WCF服务超时，然后执行操作？

Question

Ok, I have a WCF service, which is behaving in a pretty awkward way. The thing is, when I make the call to the service method, like this:

using (var wcf = new Wcf<IDroneService>("http://test.group.com/DroneService.svc"))
{
    wcf.Channel.StartLoadTest(scenario);
}

Nothing happens until the request times out after a minute, but then, and only then, after the exception has been thrown, the WCF service (hosted in IIS) starts, that is, actually loads its assemblies, and runs Application_Start, instances the service endpoints on the server side, etc. and it goes on to properly receive the request, and execute it . But this only happens AFTER the request has timed out and an exception has been thrown.

This is how I configure both my client and server bindings:

public class WcfConfigurator
{
    public Binding GetBinding()
    {
        var basic = new BasicHttpBinding
        {
            MaxBufferSize = int.MaxValue,
            MaxBufferPoolSize = int.MaxValue,
            MaxReceivedMessageSize = int.MaxValue,
            TransferMode = TransferMode.Streamed,
            ReceiveTimeout = TimeSpan.FromSeconds(30),
            ReaderQuotas =
            {
                MaxDepth = int.MaxValue,
                MaxStringContentLength = int.MaxValue,
                MaxArrayLength = int.MaxValue,
                MaxBytesPerRead = int.MaxValue,
                MaxNameTableCharCount = int.MaxValue
            }
        };
        return basic;
    }

    public void ConfigureBehavior(ServiceEndpoint endpoint)
    {
        foreach (OperationDescription op in endpoint.Contract.Operations)
        {
            var dataContractBehavior = op.Behaviors.Find<DataContractSerializerOperationBehavior>();
            if (dataContractBehavior != null)
            {
                dataContractBehavior.MaxItemsInObjectGraph = int.MaxValue;
            }
        }
    }

    public void ConfigureBehavior(KeyedByTypeCollection<IServiceBehavior> behaviors)
    {
        var serviceDebugBehavior = behaviors.Find<ServiceDebugBehavior>();
        if (serviceDebugBehavior != null)
        {
            serviceDebugBehavior.IncludeExceptionDetailInFaults = Config.Wcf.ExceptionDetails;
        }
    }
}

I use that same programmatic configuration on the server side, to build the endpoints. This issue only arises from big envelopes, this is not a problem for smaller envelopes.

Am I missing something in my configuration of the Wcf channel? Wcf<T> is just a wrapper around ChannelFactory.CreateChannel ; on the WCF server I configure it programmatically as well, with the Windsor WcfIntegration facility. Like this:

public override ServiceHostBase CreateServiceHost(string constructorString, Uri[] baseAddresses)
{
    ServiceHostBase serviceHost = base.CreateServiceHost(constructorString, baseAddresses);
    return ConfiguredServiceHost(serviceHost);
}

private T ConfiguredServiceHost<T>(T serviceHost) where T : ServiceHostBase
{
    serviceHost.AddDefaultEndpoints();

    wcfConfigurator.ConfigureBehavior(serviceHost.Description.Behaviors);

    foreach (ServiceEndpoint endpoint in serviceHost.Description.Endpoints)
    {
        endpoint.Binding = wcfConfigurator.GetBinding();
        wcfConfigurator.ConfigureBehavior(endpoint);
    }
    return serviceHost;
}

Although I don't believe this to be a server-side problem (at least not so far anyway), because like I said, symbols for the WCF server don't even load if the envelope is too big (until the request times out, and its processed anyways).

Has anyone come across this weird issue before?

Answer 1

From my experience with WCF - WCF errors are hard to predict and diagnostic, deep investigation required with extensive logging and WCF tracing enabled in place. I feel there is some misconfiguration on client/server service timeouts. SO install latest version of Fiddler, see what is going on, which requests were sent, whether response was sent or not. Also enable WCF tracing with switchLevel="All" , in most cases WCF trace log explicitly point you to an issue.

You mentioned 1 minute...

Timeouts in WCF and their default values

These are the most well known timeouts. SendTimeout , ReceiveTimeout , OpenTimeout and CloseTimeout . They can be set easily either through config or code on the Binding. The default value for those are 1 minute

Try out increasing its values explicitly, but as first thing I would recommend understand what is the issue, why it is appear, because 1 minute to estblish connection is pretty enough.

Answer 2

I have had similar issues before with WCF and it led me to using the ChannelFactory when consuming a service. I know it doesn't explain your error, but maybe it's worth trying. Here's how I did it:

internal static class ServiceObjects
{
    public static ISomeService SomeSVC { get { return GetSomeServiceClient(); }

    private static BasicHttpBinding _Binding = new BasicHttpBinding("SomeBasicHttpBindingEndpoint"); 
    private static EndpointAddress _Endpoint = new EndpointAddress(new Uri("http://test.helloworld.com/SomeService.svc"));

    private static IDocManagerService GetDocServiceClient()
    {
        ChannelFactory<ISomeService> _someSvcFactory = new ChannelFactory<ISomeService>(_Binding, _Endpoint);

        foreach (OperationDescription op in _someSvcFactory.Endpoint.Contract.Operations)
        {
            DataContractSerializerOperationBehavior _dataContractBehavior = op.Behaviors.Find<DataContractSerializerOperationBehavior>() as DataContractSerializerOperationBehavior;

            if (_dataContractBehavior != null)
            {
                _dataContractBehavior.MaxItemsInObjectGraph = int.MaxValue;
            }
        }

        return _someSvcFactory.CreateChannel();
    }
}

And consume the service:

ServiceObjects.SomeSVC.SomeMethod()