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Lesson 4Background and user process trace files
ObjectiveInterpret information contained in trace files.

Background User process

Trace files are generated by the Oracle background processes (i.e. pmon, smon, dbwr) or by server processes that connect to Oracle. While trace files are primarily used by Oracle technical support, they can also be used by the DBA to diagnose problems.

Reading trace files

To illustrate, view the code below to examine the trace file.
Examine the trace file
Examine the trace file
Most trace files contain easy-to-read information about the nature of the problem.
This information is fairly easy to locate and interpret. However, many trace files contain dumps of memory and other cryptic pieces of information that are not nearly as easy to understand. Also, many trace files are much, much longer and more complex than the one shown above.

Reading trace files with tkprof

Oracle provides a tool for interrogating trace files called tkprof. This tool formats SQL session trace files so that they provide useful information in a readable format. Note that tkprof is only useful for reading trace files that are related to SQL execution.
Using tkprof to format a trace file is very simple. To see all of the features of tkprof, just enter
from the UNIX prompt:
dilbert> tkprof

Next, you will invoke tkprof. Do this by entering
tkprof trace_file_name.trc output_file_name

at the UNIX prompt. For example:
dilbert> tkprof ora_118092.trc x.lst

View the Code below to see what the output will look like.
TKProf output

Now, you will learn how to create trace files for individual sessions.
[1]TKProfTKProf is an Oracle database utility used to format SQL Trace output into human readable format. The TKProf executable is located in the ORACLE HOME/bin directory.