/* boost nondet_random_speed.cpp performance test * * Copyright Jens Maurer 2000 * Permission to use, copy, modify, sell, and distribute this software * is hereby granted without fee provided that the above copyright notice * appears in all copies and that both that copyright notice and this * permission notice appear in supporting documentation, * * Jens Maurer makes no representations about the suitability of this * software for any purpose. It is provided "as is" without express or * implied warranty. * * $Id: nondet_random_speed.cpp,v 1.4 2001/11/19 22:13:04 jmaurer Exp $ * */ #include <iostream> #include <string> #include <boost/timer.hpp> #include <boost/nondet_random.hpp> // set to your CPU frequency in MHz static const double cpu_frequency = 200 * 1e6; static void show_elapsed(double end, int iter, const std::string & name) { double usec = end/iter*1e6; double cycles = usec * cpu_frequency/1e6; std::cout << name << ": " << usec*1e3 << " nsec/loop = " << cycles << " CPU cycles" << std::endl; } template<class Result, class RNG> static void timing(RNG & rng, int iter, const std::string& name) { volatile Result tmp; // make sure we're not optimizing too much boost::timer t; for(int i = 0; i < iter; i++) tmp = rng(); show_elapsed(t.elapsed(), iter, name); } template<class RNG> void run(int iter, const std::string & name) { RNG rng; timing<long>(rng, iter, name); } int main(int argc, char*argv[]) { if(argc != 2) { std::cerr << "usage: " << argv[0] << " iterations" << std::endl; return 1; } int iter = std::atoi(argv[1]); #ifdef __linux__ boost::random_device dev; timing<unsigned int>(dev, iter, "random_device"); #else #error The non-deterministic random device is currently available on Linux only. #endif return 0; }