On Jan 31, 1:40 pm, Bill James <w_a_x_...@yahoo.com> wrote: > (set! *warn-on-reflection* true) > > (def buffer-size 1920000) > (def array (byte-array buffer-size)) > > (defmacro add [m n] `(unchecked-add (int ~m) (int ~n))) > (defmacro uinc [m] `(unchecked-inc ~m)) > (defmacro amove[a i j] `(aset ~a ~j (aget ~a ~i))) > > (defn java-like0 [^bytes cpu_array] > (loop [i (int 0)] > (if (< i (int buffer-size)) > (let [b (byte (aget cpu_array i)) > g (byte (aget cpu_array (unchecked-add i (int 1)))) > r (byte (aget cpu_array (unchecked-add i (int 2)))) > a (byte (aget cpu_array (unchecked-add i (int 3))))] > (aset cpu_array i a) > (aset cpu_array (unchecked-add i (int 1)) b) > (aset cpu_array (unchecked-add i (int 2)) g) > (aset cpu_array (unchecked-add i (int 3)) r) > (recur (unchecked-add i (int 4))))))) > > ;;; Make buffer-size a local. > (defn java-like1 [^bytes cpu_array] > (let [buffer-size (int buffer-size)] > (loop [i (int 0)] > (if (< i (int buffer-size)) > (let [b (byte (aget cpu_array i)) > g (byte (aget cpu_array (unchecked-add i (int 1)))) > r (byte (aget cpu_array (unchecked-add i (int 2)))) > a (byte (aget cpu_array (unchecked-add i (int 3))))] > (aset cpu_array i a) > (aset cpu_array (unchecked-add i (int 1)) b) > (aset cpu_array (unchecked-add i (int 2)) g) > (aset cpu_array (unchecked-add i (int 3)) r) > (recur (unchecked-add i (int 4)))))))) > > ;;; Move byte directly from array[i] to array[j]. > ;;; Assign index values to local variables. > ;;; Eliminate "byte" hint. > (defn java-like2 [^bytes cpu_array] > (let [buffer-size (int buffer-size)] > (loop [i (int 0)] > (if (< i buffer-size) > (let [ i2 (add i 1) > i3 (add i 2) > i4 (add i 3) > a (aget cpu_array i4) > ] > (amove cpu_array i3 i4) > (amove cpu_array i2 i3) > (amove cpu_array i i2) > (aset cpu_array i a) > (recur (add i 4))))))) > > ;;; Use unchecked-inc instead of unchecked-add. > (defn java-like3 [^bytes cpu_array] > (let [buffer-size (int buffer-size)] > (loop [i (int 0)] > (if (< i buffer-size) > (let [ i2 (uinc i) > i3 (uinc i2) > i4 (uinc i3) > a (aget cpu_array i4) > ] > (amove cpu_array i3 i4) > (amove cpu_array i2 i3) > (amove cpu_array i i2) > (aset cpu_array i a) > (recur (uinc i4))))))) > > (dotimes [i 4] > (let [func-name (str "java-like" i) > func (resolve (symbol func-name))] > (println func-name) > (dotimes [_ 7] > (time > (func array))))) > > I think it will be faster on my laptop, but for now here are > the results on a rather old desktop. > > Clojure 1.2; Java 1.5.0_07 (server); Pentium 4 3.2GHz (2 cores) > > java-like0 > "Elapsed time: 81.954298 msecs" > "Elapsed time: 24.381966 msecs" > "Elapsed time: 16.528463 msecs" > "Elapsed time: 12.656007 msecs" > "Elapsed time: 12.666522 msecs" > "Elapsed time: 13.240584 msecs" > "Elapsed time: 12.625828 msecs" > java-like1 > "Elapsed time: 56.773426 msecs" > "Elapsed time: 19.099019 msecs" > "Elapsed time: 16.669669 msecs" > "Elapsed time: 6.325035 msecs" > "Elapsed time: 6.400674 msecs" > "Elapsed time: 6.374463 msecs" > "Elapsed time: 6.266154 msecs" > java-like2 > "Elapsed time: 46.777715 msecs" > "Elapsed time: 11.840942 msecs" > "Elapsed time: 10.842774 msecs" > "Elapsed time: 5.56714 msecs" > "Elapsed time: 5.655566 msecs" > "Elapsed time: 5.611824 msecs" > "Elapsed time: 5.509589 msecs" > java-like3 > "Elapsed time: 37.785107 msecs" > "Elapsed time: 8.711968 msecs" > "Elapsed time: 8.377959 msecs" > "Elapsed time: 7.094104 msecs" > "Elapsed time: 3.637105 msecs" > "Elapsed time: 3.757499 msecs" > "Elapsed time: 3.589582 msecs"
Much faster on my laptop. Core2 Duo P8600 2.4GHz Clojure 1.2 java version "1.6.0" Java(TM) SE Runtime Environment (build 1.6.0-b105) Java HotSpot(TM) Server VM (build 1.6.0-b105, mixed mode) java-like0 "Elapsed time: 40.007319 msecs" "Elapsed time: 11.8015 msecs" "Elapsed time: 10.262477 msecs" "Elapsed time: 10.363887 msecs" "Elapsed time: 10.242364 msecs" "Elapsed time: 10.163024 msecs" "Elapsed time: 10.518935 msecs" java-like1 "Elapsed time: 36.042849 msecs" "Elapsed time: 8.833804 msecs" "Elapsed time: 8.630427 msecs" "Elapsed time: 8.084827 msecs" "Elapsed time: 8.001296 msecs" "Elapsed time: 8.166401 msecs" "Elapsed time: 8.024763 msecs" java-like2 "Elapsed time: 24.401704 msecs" "Elapsed time: 4.934146 msecs" "Elapsed time: 4.368991 msecs" "Elapsed time: 4.326248 msecs" "Elapsed time: 4.326248 msecs" "Elapsed time: 4.328203 msecs" "Elapsed time: 4.288813 msecs" java-like3 "Elapsed time: 18.028548 msecs" "Elapsed time: 1.968686 msecs" "Elapsed time: 1.94494 msecs" "Elapsed time: 0.991746 msecs" "Elapsed time: 0.942299 msecs" "Elapsed time: 0.936153 msecs" "Elapsed time: 0.935873 msecs" Less than 1 millisecond! We are the winning team! -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
