rnd-speed-test.lisp

#!/usr/bin/sbcl --script

(declaim (inline rnd))
(defun rnd (a)
  (declare (double-float a))
  (the double-float (random (the double-float a))))

(declaim (inline sb-kernel::%random-fixnum))
(sb-ext:unlock-package 'sb-kernel)


(let ((n 300000000))

  (time (loop repeat n do (rnd 10d0))) ; 3.226 seconds
  (time (loop repeat n do (sb-kernel::%random-double-float 10d0 *random-state*))) ; 3.290 seconds
  )