Getting Started Using the Linux Trace Toolkit

Introduction

This guide provides pointers to the information needed in the setup and configuration of the Linux Trace Toolkit (LTT) on the ST LinuxSH distribution.

The main source of information for LTT is the project's home page at Opersys Inc. There you can find the Reference Manual for LTT with an in-depth explanation of how to use it.

The standard kernel that comes with the ST distribution is already patched for LTT support and can be directly configured with tracing support. The user level tools, for both the host and the target, are included in the stm-sh4-ltt-0.9.5pre6-1.i386.rpm package.

The RPM package contains a local copy of the manual in /opt/STM/ST40Linux-1.0/devkit/sh4/target/usr/share/doc/stm-sh4-ltt-0.9.5pre6/Help.

LinuxSH hints and tips

When using the LTT on LinuxSH it is important to remember that the size of the data collected by the tracedaemon program can be big and storing it on a local filesystem (e.g. on Flash memory) can lead to a full filesystem.

Another point to remember in case your root filesystem is on NFS is that just writing the trace file will generate network traffic and consequently interrupt events that will be traced. In this case using the -p PID and -u UID options could be useful to isolate the events that are of real interest.

Once you have collected the data on the target system, it must be transferred or otherwise made readable from your development host system where it will be analyzed with the trace visualizer tracevisualizer.

Resources

• LTT Home Page
• LTT Documentation page
• RTAI - Real Time Application Interface
• Dynamic Probes for Linux