我决定找出Protobuf、Flatbuffers和Cap 'n proto中哪一个对我的应用程序来说是最好/最快的序列化。在我的例子中，我通过网络发送某种字节/字符数组（这是我序列化为那种格式的原因）。所以我对这三个都做了简单的实现，我对字符串、浮点数和整型进行了序列化和去零化。这产生了意想不到的结果：Protobuf是最快的。我认为它们是出乎意料的，因为cap 'n proto和flatbuffes都“声称”是更快的选项。在我接受这个说法之前，我想看看我是否故意在代码中作弊。如果我没有作弊，我想知道为什么protobuf更快（确切的原因可能是不可能的）。消息是否可以简化cap' n proto和faltbuffes，以真正使它们发光？

我的计时：

平面缓冲区花费的时间：14162微秒
所用时间capnp：60259微秒
protobuf花费的时间：12131微秒
(time相对比较可能是相关的。）

• 更新：以上数字不代表正确的用法，至少不代表capnp --见答案和评论。*
  平面缓冲区代码：

int main (int argc, char *argv[]){
    std::string s = "string";
    float f = 3.14;
    int i = 1337;

    std::string s_r;
    float f_r;
    int i_r;
    flatbuffers::FlatBufferBuilder message_sender;
    
    int steps = 10000;
    auto start = high_resolution_clock::now(); 
    for (int j = 0; j < steps; j++){
        auto autostring =  message_sender.CreateString(s);
        auto encoded_message = CreateTestmessage(message_sender, autostring, f, i);
        message_sender.Finish(encoded_message);
        uint8_t *buf = message_sender.GetBufferPointer();
        int size = message_sender.GetSize();
        message_sender.Clear();
        //Send stuffs
        //Receive stuffs
        auto recieved_message = GetTestmessage(buf);

        s_r = recieved_message->string_()->str();
        f_r = recieved_message->float_();
        i_r = recieved_message->int_(); 
    }
    auto stop = high_resolution_clock::now(); 
    auto duration = duration_cast<microseconds>(stop - start); 
    cout << "Time taken flatbuffer: " << duration.count() << " microseconds" << endl;
    return 0;
}

cap 'n原型代码：

int main (int argc, char *argv[]){
    char s[] = "string";
    float f = 3.14;
    int i = 1337;

    const char * s_r;
    float f_r;
    int i_r;
    ::capnp::MallocMessageBuilder message_builder;
    Testmessage::Builder message = message_builder.initRoot<Testmessage>();

    int steps = 10000;
    auto start = high_resolution_clock::now(); 
    for (int j = 0; j < steps; j++){  
        //Encodeing
        message.setString(s);
        message.setFloat(f);
        message.setInt(i);

        kj::Array<capnp::word> encoded_array = capnp::messageToFlatArray(message_builder);
        kj::ArrayPtr<char> encoded_array_ptr = encoded_array.asChars();
        char * encoded_char_array = encoded_array_ptr.begin();
        size_t size = encoded_array_ptr.size();
        //Send stuffs
        //Receive stuffs

        //Decodeing
        kj::ArrayPtr<capnp::word> received_array = kj::ArrayPtr<capnp::word>(reinterpret_cast<capnp::word*>(encoded_char_array), size/sizeof(capnp::word));
        ::capnp::FlatArrayMessageReader message_receiver_builder(received_array);
        Testmessage::Reader message_receiver = message_receiver_builder.getRoot<Testmessage>();
        s_r = message_receiver.getString().cStr();
        f_r = message_receiver.getFloat();
        i_r = message_receiver.getInt();
    }
    auto stop = high_resolution_clock::now(); 
    auto duration = duration_cast<microseconds>(stop - start); 
    cout << "Time taken capnp: " << duration.count() << " microseconds" << endl;
    return 0;

}

协议缓冲区代码：

int main (int argc, char *argv[]){
    std::string s = "string";
    float f = 3.14;
    int i = 1337;

    std::string s_r;
    float f_r;
    int i_r;
    Testmessage message_sender;
    Testmessage message_receiver;
    int steps = 10000;
    auto start = high_resolution_clock::now(); 
    for (int j = 0; j < steps; j++){
        message_sender.set_string(s);
        message_sender.set_float_m(f);
        message_sender.set_int_m(i);
        int len = message_sender.ByteSize();
        char encoded_message[len];
        message_sender.SerializeToArray(encoded_message, len);
        message_sender.Clear();

        //Send stuffs
        //Receive stuffs
        message_receiver.ParseFromArray(encoded_message, len);
        s_r = message_receiver.string();
        f_r = message_receiver.float_m();
        i_r = message_receiver.int_m();
        message_receiver.Clear();
       
    }
    auto stop = high_resolution_clock::now(); 
    auto duration = duration_cast<microseconds>(stop - start); 
    cout << "Time taken protobuf: " << duration.count() << " microseconds" << endl;
    return 0;
}

不包括消息定义文件，因为它们很简单，很可能与此无关。