+* ``--trace-mode=<o[verwrite] | d[iscard] >``
+
+ Specify the mode of update of trace output file. Either update on a file
+ can be wrapped or discarded when file size reaches its maximum limit.
+ For example:
+
+ To ``discard`` update on trace output file::
+
+ --trace-mode=d or --trace-mode=discard
+
+ Default mode is ``overwrite`` and parameter must be specified once only.
+