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<title>When to use OST traces</title>
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<h2>When to use OST traces</h2>
<p>In general, it is not good idea to trace “just in case”,
or to see that everything works OK. Consider these points: </p>
<ul>
<li>Use traces to find the rough location of the problem and then use a debugger
for the rest of the job. You save time as you are able to see registers, call-stacks
and program variables. Do not debug using traces, it is very slow. </li>
<li>Some good cases to use tracing are:
<ul>
<li>in code that manages error situations, </li>
<li>initialization or stopping of operation, </li>
<li>control operations that happen rarely (user input, for example). </li>
</ul>
</li>
<li>It is not recommended to add traces to code that is called very often,
as each software tracepoint causes performance overhead. When tracepoint is
not activated, some time is spent for checking if the trace is activated or
not. When tracepoint is activated, additional time is taken when sending it
to the trace port.</li>
<li>If you get error reports after your code has been submitted to the release,
well-planned traces can help you find out what went wrong and where to start
looking for the problem. You can even instruct the problem reporter to take
additional trace log with certain tracepoints enabled: <i>“Send us a
log where tracegroups X and Y from component Z are activated.” </i></li>
</ul>
<h5>Related concepts</h5>
<ul>
<li><a href="trace_format.htm">Trace formats</a></li>
</ul>
<h5>Related tasks</h5>
<ul>
<li><a href="../tasks/connect.htm">Connecting to the trace source</a></li>
<li><a href="../tasks/decoding_traces.htm">Decoding binary traces with a Dictionary file</a></li>
<li><a href="../tasks/traceactivation.htm">Activating traces</a></li>
</ul>
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