lib/perf.mal

   1 ;; Mesure performances.
   2
   3 ;; Evaluate an expression, but report the time spent
   4 (defmacro! time
   5   (fn* (exp)
   6     (let* [start (gensym)
   7            ret   (gensym)]
   8       `(let* [~start (time-ms)
   9               ~ret    ~exp]
  10         (do
  11           (prn (str "Elapsed time: " (- (time-ms) ~start) " msecs"))
  12           ~ret)))))
  13
  14 ;; Count evaluations of a function during a given time frame.
  15 (def! run-fn-for
  16
  17   (let* [
  18     run-fn-for* (fn* [fn max-ms acc-ms last-iters]
  19       (let* [start (time-ms)
  20              _ (fn)
  21              elapsed (- (time-ms) start)
  22              iters (+ 1 last-iters)
  23              new-acc-ms (+ acc-ms elapsed)]
  24         ;; (do (prn "new-acc-ms:" new-acc-ms "iters:" iters))
  25         (if (>= new-acc-ms max-ms)
  26           last-iters
  27           (run-fn-for* fn max-ms new-acc-ms iters))))
  28     ]
  29
  30     (fn* [fn max-secs]
  31       ;; fn       : function without parameters
  32       ;; max-secs : number (seconds)
  33       ;; return   : number (iterations)
  34       (do
  35         ;; Warm it up first
  36         (run-fn-for* fn 1000 0 0)
  37         ;; Now do the test
  38         (run-fn-for* fn (* 1000 max-secs) 0 0)))))
  39
  40 nil