ceph/src/boost/libs/fiber/performance/fiber/skynet_shared_detach.cpp

   1
   2 //          Copyright Oliver Kowalke 2015.
   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 // based on https://github.com/atemerev/skynet from Alexander Temerev
   8
   9 #include <algorithm>
  10 #include <cassert>
  11 #include <chrono>
  12 #include <cmath>
  13 #include <condition_variable>
  14 #include <cstddef>
  15 #include <cstdint>
  16 #include <cstdlib>
  17 #include <deque>
  18 #include <iostream>
  19 #include <memory>
  20 #include <mutex>
  21 #include <numeric>
  22 #include <vector>
  23
  24 #include <boost/fiber/all.hpp>
  25 #include <boost/predef.h>
  26
  27 #include "barrier.hpp"
  28
  29 using allocator_type = boost::fibers::fixedsize_stack;
  30 using channel_type = boost::fibers::buffered_channel< std::uint64_t >;
  31 using clock_type = std::chrono::steady_clock;
  32 using duration_type = clock_type::duration;
  33 using lock_type = std::unique_lock< std::mutex >;
  34 using time_point_type = clock_type::time_point;
  35
  36 static bool done = false;
  37 static std::mutex mtx{};
  38 static boost::fibers::condition_variable_any cnd{};
  39
  40 // microbenchmark
  41 void skynet( allocator_type & salloc, channel_type & c, std::size_t num, std::size_t size, std::size_t div) {
  42     if ( 1 == size) {
  43         c.push( num);
  44     } else {
  45         channel_type rc{ 16 };
  46         for ( std::size_t i = 0; i < div; ++i) {
  47             auto sub_num = num + i * size / div;
  48             boost::fibers::fiber{ boost::fibers::launch::dispatch,
  49                               std::allocator_arg, salloc,
  50                               skynet,
  51                               std::ref( salloc), std::ref( rc), sub_num, size / div, div }.detach();
  52         }
  53         std::uint64_t sum{ 0 };
  54         for ( std::size_t i = 0; i < div; ++i) {
  55             sum += rc.value_pop();
  56         }
  57         c.push( sum);
  58     }
  59 }
  60
  61 void thread( unsigned int idx, barrier * b) {
  62     boost::fibers::numa::pin_thread( idx);
  63     boost::fibers::use_scheduling_algorithm< boost::fibers::algo::shared_work >();
  64     b->wait();
  65     lock_type lk( mtx);
  66     cnd.wait( lk, [](){ return done; });
  67     BOOST_ASSERT( done);
  68 }
  69
  70 int main() {
  71     try {
  72         boost::fibers::use_scheduling_algorithm< boost::fibers::algo::shared_work >();
  73         unsigned int n = std::thread::hardware_concurrency();
  74         barrier b( n);
  75         boost::fibers::numa::pin_thread( n - 1);
  76         std::size_t size{ 1000000 };
  77         std::size_t div{ 10 };
  78         std::vector< std::thread > threads;
  79         for ( unsigned int i = 1; i < n; ++i) {
  80             threads.emplace_back( thread, i - 1, & b);
  81         };
  82         // Windows 10 and FreeBSD require a fiber stack of 8kb
  83         // otherwise the stack gets exhausted
  84         // stack requirements must be checked for other OS too
  85 #if BOOST_OS_WINDOWS || BOOST_OS_BSD
  86         allocator_type salloc{ 2*allocator_type::traits_type::page_size() };
  87 #else
  88         allocator_type salloc{ allocator_type::traits_type::page_size() };
  89 #endif
  90         std::uint64_t result{ 0 };
  91         channel_type rc{ 2 };
  92         b.wait();
  93         time_point_type start{ clock_type::now() };
  94         skynet( salloc, rc, 0, size, div);
  95         result = rc.value_pop();
  96         if ( 499999500000 != result) {
  97             throw std::runtime_error("invalid result");
  98         }
  99         auto duration = clock_type::now() - start;
 100         lock_type lk( mtx);
 101         done = true;
 102         lk.unlock();
 103         cnd.notify_all();
 104         for ( std::thread & t : threads) {
 105             t.join();
 106         }
 107         std::cout << "duration: " << duration.count() / 1000000 << " ms" << std::endl;
 108         return EXIT_SUCCESS;
 109     } catch ( std::exception const& e) {
 110         std::cerr << "exception: " << e.what() << std::endl;
 111     } catch (...) {
 112         std::cerr << "unhandled exception" << std::endl;
 113     }
 114         return EXIT_FAILURE;
 115 }