contents/understanding-lttng/plumbing/overview.md

   1 ---
   2 id: plumbing-overview
   3 ---
   4
   5 As [mentioned previously](#doc-installing-lttng), the whole LTTng suite
   6 is made of the following packages: LTTng-tools, LTTng-UST, and
   7 LTTng-modules. Together, they provide different daemons, libraries,
   8 kernel modules and command line interfaces. The following tree shows
   9 which usable component belongs to which package:
  10
  11   * **LTTng-tools**:
  12     * session daemon (`lttng-sessiond`)
  13     * consumer daemon (`lttng-consumerd`)
  14     * relay daemon (`lttng-relayd`)
  15     * tracing control library (`liblttng-ctl`)
  16     * tracing control command line tool (`lttng`)
  17   * **LTTng-UST**:
  18     * user space tracing library (`liblttng-ust`) and its headers
  19     * preloadable user space tracing helpers
  20       (`liblttng-ust-libc-wrapper`, `liblttng-ust-pthread-wrapper`,
  21       `liblttng-ust-cyg-profile`, `liblttng-ust-cyg-profile-fast`
  22       and `liblttng-ust-dl`)
  23     * user space tracepoint code generator command line tool
  24       (`lttng-gen-tp`)
  25     * Java Util Logging tracepoint provider (`liblttng-ust-jul-jni`)
  26       and JAR file (`liblttng-ust-jul.jar`)
  27   * **LTTng-modules**:
  28     * LTTng Linux kernel tracer module
  29     * tracing ring buffer kernel modules
  30     * many LTTng probe kernel modules
  31
  32 The following diagram shows how the most important LTTng components
  33 interact. Plain black arrows represent trace data paths while dashed
  34 red arrows indicate control communications. The LTTng relay daemon is
  35 shown running on a remote system, although it could as well run on the
  36 target (monitored) system.
  37
  38 <div class="img img-90">
  39     <object data="/images/docs/plumbing.svg" type="image/svg+xml">
  40         <img src="/images/docs/plumbing.svg">
  41     </object>
  42 </div>
  43
  44 Each component is described in the following subsections.