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ocamlocaml-toplevel

OCaml: measure execution time in toplevel

How should we measure the execution time of a function in the OCaml toplevel?

Solution

  • As @user3075773 says, you can use Sys.time. However note that it returns processor time (CPU time). More often I want to know the wall clock time (elapsed time). You can get this from Unix.gettimeofday:

    let time f x =
    let t = Unix.gettimeofday () in
    let fx = f x in
    Printf.printf "execution elapsed time: %f sec\n"
        (Unix.gettimeofday () -. t);
    fx