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/* 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;
}
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