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Lesson 7

Oracle Trace Files Conclusion

In this module we have reviewed the basic functions of the Oracle trace files and their uses by Oracle technical support and the DBA. You should now be able to:
  1. Describe the functions of two types of trace files
  2. Find the location of trace files on any Oracle database
  3. Interpret information contained in trace files
  4. Create Oracle trace files to diagnose problems
  5. Set events to produce trace files

Trace Files

A trace file is created each time an Oracle instance starts or an unexpected event occurs in a user process or background process. The name of the trace file includes the instance name, the process name, and the Oracle process number. The file extension or file type is usually TRC, and, if different, is noted in your operating system-specific Oracle documentation. The contents of the trace file may include dumps of the system global area, process global area, supervisor stack, and registers. Two initialization parameters specify where the trace files are stored:
  1. BACKGROUND_DUMP_DES specifies the location for trace files created by the Oracle background processes PMON, DBWR, LGWR, and SMON.
  2. USER_DUMP_DEST specifies the location for trace files created by user processes such as SQL*Loader or Pro*C.

The Alert file also describes the location of trace files generated when internal errors occur. See the next section for a description of the Alert file. You may need to format the trace file before using it to diagnose problems. To format a trace file, use the DUMPFMT utility, which is available on most systems and is described in your operating system-specific Oracle documentation. Oracle Customer Support may ask you for a formatted trace file to help solve a problem.

New terms

Here are some terms from this module that may have been new to you:
  1. Trace file
  2. tkprof
  3. dbms_support package: Identify the session details (SID & Serial#) which we need to trace from v$session using the available information like Machine/osuser/username.
  4. oradebug:oradebug is a debugging tool that allows to inspect and change memory in the instance. The commands of this tool are executed from within SQL*Plus by prepending the commands with oradebug .
Next, you will learn to monitor Oracle events.

Trace Files - Quiz

Now, click the Quiz link below to take a quiz on this module.
Trace Files - Quiz