ceph/src/boost/libs/coroutine/performance/symmetric/performance_create_protected.cpp

   1
   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)
   6
   7 #include <cstdlib>
   8 #include <iostream>
   9 #include <stdexcept>
  10
  11 #include <boost/chrono.hpp>
  12 #include <boost/coroutine/all.hpp>
  13 #include <boost/cstdint.hpp>
  14 #include <boost/program_options.hpp>
  15
  16 #include "../bind_processor.hpp"
  17 #include "../clock.hpp"
  18 #include "../cycle.hpp"
  19
  20 typedef boost::coroutines::protected_stack_allocator       stack_allocator;
  21 typedef boost::coroutines::symmetric_coroutine< void >     coro_type;
  22
  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;
  26
  27 void fn( coro_type::yield_type &) {}
  28
  29 duration_type measure_time( duration_type overhead)
  30 {
  31     stack_allocator stack_alloc;
  32     boost::coroutines::attributes attrs( unwind_stack, preserve_fpu);
  33
  34     time_point_type start( clock_type::now() );
  35     for ( std::size_t i = 0; i < jobs; ++i) {
  36         coro_type::call_type c( fn, attrs, stack_alloc);
  37     }
  38     duration_type total = clock_type::now() - start;
  39     total -= overhead; // overhead of measurement
  40     total /= jobs;  // loops
  41
  42     return total;
  43 }
  44
  45 # ifdef BOOST_CONTEXT_CYCLE
  46 cycle_type measure_cycles( cycle_type overhead)
  47 {
  48     stack_allocator stack_alloc;
  49
  50     cycle_type start( cycles() );
  51     for ( std::size_t i = 0; i < jobs; ++i) {
  52         coro_type::call_type c( fn,
  53             boost::coroutines::attributes( unwind_stack, preserve_fpu), stack_alloc);
  54     }
  55     cycle_type total = cycles() - start;
  56     total -= overhead; // overhead of measurement
  57     total /= jobs;  // loops
  58
  59     return total;
  60 }
  61 # endif
  62
  63 int main( int argc, char * argv[])
  64 {
  65     try
  66     {
  67         bool preserve = false, unwind = true, bind = false;
  68         boost::program_options::options_description desc("allowed options");
  69         desc.add_options()
  70             ("help", "help message")
  71             ("bind,b", boost::program_options::value< bool >( & bind), "bind thread to CPU")
  72             ("fpu,f", boost::program_options::value< bool >( & preserve), "preserve FPU registers")
  73             ("unwind,u", boost::program_options::value< bool >( & unwind), "unwind coroutine-stack")
  74             ("jobs,j", boost::program_options::value< boost::uint64_t >( & jobs), "jobs to run");
  75
  76         boost::program_options::variables_map vm;
  77         boost::program_options::store(
  78                 boost::program_options::parse_command_line(
  79                     argc,
  80                     argv,
  81                     desc),
  82                 vm);
  83         boost::program_options::notify( vm);
  84
  85         if ( vm.count("help") ) {
  86             std::cout << desc << std::endl;
  87             return EXIT_SUCCESS;
  88         }
  89
  90         if ( preserve) preserve_fpu = boost::coroutines::fpu_preserved;
  91         if ( ! unwind) unwind_stack = boost::coroutines::no_stack_unwind;
  92         if ( bind) bind_to_processor( 0);
  93
  94         duration_type overhead_c = overhead_clock();
  95         std::cout << "overhead " << overhead_c.count() << " nano seconds" << std::endl;
  96         boost::uint64_t res = measure_time( overhead_c).count();
  97         std::cout << "average of " << res << " nano seconds" << std::endl;
  98 #ifdef BOOST_CONTEXT_CYCLE
  99         cycle_type overhead_y = overhead_cycle();
 100         std::cout << "overhead " << overhead_y << " cpu cycles" << std::endl;
 101         res = measure_cycles( overhead_y);
 102         std::cout << "average of " << res << " cpu cycles" << std::endl;
 103 #endif
 104
 105         return EXIT_SUCCESS;
 106     }
 107     catch ( std::exception const& e)
 108     { std::cerr << "exception: " << e.what() << std::endl; }
 109     catch (...)
 110     { std::cerr << "unhandled exception" << std::endl; }
 111     return EXIT_FAILURE;
 112 }