在Windows平台下实现高并发网站，主要有以下几种技术方案：

1.IOCP (I/O Completion Ports) - Windows最高性能方案

核心特性

cpp

#include <winsock2.h>
#include <mswsock.h>

class IOCPServer {
private:
    HANDLE iocp_port;
    std::vector<std::thread> workers;
    
public:
    void start() {
        // 创建IOCP句柄
        iocp_port = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0);
        
        // 创建工作线程
        for(int i = 0; i < std::thread::hardware_concurrency(); ++i) {
            workers.emplace_back([this] { worker_thread(); });
        }
        
        // 接受连接并关联到IOCP
        SOCKET listen_socket = create_listen_socket();
        while(true) {
            SOCKET client_socket = accept(listen_socket, NULL, NULL);
            CreateIoCompletionPort((HANDLE)client_socket, iocp_port, (ULONG_PTR)client_socket, 0);
            
            // 投递异步接收操作
            post_async_recv(client_socket);
        }
    }
    
private:
    void worker_thread() {
        while(true) {
            DWORD bytes_transferred;
            ULONG_PTR completion_key;
            OVERLAPPED* overlapped;
            
            BOOL result = GetQueuedCompletionStatus(
                iocp_port, &bytes_transferred, &completion_key, &overlapped, INFINITE);
            
            if(result) {
                // 处理完成的I/O操作
                process_completion(completion_key, bytes_transferred, overlapped);
            }
        }
    }
};

优势

• 真正的异步I/O，内核级别的高效调度
• 可处理数万到数十万并发连接
• CPU利用率高，上下文切换少

2.HTTP.sys 内核模式驱动

使用HTTP Server API

cpp

#include <http.h>
#pragma comment(lib, "httpapi.lib")

class HttpSysServer {
public:
    void start() {
        HTTPAPI_VERSION version = HTTPAPI_VERSION_2;
        HttpInitialize(version, HTTP_INITIALIZE_SERVER, NULL);
        
        // 创建URL组和请求队列
        HTTP_SERVER_SESSION_ID server_session;
        HttpCreateServerSession(version, &server_session, 0);
        
        HTTP_URL_GROUP_ID url_group;
        HttpCreateUrlGroup(server_session, &url_group, 0);
        
        // 添加URL
        HttpAddUrlToUrlGroup(url_group, L"http://localhost:80/", 0, 0);
        
        // 创建请求队列
        HANDLE request_queue;
        HttpCreateRequestQueue(version, L"MyApp", NULL, 0, &request_queue);
        
        // 开始处理请求
        process_requests(request_queue);
    }
    
private:
    void process_requests(HANDLE request_queue) {
        while(true) {
            HTTP_REQUEST_ID request_id;
            DWORD bytes_read;
            PHTTP_REQUEST request = get_http_request(request_queue, &request_id, &bytes_read);
            
            // 处理请求并发送响应
            HTTP_RESPONSE response = {0};
            response.StatusCode = 200;
            HttpSendHttpResponse(request_queue, request_id, 0, &response, NULL, NULL, NULL, NULL, NULL, NULL);
        }
    }
};

优势

• 内核级别处理，性能极高
• 内置连接管理、缓存、SSL卸载
• IIS使用的一样技术

3.ASP.NETCore - 现代跨平台方案

Startup配置

csharp

public class Program
{
    public static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }

    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureWebHostDefaults(webBuilder =>
            {
                webBuilder
                    .UseKestrel(options =>
                    {
                        // 配置Kestrel服务器
                        options.Listen(IPAddress.Any, 5000, listenOptions =>
                        {
                            listenOptions.Protocols = HttpProtocols.Http1AndHttp2;
                        });
                    })
                    .UseStartup<Startup>();
            });
}

public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers();
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseRouting();
        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });
    }
}

Kestrel服务器优化配置

csharp

// Program.cs
webBuilder.UseKestrel(options =>
{
    options.Limits.MaxConcurrentConnections = 10000;
    options.Limits.MaxConcurrentUpgradedConnections = 10000;
    options.Limits.MaxRequestBodySize = 28_000_000; // 28MB
    options.Limits.KeepAliveTimeout = TimeSpan.FromMinutes(2);
    options.Limits.RequestHeadersTimeout = TimeSpan.FromMinutes(1);
});

4.第三方高性能框架

1.Boost.Asio (C++)

cpp

#include <boost/asio.hpp>
#include <boost/asio/use_awaitable.hpp>
#include <boost/asio/co_spawn.hpp>

using boost::asio::ip::tcp;
namespace this_coro = boost::asio::this_coro;

boost::asio::awaitable<void> handle_session(tcp::socket socket)
{
    try {
        std::vector<char> data(1024);
        for (;;) {
            std::size_t n = co_await socket.async_read_some(
                boost::asio::buffer(data), boost::asio::use_awaitable);
            
            // 处理请求
            co_await socket.async_write_some(
                boost::asio::buffer("HTTP/1.1 200 OK

Hello World"), 
                boost::asio::use_awaitable);
        }
    }
    catch (std::exception& e) {
        // 处理异常
    }
}

boost::asio::awaitable<void> listener()
{
    auto executor = co_await this_coro::executor;
    tcp::acceptor acceptor(executor, {tcp::v4(), 8080});
    
    for (;;) {
        tcp::socket socket = co_await acceptor.async_accept(boost::asio::use_awaitable);
        boost::asio::co_spawn(executor, handle_session(std::move(socket)), boost::asio::detached);
    }
}

2.Drogon (C++)

cpp

#include <drogon/drogon.h>

int main()
{
    drogon::app()
        .setLogLevel(trantor::Logger::kWarn)
        .addListener("0.0.0.0", 8080)
        .setThreadNum(16)  // 设置IO线程数
        .setMaxConnectionNum(10000)  // 最大连接数
        .run();
    
    return 0;
}

5.Windows特有优化技术

1.设置线程亲和性

cpp

void set_thread_affinity() {
    DWORD_PTR affinity_mask = 1;  // 第一个CPU核心
    SetThreadAffinityMask(GetCurrentThread(), affinity_mask);
    
    // 或者使用自动负载均衡
    SYSTEM_INFO sys_info;
    GetSystemInfo(&sys_info);
    SetProcessAffinityMask(GetCurrentProcess(), 
                          (1 << sys_info.dwNumberOfProcessors) - 1);
}

2.内存池优化

cpp

#include <memoryapi.h>

class WindowsMemoryPool {
private:
    HANDLE heap;
    
public:
    WindowsMemoryPool() {
        heap = HeapCreate(0, 0, 0);  // 创建私有堆
    }
    
    void* allocate(size_t size) {
        return HeapAlloc(heap, 0, size);
    }
    
    void deallocate(void* ptr) {
        HeapFree(heap, 0, ptr);
    }
};

3.注册表性能优化

batch

# 调整TCP参数
netsh int tcp set global autotuninglevel=normal
netsh int tcp set global rss=enabled
netsh int tcp set global chimney=automatic

6.架构层面的优化

1.负载均衡 + 多实例

text

客户端 → 负载均衡器 (Nginx/HAProxy) 
        → 多个应用服务器实例
        → 数据库/缓存集群

2.缓存策略

• Redis集群缓存
• 内存缓存 (MemoryCache)
• CDN静态资源缓存

3.数据库优化

• SQL Server连接池
• 读写分离
• 数据库分片

性能对比

技术方案	并发能力	开发复杂度	适用场景
IOCP
	10万+	高	游戏服务器、实时通信
HTTP.sys	5万+	中	企业内部系统、API网关
ASP.NET Core	2万+	低	Web应用、微服务
Boost.Asio	5万+	中高	跨平台高性能应用

推荐选择

1. 企业级应用：ASP.NET Core + Kestrel
2. 极致性能需求：IOCP + C++
3. 现有.NET技术栈：HTTP.sys
4. 跨平台需求：Boost.Asio 或 Drogon

根据具体业务需求、团队技术栈和性能要求选择合适的方案。对于大多数Web应用场景，ASP.NET Core已经能够提供足够好的性能，且开发效率最高。