benchmark of dynamic variable access in clojure

dynamic_varialbe_access_benchmark.clj

(ns dynamic-varialbe-access-benchmark
  (:require [criterium.core :as criterium]))

(def ^:dynamic dynamic-x 1)

(def nondynamic-x 1)

(defn add-dynamic []
  (+ 1 dynamic-x))

(defn add-nondynamic []
  (+ 1 nondynamic-x))

(comment
  (criterium/with-progress-reporting (criterium/quick-bench (add-dynamic)))

;;   Warming up for JIT optimisations 5000000000 ...
;;   compilation occurred before 3832 iterations
;;   compilation occurred before 11494 iterations
;;   compilation occurred before 26818 iterations
;;   compilation occurred before 30649 iterations
;;   compilation occurred before 471214 iterations
;;   compilation occurred before 819835 iterations
;;   compilation occurred before 873469 iterations
;;   compilation occurred before 202583281 iterations
;;   compilation occurred before 243119092 iterations
;;   compilation occurred before 243122923 iterations
;; Estimating execution count ...
;; Sampling ...
;; Final GC...
;; Checking GC...
;; Finding outliers ...
;; Bootstrapping ...
;; Checking outlier significance
;; Evaluation count : 56853378 in 6 samples of 9475563 calls.
;;              Execution time mean : 9.046112 ns
;;     Execution time std-deviation : 0.029375 ns
;;    Execution time lower quantile : 9.028166 ns ( 2.5%)
;;    Execution time upper quantile : 9.095470 ns (97.5%)
;;                    Overhead used : 1.514405 ns

;; Found 1 outliers in 6 samples (16.6667 %)
;;      low-severe       1 (16.6667 %)
;;  Variance from outliers : 13.8889 % Variance is moderately inflated by outliers


  (criterium/with-progress-reporting (criterium/quick-bench (add-nondynamic)))

;; Warming up for JIT optimisations 5000000000 ...
;;   compilation occurred before 5457 iterations
;;   compilation occurred before 71921 iterations
;; Estimating execution count ...
;; Sampling ...
;; Final GC...
;; Checking GC...
;; Finding outliers ...
;; Bootstrapping ...
;; Checking outlier significance
;; Evaluation count : 58881858 in 6 samples of 9813643 calls.
;;              Execution time mean : 8.672314 ns
;;     Execution time std-deviation : 0.015605 ns
;;    Execution time lower quantile : 8.654678 ns ( 2.5%)
;;    Execution time upper quantile : 8.696120 ns (97.5%)
;;                    Overhead used : 1.514405 ns

;; Found 1 outliers in 6 samples (16.6667 %)
;;      low-severe       1 (16.6667 %)
;;  Variance from outliers : 13.8889 % Variance is moderately inflated by outliers

  )