Class Guide

example/sem.cpp:31–78

}

class alignas(128 /*std::hardware_destructive_interference_size*/) Guide {
    inline static co_context::mutex cout_mutex;
    inline static std::chrono::time_point<std::chrono::high_resolution_clock>
        started_at;
    unsigned delay{rnd()}, occupy{rnd()}, wait_on_sema{};

  public:
    static void start_time() {
        started_at = std::chrono::high_resolution_clock::now();
    }

    task<void> initial_delay() const { co_await timeout(delay * time_tick); }

    task<void> occupy_sema() {
        wait_on_sema = static_cast<unsigned>(
            std::chrono::duration_cast<std::chrono::milliseconds>(
                std::chrono::high_resolution_clock::now() - started_at
                - delay * time_tick
            )
                .count()
            / time_tick.count()
        );
        co_await timeout(occupy * time_tick);
    }

    task<void> visualize(unsigned id, unsigned x_scale = 2) const {
        auto cout_n = [=](auto str, unsigned n) {
            n *= x_scale;
            while (n-- > 0) {
                std::cout << str;
            }
        };
        auto guard = co_await cout_mutex.lock_guard();
        std::cout << "#" << std::setw(2) << id << " ";
        cout_n("░", delay);
        cout_n("▒", wait_on_sema);
        cout_n("█", occupy);
        std::cout << '\n';
    }

    static void show_info() {
        std::cout
            << "\nThreads: " << max_threads
            << ", Throughput: " << max_sema_threads
            << " │ Legend: initial delay ░░ │ wait state ▒▒ │ sema occupation ██ \n"
            << std::endl;
    }
};

std::array<Guide, max_threads> guides;