trunk/lttv/QUICKSTART.html

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