bench.clj

bench.clj

(ns lazier.bench
  (:use clojure.core
        [clojure.contrib.str-utils :only (re-sub str-join)]
        clojure.contrib.pprint))

(defn slow-computation [& more]
  (Thread/sleep 500)
  (if (seq more) more 1))

(defmacro benchmark
  [functions lst]
  (println ";" (str-join "" (repeat 72 \=)))
  (pprint `~lst)
  (letfn [(make-fragment [f] `(~f ~lst))]
    `(do
       ~@(loop [functions functions timers []]
           (if (seq functions)
             (recur (rest functions)
                    (cons `(do
                             (print ";" (quote ~(first functions)) ": ")
                             (time ~(make-fragment (first functions)))
                             nil)
                          timers))
             timers))
       (println))))

concat.clj

 (list (slow-computation))
 (list (slow-computation) (slow-computation)))
; seq : "Elapsed time: 1500.213 msecs"
; next : "Elapsed time: 1500.26 msecs"
; rest : "Elapsed time: 1500.362 msecs"
; first : "Elapsed time: 1500.136 msecs"
; seq? : "Elapsed time: 1500.369 msecs"
; list? : "Elapsed time: 1500.233 msecs"
; empty? : "Elapsed time: 1500.242 msecs"
; identity : "Elapsed time: 1500.169 msecs"

dubious-results.clj

(benchmark** [identity empty? list? seq? first rest next seq]
           (concat (list (slow-computation)) 
                   (list (slow-computation) (slow-computation))))

; ========================================================================
(concat
 (list (slow-computation))
 (list (slow-computation) (slow-computation)))
; seq : "Elapsed time: 0.019 msecs"
; next : "Elapsed time: 0.028 msecs"
; rest : "Elapsed time: 0.02 msecs"
; first : "Elapsed time: 0.024 msecs"
; seq? : "Elapsed time: 0.012 msecs"
; list? : "Elapsed time: 0.02 msecs"
; empty? : "Elapsed time: 0.025 msecs"
; identity : "Elapsed time: 0.011 msecs"

nil
lazier.core> (benchmark* [identity empty? list? seq? first rest next seq]
           (concat (list (slow-computation)) (list (slow-computation) (slow-computation))))

; ========================================================================
(concat
 (list (slow-computation))
 (list (slow-computation) (slow-computation)))
; seq : "Elapsed time: 1500.205 msecs"
; next : "Elapsed time: 1500.356 msecs"
; rest : "Elapsed time: 1500.212 msecs"
; first : "Elapsed time: 1500.307 msecs"
; seq? : "Elapsed time: 1500.311 msecs"
; list? : "Elapsed time: 1500.281 msecs"
; empty? : "Elapsed time: 1500.171 msecs"
; identity : "Elapsed time: 1500.275 msecs"

got-it-right.clj

(benchmark [identity empty? list? seq? first rest next seq]
           (concat (lazy-seq (list (slow-computation))) 
                   (lazy-seq (list (slow-computation) 
                                   (slow-computation)))))

; ========================================================================
(concat
 (lazy-seq (list (slow-computation)))
 (lazy-seq (list (slow-computation) (slow-computation))))
; seq : "Elapsed time: 500.431 msecs"
; next : "Elapsed time: 1500.505 msecs"
; rest : "Elapsed time: 500.563 msecs"
; first : "Elapsed time: 500.381 msecs"
; seq? : "Elapsed time: 0.291 msecs"
; list? : "Elapsed time: 0.286 msecs"
; empty? : "Elapsed time: 500.462 msecs"
; identity : "Elapsed time: 0.301 msecs"

lazy-triple.clj

(benchmark [identity empty? list? seq? first rest next seq]
           (lazy-seq (cons (slow-computation)
                           (lazy-seq (cons (slow-computation)
                                           (lazy-seq (list (slow-computation))))))))


; ========================================================================
(lazy-seq
 (cons
  (slow-computation)
  (lazy-seq
   (cons (slow-computation) (lazy-seq (list (slow-computation)))))))
; seq : "Elapsed time: 500.609 msecs"
; next : "Elapsed time: 1000.94 msecs"
; rest : "Elapsed time: 500.536 msecs"
; first : "Elapsed time: 500.48 msecs"
; seq? : "Elapsed time: 0.177 msecs"
; list? : "Elapsed time: 0.169 msecs"
; empty? : "Elapsed time: 500.566 msecs"
; identity : "Elapsed time: 0.154 msecs"

list.clj

(benchmark [identity empty? list? seq? first rest next seq]
           (lazy-seq (list (slow-computation)
                           (slow-computation))))
; ========================================================================
(lazy-seq (list (slow-computation) (slow-computation)))
; seq : "Elapsed time: 1000.622 msecs"
; next : "Elapsed time: 1000.278 msecs"
; rest : "Elapsed time: 1000.276 msecs"
; first : "Elapsed time: 1000.279 msecs"
; seq? : "Elapsed time: 0.474 msecs"
; list? : "Elapsed time: 0.157 msecs"
; empty? : "Elapsed time: 1000.311 msecs"
; identity : "Elapsed time: 0.153 msecs"

more-benchmark.clj

(defmacro benchmark*
  [functions lst]
  (println ";" (str-join "" (repeat 72 \=)))
  (pprint `~lst)
  (letfn [(make-fragment [f] `(let [m# ~lst] (~f m#)))]
    `(do
       ~@(loop [functions functions timers []]
           (if (seq functions)
             (recur (rest functions)
                    (cons `(do
                             (print ";" (quote ~(first functions)) ": ")
                             (time ~(make-fragment (first functions)))
                             nil)
                          timers))
             timers))
       (println))))

(defmacro benchmark**
  [functions lst]
  (println ";" (str-join "" (repeat 72 \=)))
  (pprint `~lst)
  (letfn [(make-fragment [f] `(let [m# ~lst] (time (~f m#))))]
    `(do
       ~@(loop [functions functions timers []]
           (if (seq functions)
             (recur (rest functions)
                    (cons `(do
                             (print ";" (quote ~(first functions)) ": ")
                             ~(make-fragment (first functions))
                             nil)
                          timers))
             timers))
       (println))))