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:
- BACKGROUND_DUMP_DES specifies the location for trace files created by the Oracle background processes PMON, DBWR, LGWR, and SMON.
- 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.
