WCF Service Throttling

Question

I have a WCF service deployed in a console app with BasicHTTPBinding and SSL enabled. The following attribute is set as well:

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]

I have also set the throttling behavior to

<serviceThrottling maxConcurrentCalls="2147483647" maxConcurrentSessions="2147483647"
        maxConcurrentInstances="2147483647" />

On the other hand I have created a test client (for load test) that initiates multiple clients simultaneously (multiple threads) and performs transactions on the server. Everything seems fine but on server the CPU utilization doesn't increase so I added some logging to view the number of concurrent calls to the server and found that it never went over 6.

I have reviewed the performance counter logging code more than twice and it seems fine to me.

So I want to ask where is the problem in this situation? I haven't specified any kind of ContextMode or ConcurrencyMode yet.

After this Post I noticed that whenever i start another Intance of Test Client my concurrent Server Calls counter increase to 2 like if i am running only 1 instance the maximum Concurrent Rcvd Calls will be 2 and if there are two instance the same value goes to 4 and so on. Is there any limit of Number of WCF Calls from once process?

********Added on 17-March********

Today I ran another test with one test client (with 50 concurrent users) on the same machine on which the server is running. This time I am getting the exact result what I wanted it to show (i.e. Maximum concurrent Calls Rcvd by Server = 50).

But I need to do it the same on others machines as well. Can anybody help me on this?

Answer 1

I found a solution: there is a connection limit on ServicePointManager that was causing this problem. To remove this limit you just need to set

System.Net.ServicePointManager.DefaultConnectionLimit = X;

where the default limit is 2.

Answer 2

Or use this configuration in the client.

<system.net>
    <connectionManagement>
      <add maxconnection = "200" address ="*" />
    </connectionManagement>
  </system.net>

Here 200 is the limit from the client