X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=trunk%2Flttv%2FQUICKSTART.html;h=8678c6d91ca77d87f5238dac15c8c50ab34d3861;hb=1aeeacdba90c3a79df5b39423c2826e7b9565f36;hp=98079c7accc37a1a67e39b68a7d161def55ecb8a;hpb=df7f63ab9e7699a88909ba141753bdaf90b95df6;p=lttv.git diff --git a/trunk/lttv/QUICKSTART.html b/trunk/lttv/QUICKSTART.html index 98079c7a..8678c6d9 100644 --- a/trunk/lttv/QUICKSTART.html +++ b/trunk/lttv/QUICKSTART.html @@ -1,26 +1,65 @@ - Linux Trace Toolkit Quickstart + Linux Trace Toolkit Next Generation User Documentation -

Linux Trace Toolkit Quickstart

Linux Trace Toolkit Next Generation User Documentation

Author : Mathieu Desnoyers, September 2005
Last update : January 21st, 2009
+(originally known as the LTTng QUICKSTART guide)

Introduction

Supported architectures

Installing LTTng and LTTV from sources

Prerequisistes

Getting the LTTng packages

Getting the LTTng kernel sources

Installing a LTTng kernel

Editing the system wide +configuration +
Getting and installing the +ltt-control package

Userspace Tracing

Getting and installing the LTTV package

Using LTTng and LTTV

Use graphical LTTV to control +tracing and analyse traces
Use text mode LTTng to +control tracing
Use text mode LTTV
Tracing in "Hybrid" mode
Tracing in flight recorder mode

Adding kernel and user-space -tracepoints

Adding kernel instrumentation
Adding userspace instrumentation

Creating Debian and RPM packages -from LTTV +from LTTV

Create custom LTTV Debian +
Create custom LTTng packages

Examples of LTTng use in the +field

Introduction

-This document is made of four parts : the first one explains how +This document is made of five parts : the first one explains how to install LTTng and LTTV from sources, the second one describes the steps to follow to trace a system and view it. The third part explains briefly how to add a new trace point to the kernel and to user space -applications. The fourth and last part explains how to create Debian or RPM -packages from the LTTng and LTTV sources. +applications. The fourth part explains how to create Debian or RPM +packages from the LTTng and LTTV sources. The fifth and last part describes use +of LTTng in the field.

These operations are made for installing the LTTng 0.86 tracer on a linux 2.6.X kernel. You will also find instructions for installation of LTTV 0.12.x : the @@ -46,17 +86,24 @@ The lttng patch is necessary to have the tracing hooks in the kernel.

-Supported architectures : +

Supported architectures

x86 32/64 bits
PowerPC 32 and 64 bits
ARM (with limited timestamping precision, e.g. 1HZ. Need architecture-specific support for better precision)
MIPS +
sh (partial architecture-specific instrumentation) +
sparc64 (partial architecture-specific instrumentation) +
s390 (partial architecture-specific instrumentation) +
Other architectures supported without architecture-specific instrumentation +and with low-resolution timestamps.

LTTV :
+
Intel 32/64 bits
PowerPC 32 and 64 bits
Possibly others. Takes care of endianness and type size difference between @@ -65,10 +112,10 @@ the LTTng traces and the LTTV analysis tool.
-
Installation from sources
+
Installation from sources

-
Prerequisites

Prerequisites

Tools needed to follow the package download steps : @@ -129,7 +176,7 @@ href="http://ltt.polymtl.ca/svn/trunk/lttv/doc/developer/lttng-lttv-compatibilit versions compatibility. -

Getting the LTTng packages

Getting the LTTng packages

 su -
@@ -141,7 +188,7 @@ bzip2 -cd patch-2.6.X-lttng-0.x.xx.tar.bz2 | tar xvof -

Getting LTTng kernel sources

Getting LTTng kernel sources

 su -
@@ -157,7 +204,7 @@ mv linux-2.6.X linux-2.6.X-lttng-0.x.xx

Installing a LTTng kernel

Installing a LTTng kernel

 su -
@@ -214,7 +261,8 @@ Select the Linux 2.6.X-lttng-0.x.xx kernel in your boot loader.
 --

Editing the system wide configuration

Editing the system wide +configuration

You must activate debugfs and specify a mount point. This is typically done in @@ -289,7 +337,9 @@ echo trap-trace >> /etc/modules #echo lockdep-trace >> /etc/modules -

Getting and installing the ltt-control package (on the traced machine)

Getting and installing the +ltt-control package (on the traced machine)

(note : the ltt-control package contains lttd and lttctl. Although it has the same name as the ltt-control kernel module, they are *not* the same thing.) @@ -307,7 +357,7 @@ make make install -

Userspace tracing

Userspace tracing

 Make sure you selected the kernel menuconfig option :
@@ -323,8 +373,9 @@ channel : userspace
 event name : event

Getting and installing the LTTV package (on the visualisation machine, same -or different from the visualisation machine)

Getting and installing the LTTV package +(on the visualisation machine, same +or different from the visualisation machine)

 su -
@@ -339,23 +390,18 @@ make
 make install

Getting and installing the markers-userspace package for user space -tracing (experimental)

-See markers-userspace-0.5.tar.bz2 or more recent. -

Using LTTng and LTTV

IMPORTANT : Arm Linux Kernel Markers after each boot
IMPORTANT : Arm Linux Kernel Markers after each boot before tracing

 ltt-armall

Use graphical LTTV to control tracing and analyse traces

Use graphical LTTV to control +tracing and analyse traces

 lttv-gui (or /usr/local/bin/lttv-gui)
   - Spot the "Tracing Control" icon : click on it
@@ -367,7 +413,7 @@ lttv-gui (or /usr/local/bin/lttv-gui)
       * You should now see a trace

Use text mode LTTng to control tracing

Use text mode LTTng to control tracing

 The tracing can be controlled from a terminal by using the lttctl command (as
 root).
@@ -389,7 +435,7 @@ count. If it is the case, try using larger buffers. See lttctl --help to learn
 how. lttv now also shows event lost messages in the console when loading a trace
 with missing events or lost subbuffers.)
 
-Use text mode LTTV
+Use text mode LTTV
 
 Feel free to look in /usr/local/lib/lttv/plugins to see all the text and
 graphical plugins available.
@@ -407,7 +453,7 @@ of the events to the clipboard and paste them in the GUI by clicking on the
 bottom right label "Current time". Support for this type of filtering should
 be added to the filter module soon.
 
-
Hybrid mode
+Tracing in "Hybrid" mode
 
 Starting from LTTng 0.5.105 and ltt-control 0.20, a new mode can be used :
 hybrid. It can be especially useful when studying big workloads on a long period
@@ -432,6 +478,8 @@ lttctl -D -w /tmp/trace2 trace2
 

 Each "overwrite" channel is flight recorder channel.
 
+
+
Tracing in flight recorder mode
 Flight recorder mode
 
 The flight recorder mode writes data into overwritten buffers for all channels,
@@ -445,45 +493,123 @@ lttctl -C -w /tmp/trace3 -o channel.all.overwrite=1 trace3
 lttctl -D -w /tmp/trace3 trace3

Adding new instrumentations with the +markers

+ +

Adding kernel +instrumentation

+See Documentation/markers.txt +and Documentation/tracepoints.txt in your kernel tree. +

+Also see ltt/probes/ +for LTTng probe examples. -* Add new events to userspace programs with userspace markers -http://ltt.polymtl.ca/packages/ +

Adding userspace instrumentation

userspace markers packages

markers-userspace-0.5.tar.bz2

+Note that a new design document for a 3rd generation of tracepoint/marker-based +userspace tracing is available at LTTng User-space Tracing +Design. This new infrastructure is not yet implemented. -* Create custom LTTV Debian packages +

+The easy quick-and-dirty way to perform userspace tracing is currently to write +an string to /mnt/debugfs/ltt/write_event. See Userspace tracing in the +installation for sources section of this document. -Use : dpkg-buildpackage -rfakeroot +

Creating Debian or RPM packages

-* Create custom LTTng packages +

Create custom LTTV Debian packages

+Use : dpkg-buildpackage -rfakeroot
+

+You should then have your LTTV .deb files created for your architecture. -Get the build tree with patches applies as explained in section 2. +

Create custom LTTng packages

+For building LTTng Debian packages : +get the build tree with patches applies as explained in section 2. +

 make menuconfig (or xconfig or config) (customize your configuration)
 make-kpkg kernel_image
-
+

You will then see your freshly created .deb in /usr/src. Install it with +

 dpkg -i /usr/src/(image-name).deb
-
+

Then, follow the section "Editing the system wide configuration" in section 2. +

Examples of LTTng use in the field

+A few examples of successful LTTng users : +

Google are deploying LTTng on their servers. They want to use it to + monitor their production servers (with flight recorder mode tracing) + and to help them solve hard to reproduce problems. They have had + success with such tracing approach to fix "rare disk delay" issues and + VM-related issues presented in this article : +
- Linux Kernel +Debugging on Google-sized clusters at Ottawa Linux + Symposium 2007 +
+
IBM Research have had problems with Commercial Scale-out applications, + which are being an increasing trend to split large server workloads. + They used LTTng successfully to solve a distributed filesystem-related + issue. It's presented in the same paper above. + +
Autodesk, in the development of their next-generation of Linux + audio/video edition applications, used LTTng extensively to solve + soft real-time issues they had. Also presented in the same paper. + +
Wind River included LTTng in their Linux distribution so their + clients, already familiar to Wind River own tracing solution in + VxWorks, car have the same kind of feature they have relied on for a + long time. + +
Montavista have integrated LTTng in their distribution for the same + reasons. It's used by Sony amongst others. + +
SuSE are currently integrating LTTng in their next SLES distribution, + because their clients asking for solutions which supports a kernel + closer to real-time need such tools to debug their problems. + +
A project between Ericsson, the Canadian Defense, NSERC and various + universities is just starting. It aims at monitoring and debugging + multi-core systems and provide automated and help user system behavior + analysis. + +
Siemens have been using LTTng internally for quite some time now. +

Linux Trace Toolkit Quickstart

Linux Trace Toolkit Next Generation User Documentation

Table of Contents