This variable allows you to start file tracing, without opening the debugger, for OPEN, READ, and WRITE operations.
The output is generated in the error file specified by the -e errfile runtime option.
Set this variable to a value from 1 to 9 to start tracing information; the higher the value, the more information written to file. The level of information written will differ between database types, but generally, level 1 will trace the critical information only, with more supplementary information added as a higher value is set.
The default is 0.