C++获取服务器性能指标-QPS 函数或者代码

获取服务器性能指标-QPS，可以使用以下代码：

#include <iostream>
#include <cstdio>
#include <chrono>
#include <thread>
#include <atomic>
#include <vector>
#include <string>
#include <algorithm>
#include <cstring>

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

void send_request(int sockfd) {
    std::string request("GET / HTTP/1.0\r\n\r\n");
    send(sockfd, request.c_str(), request.size(), 0);
}

void thread_func(const char* ip, int port, std::atomic<int>& count) {
    int sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd == -1) {
        std::cout << "create socket failed\n";
        return;
    }

    struct sockaddr_in serv_addr{};
    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = inet_addr(ip);
    serv_addr.sin_port = htons(port);

    if (connect(sockfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) == -1) {
        std::cout << "connect failed\n";
        return;
    }

    while (true) {
        send_request(sockfd);
        char buf[1024];
        int len = recv(sockfd, buf, sizeof(buf), 0);
        if (len == -1) {
            std::cout << "recv failed\n";
            break;
        } else if (len == 0) {
            std::cout << "server closed\n";
            break;
        }
        count++;
    }

    close(sockfd);
}

int main() {
    std::vector<std::thread> threads;
    std::atomic<int> count{0};
    const char* ip = "127.0.0.1";
    int port = 80;
    int thread_num = 10;
    int seconds = 10;

    for (int i = 0; i < thread_num; ++i) {
        threads.emplace_back(thread_func, ip, port, std::ref(count));
    }

    std::this_thread::sleep_for(std::chrono::seconds(seconds));

    for (auto& t : threads) {
        t.join();
    }

    std::cout << "QPS: " << count / (double)seconds << '\n';

    return 0;
}

该程序会创建多个线程，每个线程不断向服务器发送请求，并计算总共发送的请求数量，最后根据时间计算出 QPS 值。

需要注意的是，该程序只适用于 HTTP 协议的服务器，若要测试其他协议的服务器，需要修改发送请求的内容和解析响应的方式。同时，该程序也需要在 Linux 环境下编译运行。