2 // Copyright Oliver Kowalke 2009.
3 // Distributed under the Boost Software License, Version 1.0.
4 // (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
11 #include <boost/chrono.hpp>
12 #include <boost/coroutine/all.hpp>
13 #include <boost/cstdint.hpp>
14 #include <boost/program_options.hpp>
16 #include "../bind_processor.hpp"
17 #include "../clock.hpp"
18 #include "../cycle.hpp"
20 typedef boost::coroutines::protected_stack_allocator stack_allocator;
21 typedef boost::coroutines::asymmetric_coroutine< void > coro_type;
23 boost::coroutines::flag_fpu_t preserve_fpu = boost::coroutines::fpu_not_preserved;
24 boost::coroutines::flag_unwind_t unwind_stack = boost::coroutines::stack_unwind;
25 boost::uint64_t jobs = 1000;
27 void fn( coro_type::push_type & c)
28 { while ( true) c(); }
30 duration_type measure_time( duration_type overhead)
32 stack_allocator stack_alloc;
34 time_point_type start( clock_type::now() );
35 for ( std::size_t i = 0; i < jobs; ++i) {
36 coro_type::pull_type c( fn,
37 boost::coroutines::attributes( unwind_stack, preserve_fpu), stack_alloc);
39 duration_type total = clock_type::now() - start;
40 total -= overhead_clock(); // overhead of measurement
41 total /= jobs; // loops
46 # ifdef BOOST_CONTEXT_CYCLE
47 cycle_type measure_cycles( cycle_type overhead)
49 stack_allocator stack_alloc;
51 cycle_type start( cycles() );
52 for ( std::size_t i = 0; i < jobs; ++i) {
53 coro_type::pull_type c( fn,
54 boost::coroutines::attributes( unwind_stack, preserve_fpu), stack_alloc);
56 cycle_type total = cycles() - start;
57 total -= overhead; // overhead of measurement
58 total /= jobs; // loops
64 int main( int argc, char * argv[])
68 bool preserve = false, unwind = true, bind = false;
69 boost::program_options::options_description desc("allowed options");
71 ("help", "help message")
72 ("bind,b", boost::program_options::value< bool >( & bind), "bind thread to CPU")
73 ("fpu,f", boost::program_options::value< bool >( & preserve), "preserve FPU registers")
74 ("unwind,u", boost::program_options::value< bool >( & unwind), "unwind coroutine-stack")
75 ("jobs,j", boost::program_options::value< boost::uint64_t >( & jobs), "jobs to run");
77 boost::program_options::variables_map vm;
78 boost::program_options::store(
79 boost::program_options::parse_command_line(
84 boost::program_options::notify( vm);
86 if ( vm.count("help") ) {
87 std::cout << desc << std::endl;
91 if ( preserve) preserve_fpu = boost::coroutines::fpu_preserved;
92 if ( ! unwind) unwind_stack = boost::coroutines::no_stack_unwind;
93 if ( bind) bind_to_processor( 0);
95 duration_type overhead_c = overhead_clock();
96 std::cout << "overhead " << overhead_c.count() << " nano seconds" << std::endl;
97 boost::uint64_t res = measure_time( overhead_c).count();
98 std::cout << "average of " << res << " nano seconds" << std::endl;
99 #ifdef BOOST_CONTEXT_CYCLE
100 cycle_type overhead_y = overhead_cycle();
101 std::cout << "overhead " << overhead_y << " cpu cycles" << std::endl;
102 res = measure_cycles( overhead_y);
103 std::cout << "average of " << res << " cpu cycles" << std::endl;
108 catch ( std::exception const& e)
109 { std::cerr << "exception: " << e.what() << std::endl; }
111 { std::cerr << "unhandled exception" << std::endl; }