C++中如何實(shí)現(xiàn)進(jìn)程池

在C++中可以使用多線程庫(kù)來(lái)實(shí)現(xiàn)進(jìn)程池，以下是一個(gè)簡(jiǎn)單的進(jìn)程池實(shí)現(xiàn)示例：

#include <iostream>
#include <vector>
#include <thread>
#include <mutex>
#include <condition_variable>
#include <queue>
#include <functional>

class ThreadPool {
public:
    ThreadPool(int numThreads) : stop(false) {
        for (int i = 0; i < numThreads; ++i) {
            workers.emplace_back([this] {
                while (true) {
                    std::function<void()> task;
                    {
                        std::unique_lock<std::mutex> lock(queueMutex);
                        condition.wait(lock, [this] { return stop || !tasks.empty(); });
                        if (stop && tasks.empty()) {
                            return;
                        }
                        task = tasks.front();
                        tasks.pop();
                    }
                    task();
                }
            });
        }
    }

    template<class F>
    void enqueue(F&& f) {
        {
            std::unique_lock<std::mutex> lock(queueMutex);
            tasks.emplace(std::forward<F>(f));
        }
        condition.notify_one();
    }

    ~ThreadPool() {
        {
            std::unique_lock<std::mutex> lock(queueMutex);
            stop = true;
        }
        condition.notify_all();
        for (std::thread &worker : workers) {
            worker.join();
        }
    }

private:
    std::vector<std::thread> workers;
    std::queue<std::function<void()>> tasks;
    std::mutex queueMutex;
    std::condition_variable condition;
    bool stop;
};

int main() {
    ThreadPool pool(4);

    for (int i = 0; i < 8; ++i) {
        pool.enqueue([i] {
            std::this_thread::sleep_for(std::chrono::seconds(1));
            std::cout << "Task " << i << " completed" << std::endl;
        });
    }

    return 0;
}

在上面的示例中，通過(guò)創(chuàng)建一個(gè)ThreadPool類來(lái)實(shí)現(xiàn)進(jìn)程池，其中包含了一個(gè)線程池的構(gòu)造函數(shù)、任務(wù)入隊(duì)函數(shù)enqueue和析構(gòu)函數(shù)?？梢酝ㄟ^(guò)調(diào)用enqueue函數(shù)向進(jìn)程池中添加任務(wù)，進(jìn)程池會(huì)自動(dòng)分配線程來(lái)執(zhí)行這些任務(wù)。