The LTTng Documentation
=======================
Philippe Proulx <pproulx@efficios.com>
-v2.10, 22 January 2018
+v2.10, 18 October 2019
include::../common/copyright.txt[]
+include::../common/warning-not-maintained.txt[]
+
+
include::../common/welcome.txt[]
[[installing-lttng]]
== Installation
+include::../common/warning-no-installation.txt[]
+
**LTTng** is a set of software <<plumbing,components>> which interact to
<<instrumenting,instrument>> the Linux kernel and user applications, and
to <<controlling-tracing,control tracing>> (start and stop
trace user applications.
Most distributions mark the LTTng-modules and LTTng-UST packages as
-optional when installing LTTng-tools (which is always required). In the
-following sections, we always provide the steps to install all three,
-but note that:
+optional when installing LTTng-tools (which is always required). Note
+that:
* You only need to install LTTng-modules if you intend to trace the
Linux kernel.
* You only need to install LTTng-UST if you intend to trace user
applications.
-[role="growable"]
-.Availability of LTTng{nbsp}{revision} for major Linux distributions as of 22 January 2018.
-|====
-|Distribution |Available in releases |Alternatives
-
-|https://www.ubuntu.com/[Ubuntu]
-|Ubuntu{nbsp}14.04 _Trusty Tahr_ and Ubuntu{nbsp}16.04 _Xenial Xerus_:
-<<ubuntu-ppa,use the LTTng Stable{nbsp}{revision} PPA>>.
-|link:/docs/v2.9#doc-ubuntu[LTTng{nbsp}2.9 for Ubuntu{nbsp}17.04 _Zesty Zapus_ and Ubuntu{nbsp}17.10 _Artful Aardvark_].
-
-<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
-other Ubuntu releases.
-
-|https://getfedora.org/[Fedora]
-|<<fedora,Fedora{nbsp}27>>.
-|link:/docs/v2.9#doc-fedora[LTTng{nbsp}2.9 for Fedora{nbsp}26].
-
-<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
-other Fedora releases.
-
-|https://www.debian.org/[Debian]
-|<<debian,Debian "buster" (testing) and Debian "sid" (unstable)>>.
-|link:/docs/v2.9#doc-debian[LTTng{nbsp}2.9 for Debian "stretch" (stable)].
-
-<<building-from-source,Build LTTng{nbsp}{revision} from source>>.
-
-|https://www.archlinux.org/[Arch Linux]
-|<<arch-linux,Current Arch Linux build>>.
-|<<building-from-source,Build LTTng{nbsp}{revision} from source>>.
-
-|https://alpinelinux.org/[Alpine Linux]
-|<<alpine-linux,Alpine Linux{nbsp}3.7 and Alpine Linux{nbsp}"edge">>.
-|<<building-from-source,Build LTTng{nbsp}{revision} from source>>.
-
-|https://www.redhat.com/[RHEL] and https://www.suse.com/[SLES]
-|See http://packages.efficios.com/[EfficiOS Enterprise Packages].
-|
-
-|https://buildroot.org/[Buildroot]
-|_Not available_
-|link:/docs/v2.9#doc-buildroot[LTTng{nbsp}2.9 for Buildroot{nbsp}2017.02,
-Buildroot{nbsp}2017.05, Buildroot{nbsp}2017.08, and Buildroot{nbsp}2017.11].
-
-<<building-from-source,Build LTTng{nbsp}{revision} from source>>.
-
-|http://www.openembedded.org/wiki/Main_Page[OpenEmbedded] and
-https://www.yoctoproject.org/[Yocto]
-|_Not available_
-|link:/docs/v2.9#doc-oe-yocto[LTTng{nbsp}2.9 for Yocto Project{nbsp}2.3 _Pyro_
-and Yocto Project{nbsp}2.4 _Rocko_]
-(`openembedded-core` layer).
-
-<<building-from-source,Build LTTng{nbsp}{revision} from source>>.
-|====
-
-
-[[ubuntu]]
-=== [[ubuntu-official-repositories]]Ubuntu
-
-[[ubuntu-ppa]]
-==== noch:{LTTng} Stable {revision} PPA
-
-The https://launchpad.net/~lttng/+archive/ubuntu/stable-{revision}[LTTng
-Stable{nbsp}{revision} PPA] offers the latest stable
-LTTng{nbsp}{revision} packages for:
-
-* Ubuntu{nbsp}14.04 _Trusty Tahr_
-* Ubuntu{nbsp}16.04 _Xenial Xerus_
-
-To install LTTng{nbsp}{revision} from the LTTng Stable{nbsp}{revision} PPA:
-
-. Add the LTTng Stable{nbsp}{revision} PPA repository and update the
- list of packages:
-+
---
-[role="term"]
-----
-# apt-add-repository ppa:lttng/stable-2.10
-# apt-get update
-----
---
-
-. Install the main LTTng{nbsp}{revision} packages:
-+
---
-[role="term"]
-----
-# apt-get install lttng-tools
-# apt-get install lttng-modules-dkms
-# apt-get install liblttng-ust-dev
-----
---
-
-. **If you need to instrument and trace
- <<java-application,Java applications>>**, install the LTTng-UST
- Java agent:
-+
---
-[role="term"]
-----
-# apt-get install liblttng-ust-agent-java
-----
---
-
-. **If you need to instrument and trace
- <<python-application,Python{nbsp}3 applications>>**, install the
- LTTng-UST Python agent:
-+
---
-[role="term"]
-----
-# apt-get install python3-lttngust
-----
---
-
-
-[[fedora]]
-=== Fedora
-
-To install LTTng{nbsp}{revision} on Fedora{nbsp}27:
-
-. Install the LTTng-tools{nbsp}{revision} and LTTng-UST{nbsp}{revision}
- packages:
-+
---
-[role="term"]
-----
-# yum install lttng-tools
-# yum install lttng-ust
-----
---
-
-. Download, build, and install the latest LTTng-modules{nbsp}{revision}:
-+
---
-[role="term"]
-----
-$ cd $(mktemp -d) &&
-wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.10.tar.bz2 &&
-tar -xf lttng-modules-latest-2.10.tar.bz2 &&
-cd lttng-modules-2.10.* &&
-make &&
-sudo make modules_install &&
-sudo depmod -a
-----
---
-
-[IMPORTANT]
-.Java and Python application instrumentation and tracing
-====
-If you need to instrument and trace <<java-application,Java
-applications>> on Fedora, you need to build and install
-LTTng-UST{nbsp}{revision} <<building-from-source,from source>> and pass
-the `--enable-java-agent-jul`, `--enable-java-agent-log4j`, or
-`--enable-java-agent-all` options to the `configure` script, depending
-on which Java logging framework you use.
-
-If you need to instrument and trace <<python-application,Python
-applications>> on Fedora, you need to build and install
-LTTng-UST{nbsp}{revision} from source and pass the
-`--enable-python-agent` option to the `configure` script.
-====
-
-
-[[debian]]
-=== Debian
-
-To install LTTng{nbsp}{revision} on Debian "buster" (testing)
-or Debian "sid" (unstable):
-
-. Install the main LTTng{nbsp}{revision} packages:
-+
---
-[role="term"]
-----
-# apt-get install lttng-modules-dkms
-# apt-get install liblttng-ust-dev
-# apt-get install lttng-tools
-----
---
-
-. **If you need to instrument and trace <<java-application,Java
- applications>>**, install the LTTng-UST Java agent:
-+
---
-[role="term"]
-----
-# apt-get install liblttng-ust-agent-java
-----
---
-
-. **If you need to instrument and trace <<python-application,Python
- applications>>**, install the LTTng-UST Python agent:
-+
---
-[role="term"]
-----
-# apt-get install python3-lttngust
-----
---
-
-
-[[arch-linux]]
-=== Arch Linux
-
-LTTng-UST{nbsp}{revision} is available in Arch Linux's _Community_
-repository, while LTTng-tools{nbsp}{revision} and
-LTTng-modules{nbsp}{revision} are available in the
-https://aur.archlinux.org/[AUR].
-
-To install LTTng{nbsp}{revision} on Arch Linux, using
-https://github.com/rmarquis/pacaur[pacaur] for the AUR packages:
-
-. Install the main LTTng{nbsp}{revision} packages:
-+
---
-[role="term"]
-----
-# pacman -Sy lttng-ust
-$ pacaur -Sy lttng-tools
-$ pacaur -Sy lttng-modules
-----
---
-
-. **If you need to instrument and trace <<python-application,Python
- applications>>**, install the LTTng-UST Python agent:
-+
---
-[role="term"]
-----
-# pacman -Sy python-lttngust
-# pacman -Sy python2-lttngust
-----
---
-
-
-[[alpine-linux]]
-=== Alpine Linux
-
-To install LTTng-tools{nbsp}{revision} and LTTng-UST{nbsp}{revision} on
-Alpine Linux{nbsp}3.7 or Alpine Linux{nbsp}"edge":
-
-. **If you're installing for Alpine Linux{nbsp}"edge"**, make sure your
- system is https://wiki.alpinelinux.org/wiki/Edge[configured for
- "edge"].
-. **If you're installing for Alpine Linux{nbsp}"edge"**, enable the _testing_
- repository by uncommenting the corresponding line in
- path:{/etc/apk/repositories}.
-. Add the LTTng packages:
-+
---
-[role="term"]
-----
-# apk add lttng-tools
-# apk add lttng-ust-dev
-----
---
-
-To install LTTng-modules{nbsp}{revision} (Linux kernel tracing support)
-on Alpine Linux{nbsp}3.7 or Alpine Linux{nbsp}"edge":
-
-. Add the vanilla Linux kernel:
-+
---
-[role="term"]
-----
-# apk add linux-vanilla linux-vanilla-dev
-----
---
-
-. Reboot with the vanilla Linux kernel.
-. Download, build, and install the latest LTTng-modules{nbsp}{revision}:
-+
---
-[role="term"]
-----
-$ cd $(mktemp -d) &&
-wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.10.tar.bz2 &&
-tar -xf lttng-modules-latest-2.10.tar.bz2 &&
-cd lttng-modules-2.10.* &&
-make &&
-sudo make modules_install &&
-sudo depmod -a
-----
---
-
-
-[[enterprise-distributions]]
-=== RHEL, SUSE, and other enterprise distributions
-
-To install LTTng on enterprise Linux distributions, such as Red Hat
-Enterprise Linux (RHEL) and SUSE Linux Enterprise Server (SUSE), please
-see http://packages.efficios.com/[EfficiOS Enterprise Packages].
-
[[building-from-source]]
=== Build from source
. Do some operation on your system for a few seconds. For example,
load a website, or list the files of a directory.
-. <<basic-tracing-session-control,Stop tracing>> and destroy the
+. <<creating-destroying-tracing-sessions,Destroy>> the current
tracing session:
+
--
[role="term"]
----
-# lttng stop
# lttng destroy
----
--
+
The man:lttng-destroy(1) command does not destroy the trace data; it
only destroys the state of the tracing session.
++
+The man:lttng-destroy(1) command also runs the man:lttng-stop(1) command
+implicitly (see <<basic-tracing-session-control,Start and stop a tracing
+session>>). You need to stop tracing to make LTTng flush the remaining
+trace data and make the trace readable.
. For the sake of this example, make the recorded trace accessible to
the non-root users:
. Go back to the running `hello` application and press Enter. The
program executes all `tracepoint()` instrumentation points and exits.
-. <<basic-tracing-session-control,Stop tracing>> and destroy the
+. <<creating-destroying-tracing-sessions,Destroy>> the current
tracing session:
+
--
[role="term"]
----
-$ lttng stop
$ lttng destroy
----
--
+
The man:lttng-destroy(1) command does not destroy the trace data; it
only destroys the state of the tracing session.
++
+The man:lttng-destroy(1) command also runs the man:lttng-stop(1) command
+implicitly (see <<basic-tracing-session-control,Start and stop a tracing
+session>>). You need to stop tracing to make LTTng flush the remaining
+trace data and make the trace readable.
By default, LTTng saves the traces in
+$LTTNG_HOME/lttng-traces/__name__-__date__-__time__+,
There are a few ways to decrease your probability of losing event
records.
<<channel-subbuf-size-vs-subbuf-count,Sub-buffer count and size>> shows
-how you can fine-une the sub-buffer count and size of a channel to
+how you can fine-tune the sub-buffer count and size of a channel to
virtually stop losing event records, though at the cost of greater
memory usage.
[[prebuilt-ust-helpers]]
=== Prebuilt user space tracing helpers
-The LTTng-UST package provides a few helpers in the form or preloadable
+The LTTng-UST package provides a few helpers in the form of preloadable
shared objects which automatically instrument system functions and
calls.
.LTTng-UST Java agent imported by a Java application.
image::java-app.png[]
-Note that the methods described below are new in LTTng{nbsp}{revision}.
+Note that the methods described below are new in LTTng{nbsp}2.8.
Previous LTTng versions use another technique.
NOTE: We use http://openjdk.java.net/[OpenJDK]{nbsp}8 for development
----
--
+The man:lttng-destroy(1) command also runs the man:lttng-stop(1)
+command implicitly (see <<basic-tracing-session-control,Start and stop a
+tracing session>>). You need to stop tracing to make LTTng flush the
+remaining trace data and make the trace readable.
+
[[list-instrumentation-points]]
=== List the available instrumentation points
man:lttng-start(1), warnings are printed when you run the
man:lttng-stop(1) command.
+IMPORTANT: You need to stop tracing to make LTTng flush the remaining
+trace data and make the trace readable. Note that the
+man:lttng-destroy(1) command (see
+<<creating-destroying-tracing-sessions,Create and destroy a tracing
+session>>) also runs the man:lttng-stop(1) command implicitly.
+
[[enabling-disabling-channels]]
=== Create a channel
projects / lttng-docs.git / blobdiff