The DBUG Package Scope Global Dynamic No SET_VAR  Hint Applies No Type Boolean Default Value OFF Command-Line Format --lock-order-trace-missing- unlock[={OFF|ON}] Introduced 8.0.17 System Variable lock_order_trace_missing_unlock Scope Global Dynamic No SET_VAR  Hint Applies No Type Boolean Default Value ON Whether the LOCK_ORDER tool prints a trace in the log file when it encounters an object that is not properly instrumented with the Performance Schema. • lock_order_trace_missing_unlock Whether the LOCK_ORDER tool prints a trace in the log file when it encounters a lock that is destroyed while still held. 5.9.4 The DBUG Package The MySQL server and most MySQL clients are compiled with the DBUG package originally created by Fred Fish. When you have configured MySQL for debugging, this package makes it possible to get a trace file of what the program is doing. See Section 5.9.1.2, “Creating Trace Files” . This section summarizes the argument values that you can specify in debug options on the command line for MySQL programs that have been built with debugging support. The DBUG package can be used by invoking a program with the  --debug[= debug_options ]  or  -# [ debug_options ]  option. If you specify the  --debug  or  -#  option without a  debug_options  value, most MySQL programs use a default value. The server default is  d:t:i:o,/tmp/mysqld.trace  on Unix and  d:t:i:O,\mysqld.trace  on Windows. The effect of this default is: Most client programs use a default  debug_options  value of  d:t:o,/tmp/ program_name .trace , regardless of platform. Here are some example debug control strings as they might be specified on a shell command line: --debug=d:t 1165 • d : Enable output for all debug macros • t : Trace function calls and exits • i : Add PID to output lines • o,/tmp/mysqld.trace ,  O,\mysqld.trace : Set the debug output file.