bench.clj

(ns json-bench.core
  (:require [cheshire.core :as cheshire])
  (:require [clojure.data.json :as json])
  (:require [clj-json.core :as clj-json]))

(defn nano-time []
  (System/nanoTime))

(defn timed [task]
  (let [t-start (nano-time)
        res     (task)
        t-end   (nano-time)]
    (double (/ (- t-end t-start) 1000000000))))

(def record
  {:keyword :foo
   :string "Lorem ipsum dolor sit amet, consectetur adipiscing elit."
   :integer 3
   :long 52001110638799097
   :double 1.23
   :boolean true
   :nil nil
   :map {"hi" 9 "low" 0}
   :vector ["a" "b" "c"]
   :list '(1 2 3)})

(def roundtrips 100000)

(defn bench [name f]
  (print name "  ")
  (flush)
  (printf "%.2f\n" (timed #(dotimes [_ roundtrips] (f record))))
  (flush))

(defn -main [& args]
  (println "Clojure version: "
           (str (:major       *clojure-version*) "."
                (:minor       *clojure-version*) "."
                (:incremental *clojure-version*)))
  (println "Num roundtrips:  "  roundtrips)
  (println)
  (dotimes [i 2]
    (println "Trail: " (inc i))
    (bench "cheshire                            "
           #(cheshire/parse-string (cheshire/generate-string %)))
    (bench "clojure.data.json                   "
           #(json/read-json (json/json-str %)))
    (bench "clj-json                            "
           #(clj-json/parse-string (clj-json/generate-string %)))
    (bench "reader/printer (*print-dup* false)  "
           #(binding [*print-dup* false] (read-string (pr-str %))))
    (bench "reader/printer (*print-dup* true)   "
           #(binding [*print-dup* true] (read-string (pr-str %))))
    (println)))

results.txt

Clojure version:  1.3.0
Num roundtrips:   100000

Trail:  1
cheshire                               3.21
clojure.data.json                      6.93
clj-json                               2.72
reader/printer (*print-dup* false)     11.34
reader/printer (*print-dup* true)      14.28

Trail:  2
cheshire                               2.45
clojure.data.json                      6.52
clj-json                               1.99
reader/printer (*print-dup* false)     9.10
reader/printer (*print-dup* true)      13.09