Under package SWDP_PERFORMANCE_VERIFICATION there is a pair of reports WDT_TRACE_ON and WDT_TRACE_OFF which could switch on and switch off performance trace.
To switch on trace, set the user parameter WDA_PERF_TRACE_ON as abap_true, then run report WDT_TRACE_ON.
In the webdynpro runtime framework code,you could see there is code to record the runtime performance information implemented via keyword GET RUN TIME FIELD.
You can find all positions where framework has done such performance recording with the help of report RS_ABAP_SOURCE_SCAN with search keyword name = macro name wdr_perf_trace_on and search package name = SWDP_RUNTIME_CORE.
Once you activate the performance trace, you can run your application in UI as usual. After application runs over, you can deactivate the trace by running report WDT_TRACE_OFF, it will retrieve all runtime performance trace information with start and stop time.
the report will also do some calculations based on those two times and display the result:
For description of each columns, please refer to description maintained in DDIC structure STRC_S_STAT.