Other functionality HTML traces Tracing only parts of an application with *xdebug_start_trace()* and *xdebug_stop_trace()*. Fetching the trace file name that is being used with *xdebug_get_tracefile_name()*. Changing how much data is shown with *xdebug.var_display_max_children*, *xdebug.var_display_max_data* and *xdebug.var_display_max_depth*.