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// Copyright 2011 Vicente J. Botet Escriba
// Copyright (c) Microsoft Corporation 2014
// Distributed under the Boost Software License, Version 1.0.
// See http://www.boost.org/LICENSE_1_0.txt
#include "../example/timer.hpp"
#include <boost/chrono/chrono.hpp>
#include <boost/chrono/chrono_io.hpp>
#include <boost/chrono/process_cpu_clocks.hpp>
#include <vector>
#include <iostream>
//#define BOOST_CHRONO_HAS_TIMES_AND_CLOCK
#ifdef BOOST_CHRONO_HAS_TIMES_AND_CLOCK
#include <sys/time.h> //for gettimeofday and timeval
#include <sys/times.h> //for times
#include <unistd.h>
#endif
static const std::size_t size = 1000000;
typedef boost_ex::chrono::timer<boost::chrono::high_resolution_clock> Stopwatch;
template <typename Clock>
void perf_constant(std::vector<typename Clock::time_point>& vec)
{
for (int i=size-1; i>=0; --i)
{
vec[i]=typename Clock::time_point();
}
}
template <typename Clock>
void perf(std::vector<typename Clock::time_point>& vec)
{
for (int i=size-1; i>=0; --i)
{
vec[i]=Clock::now();
}
}
template <typename Clock>
void test()
{
std::vector<typename Clock::time_point> vec(size);
Stopwatch sw1;
perf_constant<Clock>(vec);
Stopwatch::duration t1 = sw1.elapsed();
Stopwatch sw2;
perf<Clock>(vec);
Stopwatch::duration t2 = sw2.elapsed();
std::cout <<" "<< (t2-t1) << std::endl;
//std::cout <<" "<< ((t2-t1)/size) << std::endl;
std::size_t cnt=0;
for (int i=size-1; i>0; --i)
{
if (vec[i]!=vec[i-1]) ++cnt;
}
std::cout <<"changes: "<< cnt << std::endl;
}
#ifdef BOOST_CHRONO_HAS_TIMES_AND_CLOCK
void perf2(std::vector<clock_t>& vec)
{
Stopwatch sw;
for (int i=size-1; i>=0; --i)
{
tms tm;
vec[i]=::times(&tm);
}
std::cout << sw.elapsed() << std::endl;
}
void perf3(std::vector<clock_t>& vec)
{
Stopwatch sw;
for (int i=size-1; i>=0; --i)
{
vec[i]=::clock();
}
std::cout << sw.elapsed() << std::endl;
}
void test2()
{
std::vector<clock_t> vec(size);
perf2(vec);
std::size_t cnt=0;
for (int i=10; i>0; --i)
{
if (vec[i]!=vec[i-1]) ++cnt;
std::cout << vec[i] << " " ;
}
std::cout<< std::endl;
std::cout <<"changes: "<< cnt << std::endl;
}
void test3()
{
std::vector<clock_t> vec(size);
perf3(vec);
std::size_t cnt=0;
for (int i=10; i>0; --i)
{
if (vec[i]!=vec[i-1]) ++cnt;
std::cout << vec[i] << " " ;
}
std::cout<< std::endl;
std::cout <<"changes: "<< cnt << std::endl;
}
#endif
int main() {
std::cout << "system_clock ";
test<boost::chrono::system_clock>();
#ifdef BOOST_CHRONO_HAS_CLOCK_STEADY
std::cout << "steady_clock " ;
test<boost::chrono::steady_clock>();
#endif
std::cout << "high_resolution_clock " ;
test<boost::chrono::high_resolution_clock>();
#if defined(BOOST_CHRONO_HAS_PROCESS_CLOCKS)
std::cout << "process_real_cpu_clock ";
test<boost::chrono::process_real_cpu_clock>();
#if ! BOOST_OS_WINDOWS || BOOST_PLAT_WINDOWS_DESKTOP
std::cout << "process_user_cpu_clock ";
test<boost::chrono::process_user_cpu_clock>();
std::cout << "process_system_cpu_clock " ;
test<boost::chrono::process_system_cpu_clock>();
std::cout << "process_cpu_clock " ;
test<boost::chrono::process_cpu_clock>();
#endif
#endif
std::cout << "system_clock ";
test<boost::chrono::system_clock>();
#if 0
std::cout << "times ";
test2();
std::cout << "clock ";
test3();
#endif
return 0;
}
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