Question

我试图弄清楚为什么qperf报告延迟（单向）x，而REQ / REP（往返）报告类似4x的情况。我需要做任何特定的套接字调整吗？因为如果我只是打开套接字，则设置TCP_NODELAY（默认情况下在ZMQ中设置）会导致延迟（对于1k缓冲区）非常接近qperf报告的数字。但是ZMQ落后这些数字大约4-5倍
ZMQ服务器

zmq::context_t context;
zmq::socket_t socket(context, ZMQ_REP);

socket.bind("tcp://*:5555");

while (true) {
    zmq::message_t request;

    //  Wait for next request from client
    socket.recv(&request);

    //  Send reply back to client
    zmq::message_t reply(5);
    memcpy(reply.data(), "World", 5);
    socket.send(reply);
}

ZMQ客户端

zmq::context_t context;
zmq::socket_t socket(context, ZMQ_REQ);

std::cout << "Connecting to hello world server…" << std::endl;
socket.connect("tcp://my.host:5555");

const size_t cycles = 100'000;
double throughput = 0;

zmq::message_t reply;

auto start = std::chrono::high_resolution_clock::now();
vector<uint8_t> buff(MessageSize, 0);
for (auto i = 0ul; i < cycles; ++i) {
    zmq::message_t request(MessageSize);
    memcpy(request.data(), buff.data(), MessageSize);
    throughput += request.size();
    socket.send(request);
    //  Get the reply.
    socket.recv(&reply);
}
auto end = std::chrono::high_resolution_clock::now();
auto us = std::chrono::duration_cast<std::chrono::microseconds>(end - start).count();
std::cout << "Latency: " << us / cycles << "us." << std::endl;
std::cout << "Througput: " << std::fixed << throughput / us * 1'000'000 / 1024 / 1024 << "MiB/s." << std::endl;

本质上，这两个都是ZMQ示例http://zguide.zeromq.org/cpp:hwclient 由vcpkg提供的某些背景，Linux，Ubuntu，GCC 7.3，静态库是在本地构建的，好像它们是从github上获取母版一样。

与qperf报告的延迟相比，zmq cpp性能

0 个答案: