The LTTng Documentation
=======================
Philippe Proulx <pproulx@efficios.com>
-v2.9, 14 March 2017
+v2.9, 3 October 2017
include::../common/copyright.txt[]
applications.
[role="growable"]
-.Availability of LTTng{nbsp}{revision} for major Linux distributions as of 14 March 2017.
+.Availability of LTTng{nbsp}{revision} for major Linux distributions as of 3 October 2017.
|====
|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/v2.8#doc-ubuntu[LTTng{nbsp}2.8 for Ubuntu{nbsp}16.10 _Yakkety Yak_].
-
-LTTng{nbsp}{revision} for Ubuntu{nbsp}17.04 _Zesty Zapus_ (not released
-yet).
+|<<ubuntu,Ubuntu{nbsp}17.04 _Zesty Zapus_ and Ubuntu{nbsp}17.10 _Artful Aardvark_>>.
-<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
+Ubuntu{nbsp}14.04 _Trusty Tahr_ and Ubuntu{nbsp}16.04 _Xenial Xerus_:
+<<ubuntu-ppa,use the LTTng Stable{nbsp}{revision} PPA>>.
+|<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
other Ubuntu releases.
|https://getfedora.org/[Fedora]
-|_Not available_
-|link:/docs/v2.8#doc-fedora[LTTng{nbsp}2.8 for Fedora 25].
+|<<fedora,Fedora{nbsp}26>>.
+|link:/docs/v2.10#doc-fedora[LTTng{nbsp}2.10 for Fedora 27].
-<<building-from-source,Build LTTng-modules{nbsp}{revision} from
-source>>.
+<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
+other Fedora releases.
|https://www.debian.org/[Debian]
-|<<debian,Debian "stretch" (testing) and Debian "sid" (unstable)>>.
+|xref:debian[Debian "stretch" (stable)].
|<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
other Debian releases.
-|https://www.opensuse.org/[openSUSE]
+|https://www.archlinux.org/[Arch Linux]
|_Not available_
-|<<building-from-source,Build LTTng-modules{nbsp}{revision} from
-source>>.
+|link:/docs/v2.10#doc-arch-linux[LTTng{nbsp}2.10 for the current Arch Linux build].
-|https://www.archlinux.org/[Arch Linux]
-|<<arch-linux,Latest AUR packages>>.
-|
+<<building-from-source,Build LTTng{nbsp}{revision} from source>>.
|https://alpinelinux.org/[Alpine Linux]
|<<alpine-linux,Alpine Linux "edge">>.
|
|https://buildroot.org/[Buildroot]
-|<<buildroot,Buildroot 2017.02>>.
-|link:/docs/v2.8#doc-buildroot[LTTng{nbsp}2.8 for Buildroot 2016.11].
+|xref:buildroot[Buildroot{nbsp}2017.02, Buildroot{nbsp}2017.05, and
+Buildroot{nbsp}2017.08].
+|link:/docs/v2.8#doc-buildroot[LTTng{nbsp}2.8 for Buildroot{nbsp}2016.11].
<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
other Buildroot releases.
|http://www.openembedded.org/wiki/Main_Page[OpenEmbedded] and
https://www.yoctoproject.org/[Yocto]
-|_Not available_
+|<<oe-yocto,Yocto Project{nbsp}2.3 _Pyro_>> (`openembedded-core` layer).
|link:/docs/v2.8#doc-oe-yocto[LTTng{nbsp}2.8 for Yocto Project{nbsp}2.2 _Morty_]
(`openembedded-core` layer).
-LTTng{nbsp}{revision} for Yocto Project{nbsp}2.3 _Pyro_
-(`openembedded-core` layer) (not released yet).
-
<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
other OpenEmbedded releases.
|====
[[ubuntu]]
=== [[ubuntu-official-repositories]]Ubuntu
+LTTng{nbsp}{revision} is available on Ubuntu{nbsp}17.04 _Zesty Zapus_
+and Ubuntu{nbsp}17.10 _Artful Aardvark_. For previous releases of
+Ubuntu, <<ubuntu-ppa,use the LTTng Stable{nbsp}{revision} PPA>>.
+
+To install LTTng{nbsp}{revision} on Ubuntu{nbsp}17.04 _Zesty Zapus_:
+
+. 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
+----
+--
+
+
[[ubuntu-ppa]]
==== noch:{LTTng} Stable {revision} PPA
--
-[[debian]]
-=== Debian
+[[fedora]]
+=== Fedora
-To install LTTng{nbsp}{revision} on Debian "stretch" (testing) or
-Debian "sid" (unstable):
+To install LTTng{nbsp}{revision} on Fedora{nbsp}26:
-. Install the main LTTng{nbsp}{revision} packages:
+. Install the LTTng-tools{nbsp}{revision} and LTTng-UST{nbsp}{revision}
+ packages:
+
--
[role="term"]
----
-# apt-get install lttng-modules-dkms
-# apt-get install liblttng-ust-dev
-# apt-get install lttng-tools
+# yum install lttng-tools
+# yum install lttng-ust
----
--
-. **If you need to instrument and trace <<java-application,Java
- applications>>**, install the LTTng-UST Java agent:
+. Download, build, and install the latest LTTng-modules{nbsp}{revision}:
+
--
[role="term"]
----
-# apt-get install liblttng-ust-agent-java
+$ cd $(mktemp -d) &&
+wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.9.tar.bz2 &&
+tar -xf lttng-modules-latest-2.9.tar.bz2 &&
+cd lttng-modules-2.9.* &&
+make &&
+sudo make modules_install &&
+sudo depmod -a
----
--
-. **If you need to instrument and trace <<python-application,Python
- applications>>**, install the LTTng-UST Python agent:
+[IMPORTANT]
+.Java and Python application instrumentation and tracing
+====
+If you need to instrument and trace <<java-application,Java
+applications>> on Fedora, you need to build and install
+LTTng-UST{nbsp}{revision} <<building-from-source,from source>> and pass
+the `--enable-java-agent-jul`, `--enable-java-agent-log4j`, or
+`--enable-java-agent-all` options to the `configure` script, depending
+on which Java logging framework you use.
+
+If you need to instrument and trace <<python-application,Python
+applications>> on Fedora, you need to build and install
+LTTng-UST{nbsp}{revision} from source and pass the
+`--enable-python-agent` option to the `configure` script.
+====
+
+
+[[debian]]
+=== Debian
+
+To install LTTng{nbsp}{revision} on Debian "stretch" (stable):
+
+. Install the main LTTng{nbsp}{revision} packages:
+
--
[role="term"]
----
-# apt-get install python3-lttngust
+# apt-get install lttng-modules-dkms
+# apt-get install liblttng-ust-dev
+# apt-get install lttng-tools
----
--
-
-[[arch-linux]]
-=== Arch Linux
-
-To install LTTng{nbsp}{revision} on Arch Linux using
-https://archlinux.fr/yaourt-en[Yaourt]:
-
-. Install the main LTTng{nbsp}{revision} packages:
+. **If you need to instrument and trace <<java-application,Java
+ applications>>**, install the LTTng-UST Java agent:
+
--
[role="term"]
----
-$ yaourt -S lttng-tools
-$ yaourt -S lttng-ust
-$ yaourt -S lttng-modules
+# apt-get install liblttng-ust-agent-java
----
--
--
[role="term"]
----
-$ yaourt -S python-lttngust
-$ yaourt -S python2-lttngust
+# apt-get install python3-lttngust
----
--
[role="term"]
----
$ cd $(mktemp -d) &&
-wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.8.tar.bz2 &&
-tar -xf lttng-modules-latest-2.8.tar.bz2 &&
-cd lttng-modules-2.8.* &&
+wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.9.tar.bz2 &&
+tar -xf lttng-modules-latest-2.9.tar.bz2 &&
+cd lttng-modules-2.9.* &&
make &&
sudo make modules_install &&
sudo depmod -a
[[buildroot]]
=== Buildroot
-To install LTTng{nbsp}{revision} on Buildroot{nbsp}2017.02:
+To install LTTng{nbsp}{revision} on Buildroot{nbsp}2017.02,
+Buildroot{nbsp}2017.05, or Buildroot{nbsp}2017.08:
. Launch the Buildroot configuration tool:
+
**Other**, check **lttng-libust**.
+[[oe-yocto]]
+=== OpenEmbedded and Yocto
+
+LTTng{nbsp}{revision} recipes are available in the
+http://layers.openembedded.org/layerindex/branch/master/layer/openembedded-core/[`openembedded-core`]
+layer for Yocto Project{nbsp}2.3 _Pyro_ under the following names:
+
+* `lttng-tools`
+* `lttng-modules`
+* `lttng-ust`
+
+With BitBake, the simplest way to include LTTng recipes in your target
+image is to add them to `IMAGE_INSTALL_append` in path:{conf/local.conf}:
+
+----
+IMAGE_INSTALL_append = " lttng-tools lttng-modules lttng-ust"
+----
+
+If you use Hob:
+
+. Select a machine and an image recipe.
+. Click **Edit image recipe**.
+. Under the **All recipes** tab, search for **lttng**.
+. Check the desired LTTng recipes.
+
+[IMPORTANT]
+.Java and Python application instrumentation and tracing
+====
+If you need to instrument and trace <<java-application,Java
+applications>> on Yocto/OpenEmbedded, 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 Yocto/OpenEmbedded, you need to build and install
+LTTng-UST{nbsp}{revision} from source and pass the
+`--enable-python-agent` option to the `configure` script.
+====
+
+
[[building-from-source]]
=== Build from source
discard mode, the tracer only discards the event record that doesn't
fit.
-In discard mode, LTTng increments a count of lost event records when
-an event record is lost and saves this count to the trace. In
-overwrite mode, LTTng keeps no information when it overwrites a
-sub-buffer before consuming it.
+In discard mode, LTTng increments a count of lost event records when an
+event record is lost and saves this count to the trace. In overwrite
+mode, since LTTng 2.8, LTTng increments a count of lost sub-buffers when
+a sub-buffer is lost and saves this count to the trace. In this mode,
+the exact number of lost event records in those lost sub-buffers is not
+saved to the trace. Trace analyses can use the trace's saved discarded
+event record and sub-buffer counts to decide whether or not to perform
+the analyses even if trace data is known to be missing.
There are a few ways to decrease your probability of losing event
records.
An **event** is the consequence of the execution of an _instrumentation
point_, like a tracepoint that you manually place in some source code,
or a Linux kernel KProbe. An event is said to _occur_ at a specific
-time. Different actions can be taken upon the occurance of an event,
+time. Different actions can be taken upon the occurrence of an event,
like record the event's payload to a buffer.
An **event record** is the representation of an event in a sub-buffer. A
or a Linux kernel KProbe.
+
An event is said to _occur_ at a specific time. Different actions can
-be taken upon the occurance of an event, like record the event's payload
+be taken upon the occurrence of an event, like record the event's payload
to a sub-buffer.
<<channel-overwrite-mode-vs-discard-mode,event loss mode>>::
projects / lttng-docs.git / blobdiff