// 它完成从工作线程发出http请求的工作
static void ThreadProc(object stateInfo)
{
ThreadStateInfo tsInfo = stateInfo as ThreadStateInfo;
try
{
HttpWebRequest aReq = WebRequest.Create(tsInfo.StrUrl) as HttpWebRequest;
var servicePoint = aReq.ServicePoint.ConnectionLimit;
aReq.Timeout = 1000 * 60;
Console.WriteLine($"Begin Request {tsInfo.IReqNumber} {DateTime.Now:yyyy-MM-dd HH:mm:ss:fff}");
var sw = new Stopwatch();
sw.Start();
HttpWebResponse aResp = aReq.GetResponse() as HttpWebResponse;
sw.Stop();
var thread = Thread.CurrentThread;
Console.WriteLine($"Response {tsInfo.IReqNumber} Time {sw.ElapsedMilliseconds} {DateTime.Now:yyyy-MM-dd HH:mm:ss:fff}");
aResp.Close(); // 如果不执行此关闭操作，则肯定会超时,套接字将不会被释放。
Thread.Sleep(500); //模拟服务器处理请求的半秒延迟
Console.WriteLine("End Request {0}", tsInfo.IReqNumber);
}
catch (WebException theEx)
{
Console.WriteLine("Exception for Request {0}: {1}", tsInfo.IReqNumber, theEx.Message);
}
//通知主线程这个请求已经完成
tsInfo.EvtReset.Set();
}
/// <summary>
/// 测试HttpRequest在高并发情况下的响应时间
/// </summary>
public void HttpRequestConcurrentTest()
{
//可以同时发出请求的工作线程的数量(不要超过64)
int numberRequests = 64;
//用于使主线程保持活动状态，直到所有请求完成
var manualEvents = new ManualResetEvent[numberRequests];
//访问的网址
var httpSite = "http://www.baidu.com";
//设置默认HTTP并发连接数
ServicePointManager.DefaultConnectionLimit = 2;
//ServicePointManager.MaxServicePointIdleTime = 7000;
//获取线程池的当前设置
ThreadPool.GetMinThreads(out var minWorker, out var minIoc);
var sw = new Stopwatch();
sw.Start();
//如果没有设置线程池，就会有足够的延迟导致Web请求超时
ThreadPool.SetMinThreads(64, minIoc);
#region Parallel并行并限制并发数为4
var options = new ParallelOptions
{
MaxDegreeOfParallelism = 32, //设置最大并行数
};
Parallel.For(0, 64, options, (i, pls) =>
{
//创建一个类来传递信息给线程
ThreadStateInfo theInfo = new ThreadStateInfo();
manualEvents[i] = new ManualResetEvent(false); //线程完成的事件
theInfo.EvtReset = manualEvents[i];
theInfo.IReqNumber = i; //跟踪这是什么请求
theInfo.StrUrl = httpSite; // 要打开的URL
ThreadProc(theInfo);
});
#endregion
/*for (int i = 0; i < numberRequests; i++)
* {
* //创建一个类来传递信息给线程
* ThreadStateInfo theInfo = new ThreadStateInfo();
*
* manualEvents[i] = new ManualResetEvent(false); //线程完成的事件
*
* theInfo.evtReset = manualEvents[i];
*
* theInfo.iReqNumber = i; //跟踪这是什么请求
*
* theInfo.strUrl = httpSite; // 要打开的URL
*
* ThreadPool.QueueUserWorkItem(ThreadProc, theInfo); //让线程池来完成这项工作
* }
*
* //等待直到ManualResetEvent被设置，这样应用程序在调用回调之后才会退出。
* //这里最多可以等待64个句柄。
* WaitHandle.WaitAll(manualEvents);*/
sw.Stop();
Console.WriteLine($"done! Time {sw.ElapsedMilliseconds}");
}
