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named pipe callback takes 10 seconds?

got wcf dll with client and server classes wraping it.
when my server uses callback it takes over 10 seconds for my client to get it..
what is going on?
only got simplest NetNamedPipeBinding endpoint.
got lots of code so I'm not sure what to paste here.
what can cause such a long time.
EDIT:
only first callback takes 10 seconds..
after this it works fast.
any one knows why?

I had similar problem. This helped in my case:
NetNamedPipeSecurity security = new NetNamedPipeSecurity() { Mode = NetNamedPipeSecurityMode.None };
Pass this security object when creating the binding:
new NetNamedPipeBinding() { Security = security }
The original idea is from here. The thread was about TCP binding, but the solution presented at the end appeared to be helpful for named pipes too in my case.
Even simpler is to do:
new NetNamedPipeBinding(NetNamedPipeSecurityMode.None)

Nothing helped. I ended up to add a fake call decorater. that sends the first call when the system is booting.

Accidentally I found a setting that greatly improves performance of the first WCF request. The time came down from > 10 seconds to ~2 seconds.
Set binding's TransferMode property to Streamed both on server and client:
var binding = new NetNamedPipeBinding(NetNamedPipeSecurityMode.None);
binding.TransferMode = TransferMode.Streamed;
Then pass the binding into AddServiceEndpoint server-side and into Channelfactory constructor client-side.

How are you hosting your service? The first call will need to create the service which can be slow to startup.
When debugging I use Studio's built in service host, and this often takes several seconds to sort itself out. Don't think I've ever seen it take 10 seconds mind.

Is there an example of checking on if a WCF Service is online? [duplicate]

This question already has answers here:
check the availability of the WCF Web Service
(4 answers)
Closed 8 years ago.
I will have a client application using a proxy to a WCF Service. This client will be a windows form application doing basicHttpBinding to N number of endpoints at an address.
The problem I want to resolve is that when any windows form application going across the internet to get my web server that must have my web server online will need to know that this particular WCF Service is online. I need an example of how this client on a background thread will be able to do a polling of just "WCF Service.., Are You There?" This way our client application can notify clients before they invest a lot of time in building up work client-side to only be frustrated with the WCF Service being offline.
Again I am looking for a simple way to check for WCF Service "Are You There?"

What this obsession with checking whether those services are there??
Just call the service and as any defensive programming course will teach you, be prepared to handle exceptions.
There's really no benefit in constantly sending "are you there?" requests all over the wire...
Even if you could have something like a Ping() method (that just returns a fixed value or something - your service name or whatever) - that only checks whether your service is reachable - what about the database you need to query to get data from? What about other services your service method depends on? It gets quite messy and very very tricky to figure out a way to check all that - just to see if it's there.
In brief: no, there is no reliable and meaningful way to check whether a given service is "there" and "alive" - just call it ! And be prepared to handle a failure - it will fail at times....

There is no value in checking if a service is alive or not. Absolutely none. Why?
if(serviceIsAlive())
{
callService();
}
else
{
handleFailure()
}
Do you see the problem with this snippet? What happens if between the time you check if the service is alive, and the time you call it, the service goes down? This is a race condition, and a bug waiting to happen. So what you need to do, even if you can check the service condition, is:
if(serviceIsAlive())
{
try
{
callService();
}
catch(CommunicationException)
{
handleFailure();
}
}
else
{
handleFailure();
}
But in this block, the handleFailure() call is in two different places - we've got two different paths to handle the same error condition - which seems like a bad thing. So this can be safely reduced to:
try
{
callService();
}
catch(CommunicationException)
{
handleFailure();
}

If your service is hosted in IIS (or WAS), you can perform a resiliency built-in to the IIS6/7 process model. If an worker process fails, another will be started in its place. How it works? Using Ping to analyse. Its called AppoPool Health Monitoring (described here).

CommunicationException with 'not recognized sequence' message in WCF

I get a CommunicationException while using WCF service. The message is:
The remote endpoint no longer recognizes this sequence. This is most likely due to an abort on the remote endpoint. The value of wsrm:Identifier is not a known Sequence identifier. The reliable session was faulted.
The exception is thrown in a moment after a contract method was called. Before calling contract method the channel state is Opened. I restore my service client after catching this exception and for some time it works fine. But then this error occures again. It seems like some timeout is exceeded, but I can't understand which one exactly.
I use wsHttpBinding with reliableSession enabled. The InactivityTimeout is set to half an hour and I'm sure it's not exceeded, because exception is thrown earlier.

I solved the problem. The reason was RecieveTimeout on a server side. It was set to 1 minute, so after having no requests during 1 minute server used to close a channel, and when client tried to call a contract, channel was already crashed due to the timeout.
I found the solution after reading this article:
http://msdn.microsoft.com/en-us/library/system.servicemodel.reliablesession.inactivitytimeout.aspx

I received this error while setting up a new WCF service which returned a list of objects.
My understanding is that WCF services can only pass very simple objects back n forth.
So objects with anything other than public properties will not be transferable.
The object had a read only property doing a bit of logic.
Once I got rid of this, rebuilt, and updated the web references, the error went away.

Tip:
If you're returning a object and it has properties check the gets and sets of each one.
We had a problem around it.

I have seen this happen when an application pool gets recycled.
Look at the very last section of this blog about service recycling .

Silverlight and WCF: NotFound error!

I have WCF method like so:
public string GetSomething(MyObject obj)
{
return "Something";
}
When I call this from my silverlight app I get an error:
System.Net.WebException: The remote server returned an error: NotFound.....
I call the method from my silverlight app like so:
mProxy.GetSomethingAsync(new MyObject());
Now, when I call the method like this it works fine:
mProxy.GetSomethingAsync(null);
So there seems to be some problem with passing in a complex object.
Note that I return this MyObject from other method and it works fine so it's not a serializable issue. I also changed the maxBufferSize and maxReceivedMessageSize to the max value so it's not that, and i pass in an empty object anyway so it shouldn't be a size issue. And MyObject only contains simple datatypes.
Has anyone any suggestions?

That "Not Found" error is perhaps the single most annoying feature of Silverlight WCF access.
You may want to look into the Service Trace Viewer Tool (here). It's not always helpful (I've run into lots of problems that it wasn't able to help with), but about 10-20% of the time, it'll point me in the right direction.
You may also want to try adding the SilverlightFaultBehavior to your service. It can turn at least some of those "Not Found" error messages into real faults.

I have used the WcfTestClient.exe to debug my WCF services. It gives a much more user friendly error message. If you want to set up Silverlight to receieve WCF faults, I found this page on Data Performance and Fault Strategies in Silverlight 3
to be helpful.
(http://msdn.microsoft.com/en-us/magazine/ee294456.aspx)

Can an WCF Service create his own host?

I have a client / server type of application and I'd like the server object to create his own host. It looks something like this:
public class Server : IServer {
private ServiceHost m_Host;
public Server() {
m_Host = new ServiceHost(this);
m_Host.Open();
}
}
It seems to work fine when there are few message transfers occurring. But when it starts to speed up (my application requires that data is transfered every 50 ms), the server hangs and and the transfers stop after a few seconds without throwing an exception.
So, is it possible for an object to create his own host? Or do I really have to create it in the main() or do something else?
EDIT: I think the problem in this case is that I want the object that implements the service itself to create his own ServiceHost.

There's nothing really stopping any object to create an instance of ServiceHost.
The big question then is - can you guarantee that your object containing the service host is "alive"? Or was it garbage collected by any chance?
We use Windows (NT) Services to host our own custom service host classes to provide around-the-clock availability for WCF services - works just fine.
Marc

To be a WCF service it simply needs to implement the service contract. There's nothing to stop you adding more methods to open and close an instance of itself as a service.

Check out the ServiceBehaviorAttribute which allows you to specify how your service ... behaves. ;) The ConcurrencyMode property defined the support for multithreading and defaults to single threaded mode, and the InstanceContextMode defines if the service object is per session, per call or singleton.
Quote from ConcurrencyMode:
Setting ConcurrencyMode to Single instructs the system to restrict instances of the service to one thread of execution at a time, which frees you from dealing with threading issues. A value of Multiple means that service objects can be executed by multiple threads at any one time. In this case, you must ensure thread safety.
Quote from InstanceContextMode:
If the InstanceContextMode value is set to Single the result is that your service can only process one message at a time unless you also set the ConcurrencyMode value to Multiple.
We could really use some code examples of your service to further debug the behavior you're describing. For example, is your service object expensive to construct (assuming non singleton implementation), or do the operation slow down? Do you know where the time is spent, is it code, or could it as well be some firewall that limits connection? What protocol do you use?