LTTngManual.html

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   4   <title>Linux Trace Toolkit Next Generation Manual</title>
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   7
   8 <h1>Linux Trace Toolkit Next Generation Manual</h1>
   9
  10 Author : Mathieu Desnoyers, September 2005<br>
  11 Last update : January 30, 2010<br>
  12 (originally known as the LTTng QUICKSTART guide)
  13
  14 <h2>Table of Contents</h2>
  15
  16 <ul>
  17 <li><a href="#intro" name="TOCintro">Introduction</a></li>
  18 <ul>
  19 <li><a href="#licenses" name="TOClicenses">Licenses</a></li>
  20 <ul>
  21 <li><a href="#arch" name="TOCarch">Supported architectures</a></li>
  22 </ul>
  23
  24 <li><a href="#section1" name="TOCsection1">Installing LTTng and LTTV from
  25 sources</a></li>
  26 <ul>
  27 <li><a href="#prerequisites" name="TOCprerequisites">Prerequisistes</li>
  28 <li><a href="#getlttng" name="TOCgetlttng">Getting the LTTng packages</li>
  29 <li><a href="#getlttngsrc" name="TOCgetlttngsrc">Getting the LTTng kernel sources</li>
  30 <li><a href="#installlttng" name="TOCinstalllttng">Installing a LTTng kernel</li>
  31 <li><a href="#editconfig" name="TOCeditconfig">Editing the system wide
  32 configuration</a>
  33 <li><a href="#getlttctl" name="TOCgetlttctl">Getting and installing the
  34 ltt-control package</li>
  35 <li><a href="#userspacetracing" name="TOCuserspacetracing">Userspace Tracing</li>
  36 <li><a href="#getlttv" name="TOCgetlttv">Getting and installing the LTTV package</ul>
  37
  38 <li><a href="#section2" name="TOCsection2">Using LTTng and LTTV</a></li>
  39 <ul>
  40 <li><a href="#uselttvgui" name="TOCuselttvgui">Use graphical LTTV to control
  41 tracing and analyse traces</a></li>
  42 <li><a href="#uselttngtext" name="TOCuselttngtext">Use text mode LTTng to
  43 control tracing</a></li>
  44 <li><a href="#uselttvtext" name="TOCuselttvtext">Use text mode LTTV</a></li>
  45 <li><a href="#hybrid" name="TOChybrid">Tracing in "Hybrid" mode</a></li>
  46 <li><a href="#flight" name="TOCflight">Tracing in flight recorder mode</a></li>
  47 </ul>
  48
  49 <li><a href="#section3" name="TOCsection3">Adding kernel and user-space
  50 instrumentation</a>
  51 <ul>
  52 <li><a href="#kerneltp" name="TOCkerneltp">Adding kernel instrumentation</a></li>
  53 <li><a href="#usertp" name="TOCusertp">Adding userspace instrumentation</a></li>
  54 </ul>
  55
  56 <li><a href="#section4" name="TOCsection4">Creating Debian and RPM packages
  57 from LTTV</a></li>
  58 <ul>
  59 <li><a href="#pkgdebian" name="TOCpkgdebian">Create custom LTTV Debian
  60 <li><a href="#pkglttng" name="TOCpkglttng">Create custom LTTng packages</a></li>
  61 </ul>
  62
  63 </ul>
  64
  65 <hr />
  66
  67 <h2><a href="#TOCintro" name="intro">Introduction</a></h2>
  68 <p>
  69 This document is made of five parts : the first one explains how
  70 to install LTTng and LTTV from sources, the second one describes the steps
  71 to follow to trace a system and view it. The third part explains
  72 briefly how to add a new trace point to the kernel and to user space
  73 applications. The fourth and last part explains how to create Debian or RPM
  74 packages from the LTTng and LTTV sources.
  75 <p>
  76 These operations are made for installing the LTTng 0.86 tracer on a linux 2.6.X
  77 kernel. You will also find instructions for installation of LTTV 0.12.x : the
  78 Linux Trace Toolkit Viewer.
  79 To see the list of compatibilities between LTTng, ltt-control, LTTV, please
  80 refer to :
  81 <a
  82 href="http://lttng.org/cgi-bin/gitweb.cgi?p=lttv.git;a=blob_plain;f=doc/developer/lttng-lttv-compatibility.html;hb=HEAD">LTTng+LTTV versions compatibility</a>
  83
  84 The ongoing work had the Linux Kernel Markers integrated in the mainline Linux
  85 kernel since Linux 2.6.24 and the Tracepoints since 2.6.28. In its current
  86 state, the lttng patchset is necessary to have the trace clocksource, the
  87 instrumentation and the LTTng high-speed data extraction mechanism added to the
  88 kernel.
  89
  90 <br>
  91 <br>
  92 <h3><a href="#TOClicenses" name="licenses">Licenses</a></h3>
  93 <p>
  94 LTTng, UST and LTTV are developed by an open community. LTTng is released under
  95 a dual Gnu LGPLv2.1/GPLv2 license, except for very few kernel-specific files
  96 which are derived work from the Linux kernel.
  97 <p>
  98 LTTV is available under the Gnu GPLv2. The low-level LTTV trace reading library
  99 is released under Gnu LGPLv2.1.
 100 <p>
 101 The Eclipse LTTng trace analysis tool is released under the EPL and uses the
 102 LTTV trace reading library (LGPLv2.1).
 103 <p>
 104 The UST (Userspace Tracing) and the Userspace RCU libraries are released under
 105 the LGPLv2.1 license, which allows linking with non-GPL (BSD, proprietary...)
 106 applications. The associated headers are released under MIT-style/BSD-style
 107 licenses.
 108 <p>
 109 Please refer to each particular file licensing for details.
 110
 111 <h3><a href="#TOCarch" name="arch">Supported architectures</a></h3>
 112 LTTng :<br>
 113 <br>
 114 <li> x86 32/64 bits
 115 <li> PowerPC 32 and 64 bits
 116 <li> ARMv7 OMAP3
 117 <li> Other ARM (with limited timestamping precision, e.g. 1HZ. Need
 118 architecture-specific support for better precision)
 119 <li> MIPS
 120 <li> sh (partial architecture-specific instrumentation)
 121 <li> sparc64 (partial architecture-specific instrumentation)
 122 <li> s390 (partial architecture-specific instrumentation)
 123 <li> Other architectures supported without architecture-specific instrumentation
 124 and with low-resolution timestamps.<br>
 125 <br>
 126 <br>
 127 LTTV :<br>
 128 <br>
 129 <li> Intel 32/64 bits
 130 <li> PowerPC 32 and 64 bits
 131 <li> Possibly others. Takes care of endianness and type size difference between
 132 the LTTng traces and the LTTV analysis tool.
 133
 134 <hr />
 135
 136
 137 <h2><a href="#TOCsection1" name="section1">Installation from sources</a></h2>
 138 <p>
 139
 140 <h3><a href="#TOCprerequisites" name="prerequisites">Prerequisites</a></h3>
 141 <ul>
 142 <p>
 143 Tools needed to follow the package download steps :
 144
 145 <li>wget
 146 <li>bzip2
 147 <li>gzip
 148 <li>tar
 149
 150 <p>
 151 You have to install the standard development libraries and programs necessary
 152 to compile a kernel :
 153
 154 <PRE>
 155 (from Documentation/Changes in the Linux kernel tree)
 156 Gnu C                2.95.3                # gcc --version
 157 Gnu make             3.79.1                # make --version
 158 binutils             2.12                  # ld -v
 159 util-linux           2.10o                 # fdformat --version
 160 module-init-tools    0.9.10                # depmod -V
 161 </PRE>
 162
 163 <p>
 164 You might also want to have libncurses5 to have the text mode kernel
 165 configuration menu, but there are alternatives.
 166
 167 <p>
 168 Prerequisites for LTTV 0.x.x installation are :
 169
 170 <PRE>
 171 gcc 3.2 or better
 172 gtk 2.4 or better development libraries
 173   (Debian : libgtk2.0, libgtk2.0-dev)
 174   (Fedora : gtk2, gtk2-devel)
 175   note : For Fedora users : this might require at least core 3 from Fedora,
 176   or you might have to compile your own GTK2 library.
 177 glib 2.16 or better development libraries
 178   (Debian : libglib2.0-0, libglib2.0-dev)
 179   (Fedora : glib2, glib2-devel)
 180 libpopt development libraries
 181   (Debian : libpopt0, libpopt-dev)
 182   (Fedora : popt)
 183 libpango development libraries
 184   (Debian : libpango1.0, libpango1.0-dev)
 185   (Fedora : pango, pango-devel)
 186 libc6 development librairies
 187   (Debian : libc6, libc6-dev)
 188   (Fedora : glibc, glibc)
 189 </PRE>
 190 </ul>
 191
 192 <li>Reminder</li>
 193
 194 <p>
 195 See the list of compatibilities between LTTng, ltt-control and LTTV at :
 196 <a
 197 href="http://lttng.org/cgi-bin/gitweb.cgi?p=lttv.git;a=blob_plain;f=doc/developer/lttng-lttv-compatibility.html;hb=HEAD">LTTng+LTTV versions compatibility</a>.
 198
 199
 200 <h3><a href="#TOCgetlttng" name="getlttng">Getting the LTTng packages</a></h3>
 201
 202 <PRE>
 203 su -
 204 mkdir /usr/src/lttng
 205 cd /usr/src/lttng
 206 (see http://ltt.polymtl.ca/lttng for package listing)
 207 wget http://ltt.polymtl.ca/lttng/patch-2.6.X-lttng-0.x.xx.tar.bz2
 208 bzip2 -cd patch-2.6.X-lttng-0.x.xx.tar.bz2 | tar xvof -
 209 </PRE>
 210
 211
 212 <h3><a href="#TOCgetlttngsrc" name="getlttngsrc">Getting LTTng kernel sources</a></h3>
 213
 214 <PRE>
 215 su -
 216 cd /usr/src
 217 wget http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.X.tar.bz2
 218 bzip2 -cd linux-2.6.X.tar.bz2 | tar xvof -
 219 cd linux-2.6.X
 220 - For LTTng 0.9.4- cat /usr/src/lttng/patch*-2.6.X-lttng-0.x.xx* | patch -p1
 221 - For LTTng 0.9.5+ apply the patches in the order specified in the series file,
 222   or use quilt
 223 cd ..
 224 mv linux-2.6.X linux-2.6.X-lttng-0.x.xx
 225 </PRE>
 226
 227
 228 <h3><a href="#TOCinstalllttng" name="installlttng">Installing a LTTng kernel</a></h3>
 229
 230 <PRE>
 231 su -
 232 cd /usr/src/linux-2.6.X-lttng-0.x.xx
 233 make menuconfig (or make xconfig or make config)
 234     Select the &lt; Help &gt; button if you are not familiar with kernel
 235     configuration.
 236     Items preceded by [*] means they has to be built into the kernel.
 237     Items preceded by [M] means they has to be built as modules.
 238     Items preceded by [ ] means they should be removed.
 239   go to the "General setup" section
 240     Select the following options :
 241     [*] Prompt for development and/or incomplete code/drivers
 242     [*] Activate markers
 243     [*] Activate userspace markers ABI (experimental, optional)
 244     [*] Immediate value optimization (optional)
 245     [*] Linux Trace Toolkit Next Generation (LTTng) ---&gt;
 246     &lt;M&gt; or &lt;*&gt; Compile lttng tracing probes
 247     &lt;M&gt; or &lt;*&gt; Linux Trace Toolkit High-speed Lockless Data Relay
 248     &lt;M&gt; or &lt;*&gt; Linux Trace Toolkit Lock-Protected Data Relay
 249     &lt;M&gt; or &lt;*&gt; Linux Trace Toolkit Serializer
 250     &lt;M&gt; or &lt;*&gt;   Linux Trace Toolkit Marker Control
 251     &lt;M&gt; or &lt;*&gt;     Linux Trace Toolkit Tracer
 252     [*] Align Linux Trace Toolkit Traces
 253     &lt;M&gt; or &lt;*&gt; Support logging events from userspace
 254     [*] Support trace extraction from crash dump
 255     &lt;M&gt; or &lt;*&gt; Linux Trace Toolkit Trace Controller
 256     &lt;M&gt; or &lt;*&gt; Linux Trace Toolkit State Dump
 257   Select &lt;Exit&gt;
 258   Select &lt;Exit&gt;
 259   Select &lt;Yes&gt;
 260 make
 261 make modules_install
 262 (if necessary, create a initrd with mkinitrd or your preferate alternative)
 263 (mkinitrd -o /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx)
 264
 265 -- on X86, X86_64
 266 make install
 267 reboot
 268 Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
 269
 270 -- on PowerPC
 271 cp vmlinux.strip /boot/vmlinux-2.6.X-lttng-0.x.xx
 272 cp System.map /boot/System.map-2.6.X-lttng-0.x.xx
 273 cp .config /boot/config-2.6.X-lttng-0.x.xx
 274 depmod -ae -F /boot/System.map-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
 275 mkinitrd /boot/initrd.img-2.6.X-lttng-0.x.xx 2.6.X-lttng-0.x.xx
 276 (edit /etc/yaboot.conf to add a new entry pointing to your kernel : the entry
 277 that comes first is the default kernel)
 278 ybin
 279 select the right entry at the yaboot prompt (see choices : tab, select : type
 280 the kernel name followed by enter)
 281 Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
 282 --
 283 </PRE>
 284
 285 <h3><a href="#TOCeditconfig" name="editconfig">Editing the system wide
 286 configuration</a></h3>
 287
 288 <p>
 289 You must activate debugfs and specify a mount point. This is typically done in
 290 fstab such that it happens at boot time.  If you have never used DebugFS before,
 291 these operation would do this for you :
 292
 293 <PRE>
 294 mkdir /mnt/debugfs
 295 cp /etc/fstab /etc/fstab.lttng.bkp
 296 echo "debugfs         /mnt/debugfs    debugfs rw              0       0"  >> /etc/fstab
 297 </PRE>
 298
 299 <p>
 300 then, rebooting or issuing the following command will activate debugfs :
 301 <PRE>
 302 mount /mnt/debugfs
 303 </PRE>
 304
 305 <p>
 306 You need to load the LTT modules to be able to control tracing from user
 307 space. This is done by issuing the following commands. Note however
 308 these commands load all LTT modules. Depending on what options you chose to
 309 compile statically, you may not need to issue all these commands.
 310
 311 <PRE>
 312 modprobe ltt-trace-control
 313 modprobe ltt-marker-control
 314 modprobe ltt-tracer
 315 modprobe ltt-serialize
 316 modprobe ltt-relay
 317 modprobe ipc-trace
 318 modprobe kernel-trace
 319 modprobe mm-trace
 320 modprobe net-trace
 321 modprobe fs-trace
 322 modprobe jbd2-trace
 323 modprobe ext4-trace
 324 modprobe syscall-trace
 325 modprobe trap-trace
 326 #if locking tracing is wanted, uncomment the following
 327 #modprobe lockdep-trace
 328 </PRE>
 329
 330 <p>
 331 If you want to have complete information about the kernel state (including all
 332 the process names), you need to load the ltt-statedump module. This is done by
 333 issuing the command :
 334
 335 <PRE>
 336 modprobe ltt-statedump
 337 </PRE>
 338 <p>
 339 You can automate at boot time loading the ltt-control module by :
 340
 341 <PRE>
 342 cp /etc/modules /etc/modules.bkp
 343 echo ltt-trace-control >> /etc/modules
 344 echo ltt-marker-control >> /etc/modules
 345 echo ltt-tracer >> /etc/modules
 346 echo ltt-serialize >> /etc/modules
 347 echo ltt-relay >> /etc/modules
 348 echo ipc-trace >> /etc/modules
 349 echo kernel-trace >> /etc/modules
 350 echo mm-trace >> /etc/modules
 351 echo net-trace >> /etc/modules
 352 echo fs-trace >> /etc/modules
 353 echo jbd2-trace >> /etc/modules
 354 echo ext4-trace >> /etc/modules
 355 echo syscall-trace >> /etc/modules
 356 echo trap-trace >> /etc/modules
 357 #if locking tracing is wanted, uncomment the following
 358 #echo lockdep-trace >> /etc/modules
 359 </PRE>
 360
 361
 362 <h3><a href="#TOCgetlttctl" name="getlttctl">Getting and installing the
 363 ltt-control package (on the traced machine)</a></h3>
 364 <p>
 365 (note : the ltt-control package contains lttd and lttctl. Although it has the
 366 same name as the ltt-control kernel module, they are *not* the same thing.)
 367
 368 <PRE>
 369 su -
 370 cd /usr/src
 371 wget http://ltt.polymtl.ca/lttng/ltt-control-0.x-xxxx2006.tar.gz
 372 gzip -cd ltt-control-0.x-xxxx2008.tar.gz | tar xvof -
 373 cd ltt-control-0.x-xxxx2006
 374 (refer to README to see the development libraries that must be installed on you
 375 system)
 376 ./configure
 377 make
 378 make install
 379 # (run ldconfig to ensure new shared objects are taken into account)
 380 ldconfig
 381 </PRE>
 382
 383 <h3><a href="#TOCuserspacetracing" name="userspacetracing">Userspace tracing</a></h3>
 384
 385 <PRE>
 386 Make sure you selected the kernel menuconfig option :
 387     &lt;M&gt; or &lt;*&gt; Support logging events from userspace
 388 And that the ltt-userspace-event kernel module is loaded if selected as a
 389 module.
 390
 391 Simple userspace tracing is available through
 392 echo "some text to record" &gt; /mnt/debugfs/ltt/write_event
 393
 394 It will appear in the trace under event :
 395 channel : userspace
 396 event name : event
 397 </PRE>
 398
 399 <h3><a href="#TOCgetlttv" name="getlttv">Getting and installing the LTTV package
 400 (on the visualisation machine, same
 401 or different from the visualisation machine)</a></h3>
 402
 403 <PRE>
 404 su -
 405 cd /usr/src
 406 wget http://ltt.polymtl.ca/packages/lttv-0.x.xx-xxxx2008.tar.gz
 407 gzip -cd lttv-0.x.xx-xxxx2008.tar.gz | tar xvof -
 408 cd lttv-0.x.xx-xxxx2008
 409 (refer to README to see the development libraries that must be installed on your
 410 system)
 411 ./configure
 412 make
 413 make install
 414 # (run ldconfig to ensure new shared objects are taken into account)
 415 ldconfig
 416 </PRE>
 417
 418 <hr />
 419
 420
 421 <h2><a href="#TOCsection2" name="section2">Using LTTng and LTTV</a></h2>
 422
 423 <li><b>IMPORTANT : Arm Linux Kernel Markers after each boot before tracing</b></li>
 424 <PRE>
 425 ltt-armall
 426 </PRE>
 427
 428 <h3><a href="#TOCuselttvgui" name="uselttvgui">Use graphical LTTV to control
 429 tracing and analyse traces</a></h3>
 430 <PRE>
 431 lttv-gui (or /usr/local/bin/lttv-gui)
 432   - Spot the "Tracing Control" icon : click on it
 433       (it's a traffic light icon)
 434     - enter the root password
 435     - click "start"
 436     - click "stop"
 437     - Yes
 438       * You should now see a trace
 439 </PRE>
 440
 441 <h3><a href="#TOCuselttngtext" name="uselttngtext">Use text mode LTTng to control tracing</a></h3>
 442 <PRE>
 443 The tracing can be controlled from a terminal by using the lttctl command (as
 444 root).
 445
 446 Start tracing :
 447
 448 lttctl -C -w /tmp/trace1 trace1
 449
 450 Stop tracing and destroy trace channels :
 451
 452 lttctl -D trace1
 453
 454 see lttctl --help for details.
 455 </PRE>
 456 <p>
 457 (note : to see if the buffers has been filled, look at the dmesg output after
 458 lttctl -D or after stopping tracing from the GUI, it will show an event lost
 459 count. If it is the case, try using larger buffers. See lttctl --help to learn
 460 how. lttv now also shows event lost messages in the console when loading a trace
 461 with missing events or lost subbuffers.)
 462
 463 <h3><a href="#TOCuselttvtext" name="uselttvtext">Use text mode LTTV</a></h3>
 464 <p>
 465 Feel free to look in /usr/local/lib/lttv/plugins to see all the text and
 466 graphical plugins available.
 467 <p>
 468 For example, a simple trace dump in text format is available with :
 469 <PRE>
 470 lttv -m textDump -t /tmp/trace
 471 </PRE>
 472 <p>
 473 See lttv -m textDump --help for detailed command line options of textDump.
 474 <p>
 475 It is, in the current state of the project, very useful to use "grep" on the
 476 text output to filter by specific event fields. You can later copy the timestamp
 477 of the events to the clipboard and paste them in the GUI by clicking on the
 478 bottom right label "Current time". Support for this type of filtering should
 479 be added to the filter module soon.
 480
 481 <h3><a href="#TOChybrid" name="hybrid">Tracing in "Hybrid" mode</a></h3>
 482 <p>
 483 Starting from LTTng 0.5.105 and ltt-control 0.20, a new mode can be used :
 484 hybrid. It can be especially useful when studying big workloads on a long period
 485 of time.
 486 <p>
 487 When using this mode, the most important, low rate control information will be
 488 recorded during all the trace by lttd (i.e. process creation/exit). The high
 489 rate information (i.e. interrupt/traps/syscall entry/exit) will be kept in a
 490 flight recorder buffer (now named flight-channelname_X).
 491 <p>
 492 The following lttctl commands take an hybrid trace :
 493 <p>
 494 Create trace channel, start lttd on normal channels, start tracing:
 495 <PRE>
 496 lttctl -C -w /tmp/trace2 -o channel.kernel.overwrite=1 trace2
 497 </PRE>
 498 <p>
 499 Stop tracing, start lttd on flight recorder channels, destroy trace channels :
 500 <PRE>
 501 lttctl -D -w /tmp/trace2 trace2
 502 </PRE>
 503 <p>
 504 Each "overwrite" channel is flight recorder channel.
 505
 506
 507 <h3><a href="#TOCflight" name="flight">Tracing in flight recorder mode</a></h3>
 508 <li>Flight recorder mode</li>
 509 <p>
 510 The flight recorder mode writes data into overwritten buffers for all channels,
 511 including control channels, except for the facilities tracefiles. It consists of
 512 setting all channels to "overwrite".
 513 <p>
 514 The following lttctl commands take a flight recorder trace :
 515 <PRE>
 516 lttctl -C -w /tmp/trace3 -o channel.all.overwrite=1 trace3
 517 ...
 518 lttctl -D -w /tmp/trace3 trace3
 519 </PRE>
 520
 521 <hr />
 522
 523
 524 <h2><a href="#TOCsection3" name="section3">Adding new instrumentations with the
 525 markers</a></h2>
 526 <p>
 527
 528 <h3><a href="#TOCkerneltp" name="kerneltp">Adding kernel
 529 instrumentation</a></h3>
 530
 531 <p>
 532 See <a
 533 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>
 534 and <a
 535 href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=blob;f=Documentation/trace/tracepoints.txt">Documentation/trace/tracepoints.txt</a> in your kernel
 536 tree.
 537 <p>
 538 Also see <a
 539 href="http://git.kernel.org/?p=linux/kernel/git/compudj/linux-2.6-lttng.git;a=tree;f=ltt/probes">ltt/probes/</a>
 540 for LTTng probe examples.
 541
 542 <h3><a href="#TOCusertp" name="usertp">Adding userspace instrumentation</a></h3>
 543
 544 Add new events to userspace programs with
 545 <a href="http://ltt.polymtl.ca/packages/">userspace markers packages</a>.
 546 Get the latest markers-userspace-*.tar.bz2 and see the Makefile and examples. It
 547 allows inserting markers in executables and libraries, currently only on x86_32
 548 and x86_64.
 549 See <a
 550 href="http://ltt.polymtl.ca/packages/markers-userspace-0.5.tar.bz2">markers-userspace-0.5.tar.bz2</a> or more recent.
 551
 552 <p>
 553 Note that tracepoint/marker-based userspace tracing is available at <a
 554 href="http://lttng.org/ust/">LTTng User-space Tracer (UST)</a>.
 555
 556 <p>
 557 The easy quick-and-dirty way to perform userspace tracing is currently to write
 558 an string to /mnt/debugfs/ltt/write_event. See <a
 559 href="#userspacetracing">Userspace tracing</a> in the
 560 installation for sources section of this document.
 561
 562 <hr />
 563
 564 <h2><a href="#TOCsection4" name="section4">Creating Debian or RPM packages</a></h2>
 565 <p>
 566
 567 <h3><a href="#TOCpkgdebian" name="pkgdebian">Create custom LTTV Debian packages</a></h3>
 568
 569 <PRE>
 570 Use : dpkg-buildpackage -rfakeroot
 571 </PRE>
 572 <p>
 573 You should then have your LTTV .deb files created for your architecture.
 574
 575 <h3><a href="#TOCpkglttng" name="pkglttng">Create custom LTTng packages</a></h3>
 576 <p>
 577 For building LTTng Debian packages :
 578 get the build tree with patches applies as explained in section 2.
 579
 580 <PRE>
 581 make menuconfig (or xconfig or config) (customize your configuration)
 582 make-kpkg kernel_image
 583 </PRE>
 584 <p>
 585 You will then see your freshly created .deb in /usr/src. Install it with
 586 <PRE>
 587 dpkg -i /usr/src/(image-name).deb
 588 </PRE>
 589 <p>
 590 Then, follow the section "Editing the system wide configuration" in section 2.
 591
 592 <hr />
 593
 594   </body>
 595 </html>