2.8, 2.9, 2.10: since 2.8, LTTng keeps lost sub-buffer count in overwrite mode

[lttng-docs.git] / 2.8 / lttng-docs-2.8.txt

diff --git a/2.8/lttng-docs-2.8.txt b/2.8/lttng-docs-2.8.txt
index 9ff38988821008896ba057b03af3534169e69e32..80cdf9a97056b32f8016385a150844133906318a 100644 (file)
--- a/2.8/lttng-docs-2.8.txt
+++ b/2.8/lttng-docs-2.8.txt
@@ -1,12 +1,15 @@
 The LTTng Documentation
 =======================
 Philippe Proulx <pproulx@efficios.com>
-v2.8, 14 March 2017
+v2.8, 24 July 2017
 
 
 include::../common/copyright.txt[]
 
 
+include::../common/warning-not-maintained.txt[]
+
+
 include::../common/welcome.txt[]
 
 
@@ -357,6 +360,8 @@ becomes inactive or in real-time.
 [[installing-lttng]]
 == Installation
 
+include::../common/warning-installation-outdated.txt[]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
@@ -586,14 +591,14 @@ sudo depmod -a
 .Java and Python application instrumentation and tracing
 ====
 If you need to instrument and trace <<java-application,Java
-applications>> on openSUSE, you need to build and install
+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 openSUSE, you need to build and install
+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.
 ====
@@ -658,14 +663,14 @@ If you use Hob:
 .Java and Python application instrumentation and tracing
 ====
 If you need to instrument and trace <<java-application,Java
-applications>> on openSUSE, you need to build and install
+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 openSUSE, you need to build and install
+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.
 ====
@@ -1530,10 +1535,14 @@ as soon as a there's no space left for a new event record, whereas in
 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.
@@ -1713,7 +1722,7 @@ With so many similar terms, it's easy to get confused.
 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
@@ -5331,12 +5340,12 @@ MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
 ----
 --
 
-. Edit path:{probes/Makefile} and add your new kernel module object
+. Edit path:{probes/KBuild} and add your new kernel module object
   next to the existing ones:
 +
 --
 [source,make]
-.path:{probes/Makefile}
+.path:{probes/KBuild}
 ----
 # ...
 
@@ -7200,7 +7209,7 @@ event::
   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>>::