : libgtk2.0, libgtk2.0-dev)
	122	(Fedora : gtk2, gtk2-devel)
	123	note : For Fedora users : this might require at least core 3 from Fedora,
	124	or you might have to compile your own GTK2 library.
	125	glib 2.4 or better development libraries
	126	(Debian : libglib2.0-0, libglib2.0-dev)
	127	(Fedora : glib2, glib2-devel)
	128	libpopt development libraries
	129	(Debian : libpopt0, libpopt-dev)
	130	(Fedora : popt)
	131	libpango development libraries
	132	(Debian : libpango1.0, libpango1.0-dev)
	133	(Fedora : pango, pango-devel)
	134	libc6 development librairies
	135	(Debian : libc6, libc6-dev)
	136	(Fedora : glibc, glibc)
	137	</PRE>
	138	</ul>
	139
	140	<li>Reminder</li>
	141
	142	<p>
	143	See the list of compatibilities between LTTng, ltt-control and LTTV at :
	144	<a
	145	href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/lttng-lttv-compatibility.html">LTTng+LTTV
	146	versions compatibility</a>.
	147
	148
	149	<h3><a href="#TOCgetlttng" name="getlttng">Getting the LTTng packages</a></h3>
	150
	151	<PRE>
	152	su -
	153	mkdir /usr/src/lttng
	154	cd /usr/src/lttng
	155	(see http://ltt.polymtl.ca/lttng for package listing)
	156	wget http://ltt.polymtl.ca/lttng/patch-2.6.X-lttng-0.x.xx.tar.bz2
	157	bzip2 -cd patch-2.6.X-lttng-0.x.xx.tar.bz2 \| tar xvof -
	158	</PRE>
	159
	160
	161	<h3><a href="#TOCgetlttngsrc" name="getlttngsrc">Getting LTTng kernel sources</a></h3>
	162
	163	<PRE>
	164	su -
	165	cd /usr/src
	166	wget http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.X.tar.bz2
	167	bzip2 -cd linux-2.6.X.tar.bz2 \| tar xvof -
	168	cd linux-2.6.X
	169	- For LTTng 0.9.4- cat /usr/src/lttng/patch-2.6.X-lttng-0.x.xx \| patch -p1
	170	- For LTTng 0.9.5+ apply the patches in the order specified in the series file,
	171	or use quilt
	172	cd ..
	173	mv linux-2.6.X linux-2.6.X-lttng-0.x.xx
	174	</PRE>
	175
	176
	177	<h3><a href="#TOCinstalllttng" name="installlttng">Installing a LTTng kernel</a></h3>
	178
	179	<PRE>
	180	su -
	181	cd /usr/src/linux-2.6.X-lttng-0.x.xx
	182	make menuconfig (or make xconfig or make config)
	183	Select the < Help > button if you are not familiar with kernel
	184	configuration.
	185	Items preceded by [*] means they has to be built into the kernel.
	186	Items preceded by [M] means they has to be built as modules.
	187	Items preceded by [ ] means they should be removed.
	188	go to the "General setup" section
	189	Select the following options :
	190	[*] Prompt for development and/or incomplete code/drivers
	191	[*] Activate markers
	192	[*] Activate userspace markers ABI (experimental, optional)
	193	[*] Immediate value optimization (optional)
	194	[*] Linux Trace Toolkit Next Generation (LTTng) --->
	195	<M> or <*> Compile lttng tracing probes
	196	<M> or <*> Linux Trace Toolkit High-speed Lockless Data Relay
	197	<M> or <*> Linux Trace Toolkit Lock-Protected Data Relay
	198	<M> or <*> Linux Trace Toolkit Serializer
	199	<M> or <*> Linux Trace Toolkit Marker Control
	200	<M> or <*> Linux Trace Toolkit Tracer
	201	[*] Align Linux Trace Toolkit Traces
	202	<M> or <*> Support logging events from userspace
	203	[*] Support trace extraction from crash dump
	204	<M> or <*> Linux Trace Toolkit Trace Controller
	205	<M> or <*> Linux Trace Toolkit State Dump
	206	Select <Exit>
	207	Select <Exit>
	208	Select <Yes>
	209	make
	210	make modules_install
	211	(if necessary, create a initrd with mkinitrd or your preferate alternative)
	212	(mkinitrd -o /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx)
	213
	214	-- on X86, X86_64
	215	make install
	216	reboot
	217	Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
	218
	219	-- on PowerPC
	220	cp vmlinux.strip /boot/vmlinux-2.6.X-lttng-0.x.xx
	221	cp System.map /boot/System.map-2.6.X-lttng-0.x.xx
	222	cp .config /boot/config-2.6.X-lttng-0.x.xx
	223	depmod -ae -F /boot/System.map-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
	224	mkinitrd /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
	225	(edit /etc/yaboot.conf to add a new entry pointing to your kernel : the entry
	226	that comes first is the default kernel)
	227	ybin
	228	select the right entry at the yaboot prompt (see choices : tab, select : type
	229	the kernel name followed by enter)
	230	Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
	231	--
	232	</PRE>
	233
	234	<h3><a href="#TOCeditconfig" name="editconfig">Editing the system wide
	235	configuration</a></h3>
	236
	237	<p>
	238	You must activate debugfs and specify a mount point. This is typically done in
	239	fstab such that it happens at boot time. If you have never used DebugFS before,
	240	these operation would do this for you :
	241
	242	<PRE>
	243	mkdir /mnt/debugfs
	244	cp /etc/fstab /etc/fstab.lttng.bkp
	245	echo "debugfs /mnt/debugfs debugfs rw 0 0" >> /etc/fstab
	246	</PRE>
	247
	248	<p>
	249	then, rebooting or issuing the following command will activate debugfs :
	250	<PRE>
	251	mount /mnt/debugfs
	252	</PRE>
	253
	254	<p>
	255	You need to load the LTT modules to be able to control tracing from user
	256	space. This is done by issuing the following commands. Note however
	257	these commands load all LTT modules. Depending on what options you chose to
	258	compile statically, you may not need to issue all these commands.
	259
	260	<PRE>
	261	modprobe ltt-trace-control
	262	modprobe ltt-marker-control
	263	modprobe ltt-tracer
	264	modprobe ltt-serialize
	265	modprobe ltt-relay
	266	modprobe ipc-trace
	267	modprobe kernel-trace
	268	modprobe mm-trace
	269	modprobe net-trace
	270	modprobe fs-trace
	271	modprobe jbd2-trace
	272	modprobe ext4-trace
	273	modprobe syscall-trace
	274	modprobe trap-trace
	275	#if locking tracing is wanted, uncomment the following
	276	#modprobe lockdep-trace
	277	</PRE>
	278
	279	<p>
	280	If you want to have complete information about the kernel state (including all
	281	the process names), you need to load the ltt-statedump module. This is done by
	282	issuing the command :
	283
	284	<PRE>
	285	modprobe ltt-statedump
	286	</PRE>
	287	<p>
	288	You can automate at boot time loading the ltt-control module by :
	289
	290	<PRE>
	291	cp /etc/modules /etc/modules.bkp
	292	echo ltt-trace-control >> /etc/modules
	293	echo ltt-marker-control >> /etc/modules
	294	echo ltt-tracer >> /etc/modules
	295	echo ltt-serialize >> /etc/modules
	296	echo ltt-relay >> /etc/modules
	297	echo ipc-trace >> /etc/modules
	298	echo kernel-trace >> /etc/modules
	299	echo mm-trace >> /etc/modules
	300	echo net-trace >> /etc/modules
	301	echo fs-trace >> /etc/modules
	302	echo jbd2-trace >> /etc/modules
	303	echo ext4-trace >> /etc/modules
	304	echo syscall-trace >> /etc/modules
	305	echo trap-trace >> /etc/modules
	306	#if locking tracing is wanted, uncomment the following
	307	#echo lockdep-trace >> /etc/modules
	308	</PRE>
	309
	310
	311	<h3><a href="#TOCgetlttctl" name="getlttctl">Getting and installing the
	312	ltt-control package (on the traced machine)</a></h3>
	313	<p>
	314	(note : the ltt-control package contains lttd and lttctl. Although it has the
	315	same name as the ltt-control kernel module, they are not the same thing.)
	316
	317	<PRE>
	318	su -
	319	cd /usr/src
	320	wget http://ltt.polymtl.ca/lttng/ltt-control-0.x-xxxx2006.tar.gz
	321	gzip -cd ltt-control-0.x-xxxx2008.tar.gz \| tar xvof -
	322	cd ltt-control-0.x-xxxx2006
	323	(refer to README to see the development libraries that must be installed on you
	324	system)
	325	./configure
	326	make
	327	make install
	328	</PRE>
	329
	330	<h3><a href="#TOCuserspacetracing" name="userspacetracing">Userspace tracing</a></h3>
	331
	332	<PRE>
	333	Make sure you selected the kernel menuconfig option :
	334	<M> or <*> Support logging events from userspace
	335	And that the ltt-userspace-event kernel module is loaded if selected as a
	336	module.
	337
	338	Simple userspace tracing is available through
	339	echo "some text to record" > /mnt/debugfs/ltt/write_event
	340
	341	It will appear in the trace under event :
	342	channel : userspace
	343	event name : event
	344	</PRE>
	345
	346	<h3><a href="#TOCgetlttv" name="getlttv">Getting and installing the LTTV package
	347	(on the visualisation machine, same
	348	or different from the visualisation machine)</a></h3>
	349
	350	<PRE>
	351	su -
	352	cd /usr/src
	353	wget http://ltt.polymtl.ca/packages/lttv-0.x.xx-xxxx2008.tar.gz
	354	gzip -cd lttv-0.x.xx-xxxx2008.tar.gz \| tar xvof -
	355	cd lttv-0.x.xx-xxxx2008
	356	(refer to README to see the development libraries that must be installed on your
	357	system)
	358	./configure
	359	make
	360	make install
	361	</PRE>
	362
	363	<hr />
	364
	365
	366	<h2><a href="#TOCsection2" name="section2">Using LTTng and LTTV</a></h2>
	367
	368	<li>IMPORTANT : Arm Linux Kernel Markers after each boot</li>
	369	<PRE>
	370	ltt-armall
	371	</PRE>
	372
	373	<li>Use graphical LTTV to control tracing and analyse traces</li>
	374	<PRE>
	375	lttv-gui (or /usr/local/bin/lttv-gui)
	376	- Spot the "Tracing Control" icon : click on it
	377	(it's a traffic light icon)
	378	- enter the root password
	379	- click "start"
	380	- click "stop"
	381	- Yes
	382	* You should now see a trace
	383	</PRE>
	384
	385	<li>Use text mode LTTng to control tracing</li>
	386	<PRE>
	387	The tracing can be controlled from a terminal by using the lttctl command (as
	388	root).
	389
	390	Start tracing :
	391
	392	lttctl -C -w /tmp/trace1 trace1
	393
	394	Stop tracing and destroy trace channels :
	395
	396	lttctl -D trace1
	397
	398	see lttctl --help for details.
	399	</PRE>
	400	<p>
	401	(note : to see if the buffers has been filled, look at the dmesg output after
	402	lttctl -R or after stopping tracing from the GUI, it will show an event lost
	403	count. If it is the case, try using larger buffers. See lttctl --help to learn
	404	how. lttv now also shows event lost messages in the console when loading a trace
	405	with missing events or lost subbuffers.)
	406
	407	<li>Use text mode LTTV</li>
	408	<p>
	409	Feel free to look in /usr/local/lib/lttv/plugins to see all the text and
	410	graphical plugins available.
	411	<p>
	412	For example, a simple trace dump in text format is available with :
	413	<PRE>
	414	lttv -m textDump -t /tmp/trace
	415	</PRE>
	416	<p>
	417	See lttv -m textDump --help for detailed command line options of textDump.
	418	<p>
	419	It is, in the current state of the project, very useful to use "grep" on the
	420	text output to filter by specific event fields. You can later copy the timestamp
	421	of the events to the clipboard and paste them in the GUI by clicking on the
	422	bottom right label "Current time". Support for this type of filtering should
	423	be added to the filter module soon.
	424
	425	<li>Hybrid mode</li>
	426	<p>
	427	Starting from LTTng 0.5.105 and ltt-control 0.20, a new mode can be used :
	428	hybrid. It can be especially useful when studying big workloads on a long period
	429	of time.
	430	<p>
	431	When using this mode, the most important, low rate control information will be
	432	recorded during all the trace by lttd (i.e. process creation/exit). The high
	433	rate information (i.e. interrupt/traps/syscall entry/exit) will be kept in a
	434	flight recorder buffer (now named flight-channelname_X).
	435	<p>
	436	The following lttctl commands take an hybrid trace :
	437	<p>
	438	Create trace channel, start lttd on normal channels, start tracing:
	439	<PRE>
	440	lttctl -C -w /tmp/trace2 -o channel.kernel.overwrite=1 trace2
	441	</PRE>
	442	<p>
	443	Stop tracing, start lttd on flight recorder channels, destroy trace channels :
	444	<PRE>
	445	lttctl -D -w /tmp/trace2 trace2
	446	</PRE>
	447	<p>
	448	Each "overwrite" channel is flight recorder channel.
	449
	450	<li>Flight recorder mode</li>
	451	<p>
	452	The flight recorder mode writes data into overwritten buffers for all channels,
	453	including control channels, except for the facilities tracefiles. It consists of
	454	setting all channels to "overwrite".
	455	<p>
	456	The following lttctl commands take a flight recorder trace :
	457	<PRE>
	458	lttctl -C -w /tmp/trace3 -o channel.all.overwrite=1 trace3
	459	...
	460	lttctl -D -w /tmp/trace3 trace3
	461	</PRE>
	462
	463	<hr />
	464
	465
	466	<h2><a href="#TOCsection3" name="section3">Adding new instrumentations with the
	467	markers</a></h2>
	468	<p>
	469
	470	<h3><a href="#TOCkerneltp" name="kerneltp">Adding kernel
	471	instrumentation</a></h3>
	472
	473	<p>
	474	See <a
	475	href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=blob;f=Documentation/markers.txt">Documentation/markers.txt</a>
	476	and <a
	477	href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=blob;f=Documentation/tracepoints.txt">Documentation/tracepoints.txt</a> in your kernel
	478	tree.
	479	<p>
	480	Also see <a
	481	href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=tree;f=ltt/probes">ltt/probes/</a>
	482	for LTTng probe examples.
	483
	484	<h3><a href="#TOCusertp" name="usertp">Adding userspace instrumentation</a></h3>
	485
	486	<li>Add new events to userspace programs with
	487	<a href="http://ltt.polymtl.ca/packages/">userspace markers packages</a></li>
	488
	489	<p>
	490	Get the latest markers-userspace-*.tar.bz2 and see the Makefile and examples. It
	491	allows inserting markers in executables and libraries, currently only on x86_32
	492	and x86_64.
	493	See <a
	494	href="http://ltt.polymtl.ca/packages/markers-userspace-0.5.tar.bz2">markers-userspace-0.5.tar.bz2</a> or more recent.
	495
	496	<p>
	497	Note that a new design document for a 3rd generation of tracepoint/marker-based
	498	userspace tracing is available at <a
	499	href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/ust.html">LTTng User-space Tracing
	500	Design"</a>. This new infrastructure is not yet implemented.
	501
	502	<p>
	503	The easy quick-and-dirty way to perform userspace tracing is currently to write
	504	an string to /mnt/debugfs/ltt/write_event. See <a
	505	href="#userspacetracing">Userspace tracing</a> in the
	506	installation for sources section of this document.
	507
	508	<hr />
	509
	510	<h2><a href="#TOCsection4" name="section4">Creating Debian or RPM packages</a></h2>
	511	<p>
	512
	513	<li>Create custom LTTV Debian packages</li>
	514
	515	<PRE>
	516	Use : dpkg-buildpackage -rfakeroot
	517	</PRE>
	518	<p>
	519	You should then have your LTTV .deb files created for your architecture.
	520
	521	<li>Create custom LTTng packages</li>
	522	<p>
	523	For building LTTng Debian packages :
	524	get the build tree with patches applies as explained in section 2.
	525
	526	<PRE>
	527	make menuconfig (or xconfig or config) (customize your configuration)
	528	make-kpkg kernel_image
	529	</PRE>
	530	<p>
	531	You will then see your freshly created .deb in /usr/src. Install it with
	532	<PRE>
	533	dpkg -i /usr/src/(image-name).deb
	534	</PRE>
	535	<p>
	536	Then, follow the section "Editing the system wide configuration" in section 2.
	537
	538
	539
	540	</body>
	541	</html>