wcf - 什么限制了 WCF ServiceModelService.Instances？

Question

我正在尝试使用(IIS6/Server2003/BasicHttpBinding)对 WCF 服务进行负载测试。该服务的限制如下:

<serviceThrottling maxConcurrentCalls="100" maxConcurrentSessions="100" maxConcurrentInstances="100"/>

为了评估服务器上的调用次数，我使用了 ServiceModelService 3.0.0.0 性能计数器。如果我将 maxConcurrentCalls 限制为 20、15、10 或任何更低的 Instances 性能计数器，则表明 WCF 正在遵守限制。但是，如果我将 maxConcurrentCalls 更改为 30，我将永远无法让 Instances 超过 24。此外，未完成调用永远不会超过 24。还有什么可能限制 WCF？

Answer 1

见 Why Only Two Concurrent Requests for WCF Load Testing?

When I looked at this question, my first response is that: the client did not really send enough requests to the server. Why is that? Here are the reasons:

1) If you use the synchronous WCF HttpModule/HttpHandler (installed by default), you would get the maximal number of concurrent requests (held by that number of ASP.NET worker threads) as 12 * [Number of CPU for the Server].

2) WCF throttling is specified above.