Display the execution times for each goal of a predicate clause

Question

I want to see the execution time inside goals of predicate with SICStus Prolog.

Example :

pred :-
   goal1,
   time         


        

Answer 1

You can use statistics/2 for that:

statistics(runtime,[Start|_]),
do_something,
statistics(runtime,[Stop|_]),
Runtime is Stop - Start.

Alternatively, you can use total_runtime instead of runtime if you want to include time for garbage collection. Start and Stop are measured in milliseconds, but the last time I used it with SICStus it returned only multiple of 10. In a project we used calls to a custom external C library to retrieve a finer resolution.

A remark to time_out/3: It is used to limit the runtime of a goal, not to measure its runtime. If the goal finishes in time, the result is success, if it needs more time the execution is aborted (internally a timeout exception is thrown) and the result is timeout.