The LTTng Documentation
=======================
Philippe Proulx <pproulx@efficios.com>
-v2.9, 25 July 2017
+v2.9, 3 October 2017
include::../common/copyright.txt[]
applications.
[role="growable"]
-.Availability of LTTng{nbsp}{revision} for major Linux distributions as of 25 July 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,Ubuntu{nbsp}17.04 _Zesty Zapus_>>.
+|<<ubuntu,Ubuntu{nbsp}17.04 _Zesty Zapus_ and Ubuntu{nbsp}17.10 _Artful Aardvark_>>.
Ubuntu{nbsp}14.04 _Trusty Tahr_ and Ubuntu{nbsp}16.04 _Xenial Xerus_:
<<ubuntu-ppa,use the LTTng Stable{nbsp}{revision} PPA>>.
|https://getfedora.org/[Fedora]
|<<fedora,Fedora{nbsp}26>>.
-|link:/docs/v2.8#doc-fedora[LTTng{nbsp}2.8 for Fedora 25].
+|link:/docs/v2.10#doc-fedora[LTTng{nbsp}2.10 for Fedora 27].
<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
other Fedora releases.
|https://www.debian.org/[Debian]
-|xref:debian[Debian "stretch" (stable), Debian "buster" (testing),
-and Debian "sid" (unstable)].
+|<<debian,Debian "stretch" (stable)>>.
|<<building-from-source,Build LTTng{nbsp}{revision} from source>> for
other Debian releases.
|https://www.archlinux.org/[Arch Linux]
-|<<arch-linux,Latest AUR packages>>.
-|
+|_Not available_
+|link:/docs/v2.10#doc-arch-linux[LTTng{nbsp}2.10 for the current Arch Linux build].
+
+<<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{nbsp}2017.02 and Buildroot{nbsp}2017.05>>.
+|<<"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
[[ubuntu]]
=== [[ubuntu-official-repositories]]Ubuntu
-LTTng{nbsp}{revision} is available on Ubuntu{nbsp}17.04 _Zesty Zapus_.
-For previous releases of Ubuntu, <<ubuntu-ppa,use the LTTng
-Stable{nbsp}{revision} PPA>>.
+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_:
[[debian]]
=== Debian
-To install LTTng{nbsp}{revision} on Debian "stretch" (stable),
-Debian "buster" (testing), or Debian "sid" (unstable):
+To install LTTng{nbsp}{revision} on Debian "stretch" (stable):
. Install the main LTTng{nbsp}{revision} packages:
+
--
-[[arch-linux]]
-=== Arch Linux
-
-To install LTTng{nbsp}{revision} on Arch Linux using
-https://github.com/rmarquis/pacaur[pacaur]:
-
-. Install the main LTTng{nbsp}{revision} packages:
-+
---
-[role="term"]
-----
-$ pacaur -Sy lttng-tools
-$ pacaur -Sy lttng-ust
-$ pacaur -Sy lttng-modules
-----
---
-
-. **If you need to instrument and trace <<python-application,Python
- applications>>**, install the LTTng-UST Python agent:
-+
---
-[role="term"]
-----
-$ pacaur -Sy python-lttngust
-$ pacaur -Sy python2-lttngust
-----
---
-
-
[[alpine-linux]]
=== Alpine Linux
[[buildroot]]
=== Buildroot
-To install LTTng{nbsp}{revision} on Buildroot{nbsp}2017.02 or
-Buildroot{nbsp}2017.05:
+To install LTTng{nbsp}{revision} on Buildroot{nbsp}2017.02,
+Buildroot{nbsp}2017.05, or Buildroot{nbsp}2017.08:
. Launch the Buildroot configuration tool:
+
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>>::