About Trace Files

Oracle Database for Microsoft Windows background threads use trace files to record occurrences and exceptions of database operations, and errors.

Starting with Oracle Database 21c, the multithreaded Oracle Database model is enabled by default on Oracle Database.

In the multithreaded Oracle Database model mode, there are two types of foreground threads: static, and dynamic. The trace file name of a static foreground thread contains the name of the thread and the operating system thread ID followed by the extension ."trc" .

The following are the examples of the foreground trace file names:

• r01_ora_4537.trc

• r01_ora_6578.trc

The trace file of a dynamic thread additionally contains the operating system process ID of the Oracle Database instance such as:

• r01_ora_4568_5804.trc
• r01_ora_4568_4160.trc

The background threads in the multithreaded Oracle Database model mode are always dynamic. The following are the examples of the background trace file names:

• r01_pmon_4568_1556.trc
• r01_mmon_4568_3768.trc

When multithreaded Oracle Database model is turned off explictly, then the foreground and background threads are static. In this mode, the trace file names do not contain the OS process ID.