X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=2.9%2Flttng-docs-2.9.txt;h=53d575f2d1edad7c5eedf1251defe4ac67b7a281;hb=3cd5f5046bca14706abaa8362af9741f9a86128f;hp=5e22e1a04bed231964f4d9ffb3bee9738fa0cd7f;hpb=e56400495f0da9a824843ebce1f2ab19cf78aa07;p=lttng-docs.git diff --git a/2.9/lttng-docs-2.9.txt b/2.9/lttng-docs-2.9.txt index 5e22e1a..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, 20 February 2017 +v2.9, 25 February 2021 include::../common/copyright.txt[] +include::../common/warning-not-maintained.txt[] + + include::../common/welcome.txt[] @@ -98,7 +101,7 @@ New features and changes in LTTng{nbsp}{revision}: -- [role="term"] ---- -lttng add-context --kernel --type=perf:cpu:raw:r0013c:x86unhalted +$ lttng add-context --kernel --type=perf:cpu:raw:r0013c:x86unhalted ---- -- + @@ -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 @@ -330,174 +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 2 December 2016. -|==== -|Distribution |Available in releases |Alternatives - -|https://www.ubuntu.com/[Ubuntu] -|Ubuntu{nbsp}14.04 _Trusty Tahr_ and Ubuntu{nbsp}16.04 _Xenial Xerus_: -<>. -|link:/docs/v2.8#doc-ubuntu[LTTng{nbsp}2.8 for Ubuntu{nbsp}16.10 _Yakkety Yak_]. - -<> for -other Ubuntu releases. - -|https://getfedora.org/[Fedora] -|_Not available_ -|<>. - -|https://www.debian.org/[Debian] -|_Not available_ -|<>. - -|https://www.opensuse.org/[openSUSE] -|_Not available_ -|<>. - -|https://www.archlinux.org/[Arch Linux] -|<>. -| - -|https://alpinelinux.org/[Alpine Linux] -|_Not available_ -|link:/docs/v2.8#doc-alpine-linux[LTTng{nbsp}2.8 for Alpine Linux{nbsp}"edge"]. - -LTTng{nbsp}2.8 for Alpine Linux{nbsp}3.5 (not released yet). - -<> 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] -|_Not available_ -|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] -|_Not available_ -|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 - -[[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"] ----- -sudo apt-add-repository ppa:lttng/stable-2.9 -sudo apt-get update ----- --- - -. Install the main LTTng{nbsp}{revision} packages: -+ --- -[role="term"] ----- -sudo apt-get install lttng-tools -sudo apt-get install lttng-modules-dkms -sudo apt-get install liblttng-ust-dev ----- --- - -. **If you need to instrument and trace - <>**, install the LTTng-UST - Java agent: -+ --- -[role="term"] ----- -sudo apt-get install liblttng-ust-agent-java ----- --- - -. **If you need to instrument and trace - <>**, install the - LTTng-UST Python agent: -+ --- -[role="term"] ----- -sudo apt-get install python3-lttngust ----- --- - - -[[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: -+ --- -[role="term"] ----- -yaourt -S lttng-tools -yaourt -S lttng-ust -yaourt -S lttng-modules ----- --- - -. **If you need to instrument and trace <>**, install the LTTng-UST Python agent: -+ --- -[role="term"] ----- -yaourt -S python-lttngust -yaourt -S python2-lttngust ----- --- - - -[[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 @@ -519,7 +364,7 @@ To build and install LTTng{nbsp}{revision} from source: -- [role="term"] ---- -cd $(mktemp -d) && +$ 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.* && @@ -534,7 +379,7 @@ sudo depmod -a -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/lttng-ust/lttng-ust-latest-2.9.tar.bz2 && tar -xf lttng-ust-latest-2.9.tar.bz2 && cd lttng-ust-2.9.* && @@ -584,7 +429,7 @@ instrumented user application with `liblttng-ust`>>: -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/lttng-tools/lttng-tools-latest-2.9.tar.bz2 && tar -xf lttng-tools-latest-2.9.tar.bz2 && cd lttng-tools-2.9.* && @@ -622,9 +467,10 @@ This tutorial walks you through the steps to: [[tracing-the-linux-kernel]] === Trace the Linux kernel -The following command lines start with cmd:sudo because you need root -privileges to trace the Linux kernel. You can avoid using cmd:sudo if -your Unix user is a member of the <>. +The following command lines start with the `#` prompt because you need +root privileges to trace the Linux kernel. You can also trace the kernel +as a regular user if your Unix user is a member of the +<>. . Create a <> which writes its traces to dir:{/tmp/my-kernel-trace}: @@ -632,7 +478,7 @@ your Unix user is a member of the <>. -- [role="term"] ---- -sudo lttng create my-kernel-session --output=/tmp/my-kernel-trace +# lttng create my-kernel-session --output=/tmp/my-kernel-trace ---- -- @@ -641,8 +487,8 @@ sudo lttng create my-kernel-session --output=/tmp/my-kernel-trace -- [role="term"] ---- -sudo lttng list --kernel -sudo lttng list --kernel --syscall +# lttng list --kernel +# lttng list --kernel --syscall ---- -- @@ -653,8 +499,8 @@ sudo lttng list --kernel --syscall -- [role="term"] ---- -sudo lttng enable-event --kernel sched_switch,sched_process_fork -sudo lttng enable-event --kernel --syscall open,close +# lttng enable-event --kernel sched_switch,sched_process_fork +# lttng enable-event --kernel --syscall open,close ---- -- + @@ -664,7 +510,7 @@ tracepoints (this will generate a lot of data when tracing): -- [role="term"] ---- -sudo lttng enable-event --kernel --all +# lttng enable-event --kernel --all ---- -- @@ -673,7 +519,7 @@ sudo lttng enable-event --kernel --all -- [role="term"] ---- -sudo lttng start +# lttng start ---- -- @@ -685,8 +531,8 @@ sudo lttng start -- [role="term"] ---- -sudo lttng stop -sudo lttng destroy +# lttng stop +# lttng destroy ---- -- + @@ -699,7 +545,7 @@ only destroys the state of the tracing session. -- [role="term"] ---- -sudo chown -R $(whoami) /tmp/my-kernel-trace +# chown -R $(whoami) /tmp/my-kernel-trace ---- -- @@ -770,7 +616,7 @@ TRACEPOINT_EVENT( -- [role="term"] ---- -gcc -c -I. hello-tp.c +$ gcc -c -I. hello-tp.c ---- -- @@ -830,7 +676,7 @@ int main(int argc, char *argv[]) -- [role="term"] ---- -gcc -c hello.c +$ gcc -c hello.c ---- -- @@ -840,7 +686,7 @@ gcc -c hello.c -- [role="term"] ---- -gcc -o hello hello.o hello-tp.o -llttng-ust -ldl +$ gcc -o hello hello.o hello-tp.o -llttng-ust -ldl ---- -- @@ -857,7 +703,7 @@ To trace the user application: -- [role="term"] ---- -./hello world and beyond +$ ./hello world and beyond ---- -- + @@ -875,7 +721,7 @@ Press Enter to continue... -- [role="term"] ---- -lttng-sessiond --daemonize +$ lttng-sessiond --daemonize ---- -- + @@ -887,7 +733,7 @@ a service that the distribution's service manager started. -- [role="term"] ---- -lttng list --userspace +$ lttng list --userspace ---- -- + @@ -899,7 +745,7 @@ under the `./hello` process. -- [role="term"] ---- -lttng create my-user-space-session +$ lttng create my-user-space-session ---- -- @@ -909,7 +755,7 @@ lttng create my-user-space-session -- [role="term"] ---- -lttng enable-event --userspace hello_world:my_first_tracepoint +$ lttng enable-event --userspace hello_world:my_first_tracepoint ---- -- @@ -918,7 +764,7 @@ lttng enable-event --userspace hello_world:my_first_tracepoint -- [role="term"] ---- -lttng start +$ lttng start ---- -- @@ -930,8 +776,8 @@ lttng start -- [role="term"] ---- -sudo lttng stop -sudo lttng destroy +$ lttng stop +$ lttng destroy ---- -- + @@ -986,7 +832,7 @@ its path to cmd:babeltrace with no options: [role="term"] ---- -babeltrace ~/lttng-traces/my-user-space-session* +$ babeltrace ~/lttng-traces/my-user-space-session* ---- cmd:babeltrace finds all traces recursively within the given path and @@ -997,7 +843,7 @@ further filtering: [role="term"] ---- -babeltrace /tmp/my-kernel-trace | grep _switch +$ babeltrace /tmp/my-kernel-trace | grep _switch ---- You can pipe the output of cmd:babeltrace into a tool like man:wc(1) to @@ -1005,7 +851,7 @@ count the recorded events: [role="term"] ---- -babeltrace /tmp/my-kernel-trace | grep _open | wc --lines +$ babeltrace /tmp/my-kernel-trace | grep _open | wc --lines ---- @@ -1107,7 +953,7 @@ Run this script: [role="term"] ---- -python3 top5proc.py /tmp/my-kernel-trace/kernel +$ python3 top5proc.py /tmp/my-kernel-trace/kernel ---- Output example: @@ -1187,11 +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. @@ -1202,7 +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 @@ -1357,10 +1203,19 @@ 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. 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. @@ -1385,8 +1240,8 @@ to configure the sub-buffer count and size for them: * **High event throughput**: In general, prefer bigger sub-buffers to lower the risk of losing event records. + -Having bigger sub-buffers also ensures a lower sub-buffer switching -frequency. +Having bigger sub-buffers also ensures a lower +<>. + The number of sub-buffers is only meaningful if you create the channel in overwrite mode: in this case, if a sub-buffer overwrite happens, the @@ -1540,7 +1395,7 @@ 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 @@ -1575,7 +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)). @@ -1623,7 +1478,7 @@ The cmd:lttng tool has a Git-like interface: [role="term"] ---- -lttng +$ lttng ---- The <> section explores the @@ -1871,7 +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 @@ -2712,7 +2567,7 @@ To build the instrumented application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -2721,7 +2576,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o tpp.o -llttng-ust -ldl +$ gcc -o app app.o tpp.o -llttng-ust -ldl ---- -- @@ -2732,7 +2587,7 @@ To run the instrumented application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -2750,7 +2605,7 @@ To create the tracepoint provider package archive file: -- [role="term"] ---- -gcc -I. -c tpp.c +$ gcc -I. -c tpp.c ---- -- @@ -2759,7 +2614,7 @@ gcc -I. -c tpp.c -- [role="term"] ---- -ar rcs tpp.a tpp.o +$ ar rcs tpp.a tpp.o ---- -- @@ -2779,7 +2634,7 @@ To build the instrumented application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -2788,7 +2643,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o tpp.a -llttng-ust -ldl +$ gcc -o app app.o tpp.a -llttng-ust -ldl ---- -- @@ -2799,7 +2654,7 @@ To run the instrumented application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -2828,7 +2683,7 @@ To build the instrumented application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -2837,7 +2692,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -ldl -L. -ltpp +$ gcc -o app app.o -ldl -L. -ltpp ---- -- @@ -2848,7 +2703,7 @@ To run the instrumented application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -2879,7 +2734,7 @@ To build the instrumented application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -2888,7 +2743,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -ldl +$ gcc -o app app.o -ldl ---- -- @@ -2900,7 +2755,7 @@ To run the instrumented application with tracing support: -- [role="term"] ---- -LD_PRELOAD=./libtpp.so ./app +$ LD_PRELOAD=./libtpp.so ./app ---- -- @@ -2911,7 +2766,7 @@ To run the instrumented application without tracing support: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -2944,7 +2799,7 @@ To build the instrumented application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -2953,7 +2808,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -ldl +$ gcc -o app app.o -ldl ---- -- @@ -2964,7 +2819,7 @@ To run the instrumented application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -2996,7 +2851,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3005,7 +2860,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o tpp.o -llttng-ust -ldl +$ gcc -shared -o libemon.so emon.o tpp.o -llttng-ust -ldl ---- -- @@ -3016,7 +2871,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3025,7 +2880,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -L. -lemon +$ gcc -o app app.o -L. -lemon ---- -- @@ -3036,7 +2891,7 @@ To run the application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3068,7 +2923,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3077,7 +2932,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o -ldl -L. -ltpp +$ gcc -shared -o libemon.so emon.o -ldl -L. -ltpp ---- -- @@ -3088,7 +2943,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3097,7 +2952,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -L. -lemon +$ gcc -o app app.o -L. -lemon ---- -- @@ -3108,7 +2963,7 @@ To run the application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3141,7 +2996,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3150,7 +3005,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o -ldl +$ gcc -shared -o libemon.so emon.o -ldl ---- -- @@ -3161,7 +3016,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3170,7 +3025,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -L. -lemon +$ gcc -o app app.o -L. -lemon ---- -- @@ -3182,7 +3037,7 @@ To run the application with tracing support: -- [role="term"] ---- -LD_PRELOAD=./libtpp.so ./app +$ LD_PRELOAD=./libtpp.so ./app ---- -- @@ -3193,7 +3048,7 @@ To run the application without tracing support: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3228,7 +3083,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3237,7 +3092,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o -ldl +$ gcc -shared -o libemon.so emon.o -ldl ---- -- @@ -3248,7 +3103,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3257,7 +3112,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -L. -lemon +$ gcc -o app app.o -L. -lemon ---- -- @@ -3268,7 +3123,7 @@ To run the application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3302,7 +3157,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3311,7 +3166,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o -ldl -L. -ltpp +$ gcc -shared -o libemon.so emon.o -ldl -L. -ltpp ---- -- @@ -3322,7 +3177,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3331,7 +3186,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -ldl -L. -lemon +$ gcc -o app app.o -ldl -L. -lemon ---- -- @@ -3342,7 +3197,7 @@ To run the application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3377,7 +3232,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3386,7 +3241,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o -ldl +$ gcc -shared -o libemon.so emon.o -ldl ---- -- @@ -3397,7 +3252,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3406,7 +3261,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -ldl -L. -lemon +$ gcc -o app app.o -ldl -L. -lemon ---- -- @@ -3417,7 +3272,7 @@ To run the application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3450,7 +3305,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3459,7 +3314,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o -ldl +$ gcc -shared -o libemon.so emon.o -ldl ---- -- @@ -3470,7 +3325,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3479,7 +3334,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o -L. -lemon +$ gcc -o app app.o -L. -lemon ---- -- @@ -3491,7 +3346,7 @@ To run the application with tracing support: -- [role="term"] ---- -LD_PRELOAD=./libtpp.so ./app +$ LD_PRELOAD=./libtpp.so ./app ---- -- @@ -3502,7 +3357,7 @@ To run the application without tracing support: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3534,7 +3389,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3543,7 +3398,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o +$ gcc -shared -o libemon.so emon.o ---- -- @@ -3554,7 +3409,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3563,7 +3418,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -o app app.o tpp.o -llttng-ust -ldl -L. -lemon +$ gcc -o app app.o tpp.o -llttng-ust -ldl -L. -lemon ---- -- @@ -3574,7 +3429,7 @@ To run the instrumented application: -- [role="term"] ---- -./app +$ ./app ---- -- @@ -3605,7 +3460,7 @@ To build the application: -- [role="term"] ---- -gcc -c app.c +$ gcc -c app.c ---- -- @@ -3614,7 +3469,7 @@ gcc -c app.c -- [role="term"] ---- -gcc -Wl,--export-dynamic -o app app.o tpp.o \ +$ gcc -Wl,--export-dynamic -o app app.o tpp.o \ -llttng-ust -ldl ---- -- @@ -3630,7 +3485,7 @@ To build the instrumented user library: -- [role="term"] ---- -gcc -I. -fpic -c emon.c +$ gcc -I. -fpic -c emon.c ---- -- @@ -3639,7 +3494,7 @@ gcc -I. -fpic -c emon.c -- [role="term"] ---- -gcc -shared -o libemon.so emon.o +$ gcc -shared -o libemon.so emon.o ---- -- @@ -3650,7 +3505,7 @@ To run the application: -- [role="term"] ---- -./app +$ ./app ---- -- |==== @@ -3689,7 +3544,7 @@ object when you start the application. [role="term"] ---- -LD_PRELOAD=liblttng-ust-fork.so ./my-app +$ LD_PRELOAD=liblttng-ust-fork.so ./my-app ---- If your tracepoint provider package is @@ -3698,7 +3553,7 @@ shared objects in env:LD_PRELOAD: [role="term"] ---- -LD_PRELOAD=liblttng-ust-fork.so:/path/to/tp.so ./my-app +$ LD_PRELOAD=liblttng-ust-fork.so:/path/to/tp.so ./my-app ---- @@ -3712,7 +3567,7 @@ path:{liblttng-ust-fd.so} shared object when you start the application: [role="term"] ---- -LD_PRELOAD=liblttng-ust-fd.so ./my-app +$ LD_PRELOAD=liblttng-ust-fd.so ./my-app ---- Typical use cases include closing all the file descriptors after @@ -3730,7 +3585,7 @@ build an application on the command line: [role="term"] ---- -gcc -o my-app my-app.o tp.o $(pkg-config --cflags --libs lttng-ust) +$ gcc -o my-app my-app.o tp.o $(pkg-config --cflags --libs lttng-ust) ---- @@ -3755,7 +3610,7 @@ or LTTng packages: -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/urcu/userspace-rcu-latest-0.9.tar.bz2 && tar -xf userspace-rcu-latest-0.9.tar.bz2 && cd userspace-rcu-0.9.* && @@ -3782,7 +3637,7 @@ sudo ldconfig -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/lttng-ust/lttng-ust-latest-2.9.tar.bz2 && tar -xf lttng-ust-latest-2.9.tar.bz2 && cd lttng-ust-2.9.* && @@ -3807,7 +3662,7 @@ relevant 32-bit library paths, for example: [role="term"] ---- -LDFLAGS='-L/usr/lib/i386-linux-gnu -L/usr/lib32' +$ LDFLAGS='-L/usr/lib/i386-linux-gnu -L/usr/lib32' ---- ==== @@ -3817,7 +3672,7 @@ LDFLAGS='-L/usr/lib/i386-linux-gnu -L/usr/lib32' -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/lttng-tools/lttng-tools-latest-2.9.tar.bz2 && tar -xf lttng-tools-latest-2.9.tar.bz2 && cd lttng-tools-2.9.* && @@ -3841,7 +3696,7 @@ sudo ldconfig -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/lttng-tools/lttng-tools-latest-2.9.tar.bz2 && tar -xf lttng-tools-latest-2.9.tar.bz2 && cd lttng-tools-2.9.* && @@ -3868,9 +3723,9 @@ instrumented 32-bit application: -- [role="term"] ---- -gcc -m32 -c -I. hello-tp.c -gcc -m32 -c hello.c -gcc -m32 -o hello hello.o hello-tp.o \ +$ gcc -m32 -c -I. hello-tp.c +$ gcc -m32 -c hello.c +$ gcc -m32 -o hello hello.o hello-tp.o \ -L/usr/lib32 -L/usr/local/lib32 \ -Wl,-rpath,/usr/lib32,-rpath,/usr/local/lib32 \ -llttng-ust -ldl @@ -3922,7 +3777,7 @@ To use `tracef()` in your application: -- [role="term"] ---- -gcc -o app app.c -llttng-ust +$ gcc -o app app.c -llttng-ust ---- -- @@ -3934,7 +3789,7 @@ To trace the events that `tracef()` calls emit: -- [role="term"] ---- -lttng enable-event --userspace 'lttng_ust_tracef:*' +$ lttng enable-event --userspace 'lttng_ust_tracef:*' ---- -- @@ -4009,7 +3864,7 @@ See man:lttng-ust(3) for a list of available log level names. -- [role="term"] ---- -gcc -o app app.c -llttng-ust +$ gcc -o app app.c -llttng-ust ---- -- @@ -4023,7 +3878,7 @@ _as severe as_ a specific log level: -- [role="term"] ---- -lttng enable-event --userspace 'lttng_ust_tracelog:*' +$ lttng enable-event --userspace 'lttng_ust_tracelog:*' --loglevel=TRACE_WARNING ---- -- @@ -4037,7 +3892,7 @@ _specific log level_: -- [role="term"] ---- -lttng enable-event --userspace 'lttng_ust_tracelog:*' +$ lttng enable-event --userspace 'lttng_ust_tracelog:*' --loglevel-only=TRACE_INFO ---- -- @@ -4046,7 +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. @@ -4076,7 +3931,7 @@ To use a user space tracing helper with any user application: -- [role="term"] ---- -LD_PRELOAD=liblttng-ust-libc-wrapper.so my-app +$ LD_PRELOAD=liblttng-ust-libc-wrapper.so my-app ---- -- + @@ -4085,7 +3940,7 @@ You can preload more than one helper: -- [role="term"] ---- -LD_PRELOAD=liblttng-ust-libc-wrapper.so:liblttng-ust-dl.so my-app +$ LD_PRELOAD=liblttng-ust-libc-wrapper.so:liblttng-ust-dl.so my-app ---- -- @@ -4208,7 +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 @@ -4328,7 +4183,7 @@ Build this example: [role="term"] ---- -javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar Test.java +$ javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar Test.java ---- <>, @@ -4337,16 +4192,16 @@ javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jar [role="term"] ---- -lttng create -lttng enable-event --jul jello -lttng start +$ lttng create +$ lttng enable-event --jul jello +$ lttng start ---- Run the compiled class: [role="term"] ---- -java -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar:. Test +$ java -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar:. Test ---- <> and inspect the @@ -4354,8 +4209,8 @@ recorded events: [role="term"] ---- -lttng stop -lttng view +$ lttng stop +$ lttng view ---- ==== @@ -4501,7 +4356,7 @@ file): [role="term"] ---- -javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-log4j.jar:$LOG4JPATH Test.java +$ javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-log4j.jar:$LOG4JPATH Test.java ---- <>, @@ -4510,16 +4365,16 @@ javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jar [role="term"] ---- -lttng create -lttng enable-event --log4j jello -lttng start +$ lttng create +$ lttng enable-event --log4j jello +$ lttng start ---- Run the compiled class: [role="term"] ---- -java -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-log4j.jar:$LOG4JPATH:. Test +$ java -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-log4j.jar:$LOG4JPATH:. Test ---- <> and inspect the @@ -4527,8 +4382,8 @@ recorded events: [role="term"] ---- -lttng stop -lttng view +$ lttng stop +$ lttng view ---- ==== @@ -4732,7 +4587,7 @@ Build this example: [role="term"] ---- -javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar Test.java +$ javac -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar Test.java ---- <> @@ -4741,8 +4596,8 @@ and <> matching the [role="term"] ---- -lttng create -lttng enable-event --jul jello +$ lttng create +$ lttng enable-event --jul jello ---- <> to the @@ -4750,22 +4605,22 @@ JUL channel: [role="term"] ---- -lttng add-context --jul --type='$app.myRetriever:intCtx' -lttng add-context --jul --type='$app.myRetriever:strContext' +$ lttng add-context --jul --type='$app.myRetriever:intCtx' +$ lttng add-context --jul --type='$app.myRetriever:strContext' ---- <>: [role="term"] ---- -lttng start +$ lttng start ---- Run the compiled class: [role="term"] ---- -java -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar:. Test +$ java -cp /usr/share/java/jarpath/lttng-ust-agent-common.jar:/usr/share/java/jarpath/lttng-ust-agent-jul.jar:. Test ---- <> and inspect the @@ -4773,8 +4628,8 @@ recorded events: [role="term"] ---- -lttng stop -lttng view +$ lttng stop +$ lttng view ---- ==== @@ -4860,16 +4715,16 @@ tracing>>: [role="term"] ---- -lttng create -lttng enable-event --python my-logger -lttng start +$ lttng create +$ lttng enable-event --python my-logger +$ lttng start ---- Run the Python script: [role="term"] ---- -python test.py +$ python test.py ---- <> and inspect the recorded @@ -4877,8 +4732,8 @@ events: [role="term"] ---- -lttng stop -lttng view +$ lttng stop +$ lttng view ---- ==== @@ -4949,7 +4804,7 @@ mostly to instrument shell scripts: [role="term"] ---- -echo "Some message, some $variable" > /proc/lttng-logger +$ echo "Some message, some $variable" > /proc/lttng-logger ---- Any event that the LTTng logger emits is named `lttng_logger` and @@ -4995,16 +4850,16 @@ df --human-readable --print-type / > /proc/lttng-logger [role="term"] ---- -lttng create -lttng enable-event --kernel lttng_logger -lttng start +$ lttng create +$ lttng enable-event --kernel lttng_logger +$ lttng start ---- Run the Bash script: [role="term"] ---- -bash test.bash +$ bash test.bash ---- <> and inspect the recorded @@ -5012,8 +4867,8 @@ events: [role="term"] ---- -lttng stop -lttng view +$ lttng stop +$ lttng view ---- ==== @@ -5084,7 +4939,7 @@ is your subsystem's name. -- [role="term"] ---- -cd $(mktemp -d) && +$ cd $(mktemp -d) && wget http://lttng.org/files/lttng-modules/lttng-modules-latest-2.9.tar.bz2 && tar -xf lttng-modules-latest-2.9.tar.bz2 && cd lttng-modules-2.9.* @@ -5176,12 +5031,12 @@ MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." ---- -- -. Edit path:{probes/Makefile} and add your new kernel module object +. Edit path:{probes/KBuild} and add your new kernel module object next to the existing ones: + -- [source,make] -.path:{probes/Makefile} +.path:{probes/KBuild} ---- # ... @@ -5199,8 +5054,8 @@ obj-m += lttng-probe-my-subsys.o -- [role="term"] ---- -make KERNELDIR=/path/to/linux -sudo make modules_install +$ make KERNELDIR=/path/to/linux +# make modules_install && depmod -a ---- -- + @@ -5317,7 +5172,7 @@ module: ==== [role="term"] ---- -sudo lttng-sessiond --extra-kmod-probes=my_subsys,usb +# lttng-sessiond --extra-kmod-probes=my_subsys,usb ---- ==== -- @@ -5335,7 +5190,7 @@ To load _only_ a given custom probe kernel module: ==== [role="term"] ---- -sudo lttng-sessiond --kmod-probes=my_subsys,usb +# lttng-sessiond --kmod-probes=my_subsys,usb ---- ==== -- @@ -5347,7 +5202,7 @@ To confirm that a probe module is loaded: -- [role="term"] ---- -lsmod | grep lttng_probe_usb +$ lsmod | grep lttng_probe_usb ---- -- @@ -5358,7 +5213,7 @@ To unload the loaded probe modules: -- [role="term"] ---- -sudo pkill lttng-sessiond +# pkill lttng-sessiond ---- -- + @@ -5420,7 +5275,7 @@ To start a user session daemon: -- [role="term"] ---- -lttng-sessiond --daemonize +$ lttng-sessiond --daemonize ---- -- @@ -5431,7 +5286,7 @@ To start the root session daemon: -- [role="term"] ---- -sudo lttng-sessiond --daemonize +# lttng-sessiond --daemonize ---- -- @@ -5460,7 +5315,7 @@ To create a tracing session with a generated name: -- [role="term"] ---- -lttng create +$ lttng create ---- -- @@ -5474,7 +5329,7 @@ To create a tracing session with a specific name: -- [role="term"] ---- -lttng create my-session +$ lttng create my-session ---- -- + @@ -5494,7 +5349,7 @@ To output LTTng traces to a non-default location: -- [role="term"] ---- -lttng create --output=/tmp/some-directory my-session +$ lttng create my-session --output=/tmp/some-directory ---- -- @@ -5507,7 +5362,7 @@ To list all the existing tracing sessions for your Unix user: -- [role="term"] ---- -lttng list +$ lttng list ---- -- @@ -5539,7 +5394,7 @@ To change the current tracing session: -- [role="term"] ---- -lttng set-session new-session +$ lttng set-session new-session ---- -- + @@ -5557,7 +5412,7 @@ To destroy the current tracing session: -- [role="term"] ---- -lttng destroy +$ lttng destroy ---- -- @@ -5594,7 +5449,7 @@ To list the available instrumentation points: ==== [role="term"] ---- -lttng list --userspace +$ lttng list --userspace ---- ==== @@ -5602,7 +5457,7 @@ lttng list --userspace ==== [role="term"] ---- -lttng list --kernel --syscall +$ lttng list --kernel --syscall ---- ==== @@ -5706,7 +5561,7 @@ command-line options to create simple to more complex event rules. ==== [role="term"] ---- -lttng enable-event --kernel sched_switch +$ lttng enable-event --kernel sched_switch ---- ==== @@ -5714,7 +5569,7 @@ lttng enable-event --kernel sched_switch ==== [role="term"] ---- -lttng enable-event --kernel --syscall open,write,read,close +$ lttng enable-event --kernel --syscall open,write,read,close ---- ==== @@ -5722,18 +5577,18 @@ lttng enable-event --kernel --syscall open,write,read,close ==== [role="term"] ---- -lttng enable-event --kernel sched_switch --filter='prev_comm == "bash"' +$ lttng enable-event --kernel sched_switch --filter='prev_comm == "bash"' ---- [role="term"] ---- -lttng enable-event --kernel --all \ +$ lttng enable-event --kernel --all \ --filter='$ctx.tid == 1988 || $ctx.tid == 1534' ---- [role="term"] ---- -lttng enable-event --jul my_logger \ +$ lttng enable-event --jul my_logger \ --filter='$app.retriever:cur_msg_id > 3' ---- @@ -5745,7 +5600,7 @@ use man:lttng(1) from a shell. ==== [role="term"] ---- -lttng enable-event --userspace my_app:'*' --loglevel=TRACE_INFO +$ lttng enable-event --userspace my_app:'*' --loglevel=TRACE_INFO ---- IMPORTANT: Make sure to always quote the wildcard character when you @@ -5756,7 +5611,7 @@ use man:lttng(1) from a shell. ==== [role="term"] ---- -lttng enable-event --python my-app.'*' \ +$ lttng enable-event --python my-app.'*' \ --exclude='my-app.module,my-app.hello' ---- ==== @@ -5765,7 +5620,7 @@ lttng enable-event --python my-app.'*' \ ==== [role="term"] ---- -lttng enable-event --log4j --all --loglevel-only=LOG4J_WARN +$ lttng enable-event --log4j --all --loglevel-only=LOG4J_WARN ---- ==== @@ -5773,7 +5628,7 @@ lttng enable-event --log4j --all --loglevel-only=LOG4J_WARN ==== [role="term"] ---- -lttng enable-event --userspace my_app:my_tracepoint --channel=my-channel +$ lttng enable-event --userspace my_app:my_tracepoint --channel=my-channel ---- ==== @@ -5785,8 +5640,8 @@ rules: [role="term"] ---- -lttng enable-event --userspace my_app:my_tracepoint -lttng enable-event --userspace my_app:my_tracepoint \ +$ lttng enable-event --userspace my_app:my_tracepoint +$ lttng enable-event --userspace my_app:my_tracepoint \ --loglevel=TRACE_INFO ---- @@ -5810,7 +5665,7 @@ a _disabled_ event rule. ==== [role="term"] ---- -lttng disable-event --python my-logger +$ lttng disable-event --python my-logger ---- ==== @@ -5818,7 +5673,7 @@ lttng disable-event --python my-logger ==== [role="term"] ---- -lttng disable-event --jul '*' +$ lttng disable-event --jul '*' ---- ==== @@ -5831,7 +5686,7 @@ rules of a given channel. [role="term"] ---- -lttng disable-event --jul --all-events +$ lttng disable-event --jul --all-events ---- ==== @@ -5849,7 +5704,7 @@ parameters, its channels, event rules, and their attributes: -- [role="term"] ---- -lttng status +$ lttng status ---- -- + @@ -5861,7 +5716,7 @@ To get the status of any tracing session: -- [role="term"] ---- -lttng list my-session +$ lttng list my-session ---- -- + @@ -5883,7 +5738,7 @@ To start tracing in the current tracing session: -- [role="term"] ---- -lttng start +$ lttng start ---- -- @@ -5899,7 +5754,7 @@ To stop tracing in the current tracing session: -- [role="term"] ---- -lttng stop +$ lttng stop ---- -- + @@ -6024,7 +5879,7 @@ command-line options to create simple to more complex channels. ==== [role="term"] ---- -lttng enable-channel --kernel my-channel +$ lttng enable-channel --kernel my-channel ---- ==== @@ -6032,7 +5887,7 @@ lttng enable-channel --kernel my-channel ==== [role="term"] ---- -lttng enable-channel --userspace --num-subbuf=4 --subbuf-size=1M \ +$ lttng enable-channel --userspace --num-subbuf=4 --subbuf-size=1M \ --buffers-pid my-channel ---- ==== @@ -6041,7 +5896,7 @@ lttng enable-channel --userspace --num-subbuf=4 --subbuf-size=1M \ ==== [role="term"] ---- -lttng enable-channel --kernel --tracefile-count=8 \ +$ lttng enable-channel --kernel --tracefile-count=8 \ --tracefile-size=4194304 my-channel ---- ==== @@ -6050,7 +5905,7 @@ lttng enable-channel --kernel --tracefile-count=8 \ ==== [role="term"] ---- -lttng enable-channel --userspace --overwrite my-channel +$ lttng enable-channel --userspace --overwrite my-channel ---- ==== @@ -6059,8 +5914,8 @@ two different channels: [role="term"] ---- -lttng enable-event --userspace --channel=my-channel app:tp -lttng enable-event --userspace --channel=other-channel app:tp +$ lttng enable-event --userspace --channel=my-channel app:tp +$ lttng enable-event --userspace --channel=other-channel app:tp ---- If both channels are enabled, when a tracepoint named `app:tp` is @@ -6077,7 +5932,7 @@ previously, use the man:lttng-disable-channel(1) command. ==== [role="term"] ---- -lttng disable-channel --kernel my-channel +$ lttng disable-channel --kernel my-channel ---- ==== @@ -6125,7 +5980,7 @@ of the current tracing session. [role="term"] ---- -lttng add-context --userspace --type=vpid --type=perf:thread:cpu-cycles +$ lttng add-context --userspace --type=vpid --type=perf:thread:cpu-cycles ---- ==== @@ -6137,8 +5992,8 @@ man:perf-record(1). [role="term"] ---- -lttng add-context --userspace --type=perf:thread:raw:r0110:test -lttng add-context --kernel --type=perf:cpu:raw:r0013c:x86unhalted +$ lttng add-context --userspace --type=perf:thread:raw:r0110:test +$ lttng add-context --kernel --type=perf:cpu:raw:r0013c:x86unhalted ---- ==== @@ -6150,7 +6005,7 @@ tracing session. [role="term"] ---- -lttng add-context --kernel --channel=my-channel --type=tid +$ lttng add-context --kernel --channel=my-channel --type=tid ---- ==== @@ -6163,7 +6018,7 @@ in the channel named `my-channel`: [role="term"] ---- -lttng add-context --kernel --channel=my-channel \ +$ lttng add-context --kernel --channel=my-channel \ --type='$app:retriever:cur_msg_id' ---- @@ -6212,7 +6067,7 @@ tracks the specific PIDs. After: [role="term"] ---- -lttng track --pid=3,4,7,10,13 +$ lttng track --pid=3,4,7,10,13 ---- the whitelist is: @@ -6225,7 +6080,7 @@ You can add more PIDs to the whitelist afterwards: [role="term"] ---- -lttng track --pid=1,15,16 +$ lttng track --pid=1,15,16 ---- The result is: @@ -6239,7 +6094,7 @@ whitelist. Given the previous example, the following command: [role="term"] ---- -lttng untrack --pid=3,7,10,13 +$ lttng untrack --pid=3,7,10,13 ---- leads to this whitelist: @@ -6248,12 +6103,12 @@ 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"] ---- -lttng track --pid --all +$ lttng track --pid --all ---- The result is, again: @@ -6274,7 +6129,7 @@ man:lttng-untrack(1) command to clear the whitelist after you [role="term"] ---- -lttng untrack --pid --all +$ lttng untrack --pid --all ---- gives: @@ -6290,7 +6145,7 @@ specific PIDs, for example: [role="term"] ---- -lttng track --pid=6,11 +$ lttng track --pid=6,11 ---- Result: @@ -6328,7 +6183,7 @@ To save a given tracing session configuration: -- [role="term"] ---- -lttng save my-session +$ lttng save my-session ---- -- + @@ -6355,7 +6210,7 @@ To load a tracing session: -- [role="term"] ---- -lttng load my-session +$ lttng load my-session ---- -- + @@ -6383,7 +6238,7 @@ To send the trace data over the network: -- [role="term"] ---- -lttng-relayd +$ lttng-relayd ---- -- @@ -6393,7 +6248,7 @@ lttng-relayd -- [role="term"] ---- -lttng create my-session --set-url=net://remote-system +$ lttng create my-session --set-url=net://remote-system ---- -- + @@ -6402,7 +6257,7 @@ remote system. See man:lttng-create(1) for the exact URL format. . On the target system, use the man:lttng(1) command-line tool as usual. When tracing is active, the target's consumer daemon sends sub-buffers - to the relay daemon running on the remote system intead of flushing + to the relay daemon running on the remote system instead of flushing them to the local file system. The relay daemon writes the received packets to the local file system. @@ -6439,7 +6294,7 @@ To use LTTng live: -- [role="term"] ---- -lttng create --live my-session +$ lttng create my-session --live ---- -- + @@ -6451,7 +6306,8 @@ This spawns a local relay daemon. -- [role="term"] ---- -babeltrace --input-format=lttng-live net://localhost/host/hostname/my-session +$ babeltrace --input-format=lttng-live \ + net://localhost/host/hostname/my-session ---- -- + @@ -6469,7 +6325,7 @@ You can list the available live tracing sessions with Babeltrace: [role="term"] ---- -babeltrace --input-format=lttng-live net://localhost +$ babeltrace --input-format=lttng-live net://localhost ---- You can start the relay daemon on another system. In this case, you need @@ -6506,7 +6362,7 @@ To take a snapshot: -- [role="term"] ---- -lttng create --snapshot my-session +$ lttng create my-session --snapshot ---- -- + @@ -6529,7 +6385,7 @@ change before you actually take the snapshot. -- [role="term"] ---- -lttng snapshot record --name=my-first-snapshot +$ lttng snapshot record --name=my-first-snapshot ---- -- + @@ -6567,7 +6423,7 @@ XML machine interface output, for example: [role="term"] ---- -lttng --mi=xml enable-event --kernel --syscall open +$ lttng --mi=xml enable-event --kernel --syscall open ---- A schema definition (XSD) is @@ -6603,7 +6459,7 @@ To regenerate the metadata of an LTTng trace: -- [role="term"] ---- -lttng regenerate metadata +$ lttng regenerate metadata ---- -- @@ -6646,7 +6502,7 @@ create it in snapshot mode, before you take a snapshot: -- [role="term"] ---- -lttng regenerate statedump +$ lttng regenerate statedump ---- -- @@ -6655,7 +6511,7 @@ lttng regenerate statedump -- [role="term"] ---- -lttng stop +$ lttng stop ---- -- @@ -6664,7 +6520,7 @@ lttng stop -- [role="term"] ---- -lttng snapshot record --name=my-snapshot +$ lttng snapshot record --name=my-snapshot ---- -- @@ -6709,7 +6565,7 @@ trace data after a system crash: -- [role="term"] ---- -lttng create --shm-path=/path/to/shm +$ lttng create my-session --shm-path=/path/to/shm ---- -- @@ -6722,7 +6578,7 @@ lttng create --shm-path=/path/to/shm -- [role="term"] ---- -lttng-crash /path/to/shm +$ lttng-crash /path/to/shm ---- -- @@ -6737,7 +6593,7 @@ To convert the ring buffer files to LTTng trace files: -- [role="term"] ---- -lttng-crash --extract=/path/to/trace /path/to/shm +$ lttng-crash --extract=/path/to/trace /path/to/shm ---- -- @@ -7202,7 +7058,7 @@ 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. <>::