X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=2.9%2Flttng-docs-2.9.txt;h=53d575f2d1edad7c5eedf1251defe4ac67b7a281;hb=HEAD;hp=4a4962f9c3751eced20e830fc497cd49c6273bb5;hpb=cdb6897339cfeb5a7b280692b888d8fced808209;p=lttng-docs.git diff --git a/2.9/lttng-docs-2.9.txt b/2.9/lttng-docs-2.9.txt index 4a4962f..53d575f 100644 --- a/2.9/lttng-docs-2.9.txt +++ b/2.9/lttng-docs-2.9.txt @@ -1,12 +1,15 @@ The LTTng Documentation ======================= Philippe Proulx -v2.9, 3 October 2017 +v2.9, 25 February 2021 include::../common/copyright.txt[] +include::../common/warning-not-maintained.txt[] + + include::../common/welcome.txt[] @@ -316,6 +319,8 @@ becomes inactive or in real-time. [[installing-lttng]] == Installation +include::../common/warning-no-installation.txt[] + **LTTng** is a set of software <> which interact to <> the Linux kernel and user applications, and to <> (start and stop @@ -330,380 +335,14 @@ components are bundled into the following packages: 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 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_: -<>. -|<> for -other Ubuntu releases. - -|https://getfedora.org/[Fedora] -|<>. -|link:/docs/v2.10#doc-fedora[LTTng{nbsp}2.10 for Fedora 27]. - -<> for -other Fedora releases. - -|https://www.debian.org/[Debian] -|xref:debian[Debian "stretch" (stable)]. -|<> for -other Debian releases. - -|https://www.archlinux.org/[Arch Linux] -|_Not available_ -|link:/docs/v2.10#doc-arch-linux[LTTng{nbsp}2.10 for the current Arch Linux build]. - -<>. - -|https://alpinelinux.org/[Alpine Linux] -|<>. -|<> for -other Alpine Linux releases. - -|https://www.redhat.com/[RHEL] and https://www.suse.com/[SLES] -|See http://packages.efficios.com/[EfficiOS Enterprise Packages]. -| - -|https://buildroot.org/[Buildroot] -|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]. - -<> for -other Buildroot releases. - -|http://www.openembedded.org/wiki/Main_Page[OpenEmbedded] and -https://www.yoctoproject.org/[Yocto] -|<> (`openembedded-core` layer). -|link:/docs/v2.8#doc-oe-yocto[LTTng{nbsp}2.8 for Yocto Project{nbsp}2.2 _Morty_] -(`openembedded-core` layer). - -<> 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, <>. - -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 - <>**, install the LTTng-UST - Java agent: -+ --- -[role="term"] ----- -# apt-get install liblttng-ust-agent-java ----- --- - -. **If you need to instrument and trace - <>**, install the - LTTng-UST Python agent: -+ --- -[role="term"] ----- -# apt-get install python3-lttngust ----- --- - - -[[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-2.9 -# 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 - <>**, install the LTTng-UST - Java agent: -+ --- -[role="term"] ----- -# apt-get install liblttng-ust-agent-java ----- --- - -. **If you need to instrument and trace - <>**, install the - LTTng-UST Python agent: -+ --- -[role="term"] ----- -# apt-get install python3-lttngust ----- --- - - -[[fedora]] -=== Fedora - -To install LTTng{nbsp}{revision} on Fedora{nbsp}26: - -. 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-2.9.tar.bz2 && -tar -xf lttng-modules-latest-2.9.tar.bz2 && -cd lttng-modules-2.9.* && -make && -sudo make modules_install && -sudo depmod -a ----- --- - -[IMPORTANT] -.Java and Python application instrumentation and tracing -==== -If you need to instrument and trace <> on Fedora, you need to build and install -LTTng-UST{nbsp}{revision} <> 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 <> 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 lttng-modules-dkms -# apt-get install liblttng-ust-dev -# apt-get install lttng-tools ----- --- - -. **If you need to instrument and trace <>**, install the LTTng-UST Java agent: -+ --- -[role="term"] ----- -# apt-get install liblttng-ust-agent-java ----- --- - -. **If you need to instrument and trace <>**, install the LTTng-UST Python agent: -+ --- -[role="term"] ----- -# apt-get install python3-lttngust ----- --- - - -[[alpine-linux]] -=== Alpine Linux - -To install LTTng-tools{nbsp}{revision} and LTTng-UST{nbsp}{revision} on -Alpine Linux "edge": - -. Make sure your system is - https://wiki.alpinelinux.org/wiki/Edge[configured for "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 "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 $(mktemp -d) && -wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.9.tar.bz2 && -tar -xf lttng-modules-latest-2.9.tar.bz2 && -cd lttng-modules-2.9.* && -make && -sudo make modules_install && -sudo depmod -a ----- --- - - -[[enterprise-distributions]] -=== RHEL, SUSE, and other enterprise distributions - -To install LTTng on enterprise Linux distributions, such as Red Hat -Enterprise Linux (RHEL) and SUSE Linux Enterprise Server (SUSE), please -see http://packages.efficios.com/[EfficiOS Enterprise Packages]. - - -[[buildroot]] -=== Buildroot - -To install LTTng{nbsp}{revision} on Buildroot{nbsp}2017.02, -Buildroot{nbsp}2017.05, or Buildroot{nbsp}2017.08: - -. Launch the Buildroot configuration tool: -+ --- -[role="term"] ----- -$ make menuconfig ----- --- - -. In **Kernel**, check **Linux kernel**. -. In **Toolchain**, check **Enable WCHAR support**. -. In **Target packages**{nbsp}→ **Debugging, profiling and benchmark**, - check **lttng-modules** and **lttng-tools**. -. In **Target packages**{nbsp}→ **Libraries**{nbsp}→ - **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 <> on Yocto/OpenEmbedded, you need to build and install -LTTng-UST{nbsp}{revision} <> 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 <> 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 @@ -1394,11 +1033,11 @@ LTTng can send the generated trace data to different locations. The _tracing session mode_ dictates where to send it. The following modes are available in LTTng{nbsp}{revision}: -Local mode:: +[[local-mode]]Local mode:: LTTng writes the traces to the file system of the machine being traced (target system). -Network streaming mode:: +[[net-streaming-mode]]Network streaming mode:: LTTng sends the traces over the network to a <> running on a remote system. @@ -1409,7 +1048,7 @@ Snapshot mode:: or to send it over the network to a <> running on a remote system. -Live mode:: +[[live-mode]]Live mode:: This mode is similar to the network streaming mode, but a live trace viewer can connect to the distant relay daemon to <> by @@ -1565,13 +1204,18 @@ 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, 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. +event record is lost and saves this count to the trace. Since +LTTng{nbsp}2.8, in overwrite mode, LTTng writes to a given sub-buffer +its sequence number within its data stream. With a <>, +<>, or <> +<>, a trace reader can use such +sequence numbers to report lost packets. In overwrite mode, LTTng +doesn't write to the trace the exact number of lost event records in +those lost sub-buffers. + +Trace analyses can use saved discarded event record and sub-buffer +(packet) counts of the trace 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. @@ -1786,7 +1430,7 @@ The LTTng project incorporates: * **LTTng-tools**: Libraries and command-line interface to control tracing sessions. ** <> (man:lttng-sessiond(8)). -** <> (man:lttng-consumerd(8)). +** <> (cmd:lttng-consumerd). ** <> (man:lttng-relayd(8)). ** <> (`liblttng-ctl`). ** <> (man:lttng(1)). @@ -2082,7 +1726,7 @@ running. You can also start the session daemon manually. .The consumer daemon. image::plumbing-consumerd.png[] -The _consumer daemon_, man:lttng-consumerd(8), is a daemon which shares +The _consumer daemon_, cmd:lttng-consumerd, is a daemon which shares ring buffers with user applications or with the LTTng kernel modules to collect trace data and send it to some location (on disk or to a <> over the network). The consumer daemon @@ -4257,7 +3901,7 @@ $ lttng enable-event --userspace 'lttng_ust_tracelog:*' [[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. @@ -4419,7 +4063,7 @@ logging frameworks: .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 @@ -6459,8 +6103,8 @@ leads to this whitelist: .PIDs 3, 7, 10, and 13 are removed from the whitelist. image::track-1-4-15-16.png[] -LTTng can track all possible PIDs again using the opt:track(1):--all -option: +LTTng can track all possible PIDs again using the +opt:lttng-track(1):--all option: [role="term"] ----