问题描述
我运行到使用实现IHttpAsyncHandler通用处理器的一些性能问题。最简单的处理程序接收一个GET请求，20秒后结束后写'＆LT的反应;超时/>'到响应。
在与10000-20000同时请求锤击ashx的，它无法与503服务器precisely 5000请求后不可用。当切换到同步模式，并立即结束的请求，问题消失。
我修修补补了一些设置，但我已经成功地acheive较低在发生这个错误请求门槛。唯一
这里是我已经玩弄设置一个破败的：
machine.config中：
＆LT;结构＆gt;
...
＆LT;＆的System.Web GT;
...
＆LT;中processModel启用=真requestQueueLimit =10000/＆GT;
...
的web.config：
＆LT;结构＆gt;
...
＆LT;＆的System.Web GT;
...
＆LT;的httpRuntime启用=真正的AP prequestQueueLimit =10000/＆GT;
...
IIS管理器> ApplicationPools>高级设置
队列长度：65535
虽然我不能肯定，好像这些设置工作好和细如果请求是同步的，但是当异步，我似乎无法获得超越5000完全相同请求的服务器开始告诉我走开之前。如果我设置的东西较低（不记得到底是哪设置，这将是从上面的，但我已经试过所有），那么503计数上升相应的，但我从来没有停止它的时候严重负荷下发生超越5000
似乎有一些散在的可能影响这个地方了无数的设置，但5000似乎相当一成不变的。我看<一个href=\"http://74.125.77.132/search?q=cache:Rw6hb12Ac94J:www.duringlunch.com/file.axd%3Ffile%3DAdvanced%2BASP.Net%2B2.ppt%2Bap$p$pquestQueueLimit%2B%22up%2Bto%22%2B5000&hl=en&ct=clnk&cd=1&gl=uk&client=firefox-a\">here该AP prequestQueueLimit不能超过5000，但可以找到有关此没有进一步的信息，并知道这是误传。
有什么样的防洪在IIS中设置可能被限制在单个主机不超过5000的请求？我怎样才能获得IIS来处理更多的并发5000异步请求？
EDIT2：是否有其极限可能会超出任何柜台或其他指标，我怎么会进一步调查
？编辑：这里是loadgenerator code：
使用系统;
使用System.Net;
使用的System.Threading;命名空间HammerTime
{
类节目
{
私有静态诠释柜台= 0;
静态无效的主要（字串[] args）
{
VAR上限= 5000;
ServicePointManager.DefaultConnectionLimit =限制;
的for（int i = 0; I＆LT;限制; ++ I）
{
StartWebRequest（i.ToString（））; }
到Console.ReadLine（）;
} 私有静态无效StartWebRequest（字符串的channelID）
{
字符串URI =HTTP：//spender2008/test/Test.ashx通道=+的channelID;
HttpWebRequest的要求=（HttpWebRequest的）WebRequest.Create（URI）;
request.BeginGetResponse（ResponseHandler所，请求）;
} 私有静态无效ResponseHandler所（IAsyncResult的AR）
{
尝试
{
HttpWebRequest的状态=（HttpWebRequest的）ar.AsyncState;
HttpWebResponse响应=（HttpWebResponse）state.EndGetResponse（AR）; }
赶上（例外五）
{
Console.WriteLine（e.Message）;
}
最后
{
Console.WriteLine（Interlocked.Increment（参考计数器））;
} }
}
}
确定。修正了......非常感谢职务。
要消除所需的503错误3种不同配置的变化：
machine.config中：
＆LT;结构＆gt;
...
＆LT;＆的System.Web GT;
...
＆LT;中processModel启用=真requestQueueLimit =100000/＆GT;
IIS管理器> ApplicationPools>高级设置
队列长度：65535
和最后（缺少一块拼图），在命令行：
Appcmd.exe的设置配置/条：serverRuntime中/ appConcurrentRequestLimit：100000
在主帖中提到的web.config中的设置是不相关的。
10000并行连接，没有任何问题。感谢您的帮助！
I'm running into some performance issues using a generic handler that implements IHttpAsyncHandler. At its simplest, the handler receives a GET request, and 20 seconds later ends the response after writing '< timeout / >' to the response.
When hammering the .ashx with 10000-20000 simultaneous requests, it fails with 503 server unavailable after precisely 5000 requests. When switching to synchronous mode, and ending the request immediately, the problem goes away.
I've tinkered with a number of settings, yet the only thing I've managed to acheive is lower the request threshold at which this error occurs.
Here's a rundown of the settings I've toyed with:
machine.config:
<configuration>
...
<system.web>
...
<processModel enable="true" requestQueueLimit="10000"/>
...
web.config:
<configuration>
...
<system.web>
...
<httpRuntime enable="true" appRequestQueueLimit="10000"/>
...
IIS Manager > ApplicationPools > Advanced Settings
Queue Length : 65535
Although I can't be sure, it seems like these settings work good and fine if the requests are synchronous, but when async, I can't seem to get beyond exactly 5000 requests before the server starts telling me to go away. If I set things lower (can't remember exactly which setting that would be from the above, but I've tried them all), then the 503 count goes up accordingly, but I can never stop it happening beyond 5000 when under serious load.
It seems that there a a number of settings scattered in a myriad of places that might affect this, but the 5000 seems fairly set in stone. I see here that appRequestQueueLimit cannot exceed 5000, but can find no further info about this, and wonder if this is misinformation.
Is there any kind of "flood-control" setting in IIS that might be limiting a single host to no more than 5000 requests? How can I get IIS to handle more that 5000 concurrent asynchronous requests?
Edit2: Are there any counters or other indicators of which limit might be being exceeded, and how would I investigate further?
Edit: Here's the loadgenerator code:
using System;
using System.Net;
using System.Threading;
namespace HammerTime
{
class Program
{
private static int counter = 0;
static void Main(string[] args)
{
var limit = 5000;
ServicePointManager.DefaultConnectionLimit=limit;
for (int i = 0; i < limit;++i )
{
StartWebRequest(i.ToString());
}
Console.ReadLine();
}
private static void StartWebRequest(string channelId)
{
string uri = "http://spender2008/test/Test.ashx?channel="+channelId;
HttpWebRequest request = (HttpWebRequest) WebRequest.Create(uri);
request.BeginGetResponse(responseHandler, request);
}
private static void responseHandler(IAsyncResult ar)
{
try
{
HttpWebRequest state = (HttpWebRequest)ar.AsyncState;
HttpWebResponse response = (HttpWebResponse)state.EndGetResponse(ar);
}
catch(Exception e)
{
Console.WriteLine(e.Message);
}
finally
{
Console.WriteLine(Interlocked.Increment(ref counter));
}
}
}
}
OK. Fixed... many thanks to this post for clearing up a few details.
To eliminate the 503 errors required 3 different config changes:
machine.config:
<configuration>
...
<system.web>
...
<processModel enable="true" requestQueueLimit="100000"/>
IIS Manager > ApplicationPools > Advanced Settings
Queue Length : 65535
and finally (the missing piece of the puzzle), the command line:
appcmd.exe set config /section:serverRuntime /appConcurrentRequestLimit:100000
The web.config setting mentioned in the main post was irrelevant.
10000 concurrent connections, no problems. Thanks for help!
这篇关于IIS 7.0 503错误与通用处理器（ashx的）执行IHttpAsyncHandler的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！