ceph/src/boost/libs/coroutine2/performance/performance_create_protected.cpp

   1
   2 //          Copyright Oliver Kowalke 2014.
   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/coroutine2/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::coroutines2::protected_fixedsize_stack   stack_allocator;
  21 typedef boost::coroutines2::coroutine< void >           coro_type;
  22
  23 boost::uint64_t jobs = 1000;
  24
  25 void fn( coro_type::pull_type & c)
  26 { while ( true) c(); }
  27
  28 duration_type measure_time( duration_type overhead)
  29 {
  30     stack_allocator stack_alloc;
  31
  32     time_point_type start( clock_type::now() );
  33     for ( std::size_t i = 0; i < jobs; ++i) {
  34         coro_type::push_type c( stack_alloc, fn);
  35     }
  36     duration_type total = clock_type::now() - start;
  37     total -= overhead_clock(); // overhead of measurement
  38     total /= jobs;  // loops
  39
  40     return total;
  41 }
  42
  43 # ifdef BOOST_CONTEXT_CYCLE
  44 cycle_type measure_cycles( cycle_type overhead)
  45 {
  46     stack_allocator stack_alloc;
  47
  48     cycle_type start( cycles() );
  49     for ( std::size_t i = 0; i < jobs; ++i) {
  50         coro_type::push_type c( stack_alloc, fn);
  51     }
  52     cycle_type total = cycles() - start;
  53     total -= overhead; // overhead of measurement
  54     total /= jobs;  // loops
  55
  56     return total;
  57 }
  58 # endif
  59
  60 int main( int argc, char * argv[])
  61 {
  62     try
  63     {
  64         bool bind = false;
  65         boost::program_options::options_description desc("allowed options");
  66         desc.add_options()
  67             ("help", "help message")
  68             ("bind,b", boost::program_options::value< bool >( & bind), "bind thread to CPU")
  69             ("jobs,j", boost::program_options::value< boost::uint64_t >( & jobs), "jobs to run");
  70
  71         boost::program_options::variables_map vm;
  72         boost::program_options::store(
  73                 boost::program_options::parse_command_line(
  74                     argc,
  75                     argv,
  76                     desc),
  77                 vm);
  78         boost::program_options::notify( vm);
  79
  80         if ( vm.count("help") ) {
  81             std::cout << desc << std::endl;
  82             return EXIT_SUCCESS;
  83         }
  84
  85         if ( bind) bind_to_processor( 0);
  86
  87         duration_type overhead_c = overhead_clock();
  88         boost::uint64_t res = measure_time( overhead_c).count();
  89         std::cout << "average of " << res << " nano seconds" << std::endl;
  90 #ifdef BOOST_CONTEXT_CYCLE
  91         cycle_type overhead_y = overhead_cycle();
  92         res = measure_cycles( overhead_y);
  93         std::cout << "average of " << res << " cpu cycles" << std::endl;
  94 #endif
  95
  96         return EXIT_SUCCESS;
  97     }
  98     catch ( std::exception const& e)
  99     { std::cerr << "exception: " << e.what() << std::endl; }
 100     catch (...)
 101     { std::cerr << "unhandled exception" << std::endl; }
 102     return EXIT_FAILURE;
 103 }