Question

I’ve developed a WCF service, and I’m testing it for performance using Visual Studio 2010 Load Testing infrastructure. I have a Quad Core Intel Q6600 on my desktop and, for now, the WCF is hosted on a console application for testing purpose. While executing the tests, I have 1 core at 100%, and the other 3 between 25 to 60%. The HostApplication.exe process for only brief instances passes 25%, and I don’t know why. Why isn’t WCF spreading the calls to the other cores, so that I don’t have a CPU bottleneck? Shouldn’t I have the HostApplication.exe spread over more than 1 core, limited at 25%?
I have configures VS2010 Load Testing with 25 users, and they are calling 2 methods. On the service implementation of the Methods I use, I have the following configured for ServiceBehaviour:

  [ServiceBehavior(TransactionIsolationLevel = System.Transactions.IsolationLevel.ReadCommitted, 
    InstanceContextMode=InstanceContextMode.PerCall, ConcurrencyMode=ConcurrencyMode.Multiple, ReleaseServiceInstanceOnTransactionComplete=false)]

I’ve also defined the serviceThrottling behaviour for the service. Below is my app.config:

  <system.serviceModel>
      <serviceHostingEnvironment aspNetCompatibilityEnabled="true" />
        <bindings>
            <basicHttpBinding>
                <binding name="SimpleBinding" />
            </basicHttpBinding>
            <netTcpBinding>
              <binding name="DefaultTCPBinding" closeTimeout="01:00:00" receiveTimeout="01:00:00"
                    sendTimeout="01:00:00" transactionFlow="true" transactionProtocol="OleTransactions"
                    maxBufferSize="5242880" maxReceivedMessageSize="5242880">
                <reliableSession inactivityTimeout="01:00:00" />
              </binding>
            </netTcpBinding>
            <webHttpBinding>
                <binding name="ScriptBindig" crossDomainScriptAccessEnabled="true" />
            </webHttpBinding>
        </bindings>
        <behaviors>
              <endpointBehaviors>
                    <behavior name="WebScriptBehavior">
                          <enableWebScript />
                    </behavior>
              </endpointBehaviors>
              <serviceBehaviors>
                    <behavior name="MetadataBehavior">
                          <serviceMetadata httpGetEnabled="true" httpGetBinding="webHttpBinding"
                                httpGetBindingConfiguration="" />
                          <serviceDebug includeExceptionDetailInFaults="true" />
                          <serviceThrottling maxConcurrentCalls="64" maxConcurrentSessions="400"
                                maxConcurrentInstances="464" />
                    </behavior>
              </serviceBehaviors>
        </behaviors>
        <services>
              <service behaviorConfiguration="MetadataBehavior" name="Implementation.TestingAppImplementation">
                    <endpoint address="" binding="netTcpBinding" bindingConfiguration="DefaultTCPBinding"
                          name="TestingAppTCPEndpoint" contract="Interfaces.ITestingApp" />
                    <endpoint address="mex" binding="mexHttpBinding" bindingConfiguration=""
                          name="TestingAppMex" contract="IMetadataExchange" />
                    <endpoint address="ws" behaviorConfiguration="" binding="basicHttpBinding"
                          bindingConfiguration="SimpleBinding" name="TestingApp" contract="Interfaces.ITestingApp" />
                    <host>
                          <baseAddresses>
                                <add baseAddress="net.tcp://desk01:9878/TestingAppService" />
                                <add baseAddress="http://desk01:9876/TestingAppService/" />
                          </baseAddresses>
                    </host>
              </service>
        </services>
    <diagnostics>
      <messageLogging logEntireMessage="true"
                      logMalformedMessages="true"
                      logMessagesAtTransportLevel="true" />
    </diagnostics>
  </system.serviceModel>

Tks so much for any help. ANY advice would be greatly appreciated.

Answer 1

After I transfered the WCF service from a self-hosting executable to IIS/AppFabric, with the same exact code and database modeling, I was able to use all 4 cores without a problem. I got great performance after transferring.
Tks