Streaming at LOW bitrate using RESTful WCF service

I want to continuously stream data at a very low bitrate : a few bytes per second.

My WCF REST service works fine when I stream a large amount of data. But when the bitrate is low, it seems that the stream is buffered until there is enough data to pass to the transport layer.

As a result, I receive 16Ko of data every 16 sec instead of 1Ko every sec.

How can I implement low bitrate streaming in WCF REST?

My WCF service:

void StartMyWCFService()
{ 
    host = new WebServiceHost(typeof(IServ), n开发者_如何学运维ew Uri("http://localhost:4530/");
    var bnd = new WebHttpBinding();
    bnd.TransferMode = TransferMode.Streamed;
    host.AddServiceEndpoint(typeof(IServ), bnd, "");
    host.Open();
}


[ServiceContract]
public interface IServ
{
    [OperationContract, WebGet(UriTemplate = "/")]
    Stream MyStream();
}

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
class Serv : IServ
{
    public Stream MyStream()
    {
        var resp = WebOperationContext.Current.OutgoingResponse;
        resp.StatusCode = System.Net.HttpStatusCode.OK;
        return _new MyStream();
    }
}

class MyStream : Stream
{
    public override int Read(byte[] buffer, int offset, int count)
    {
        // returns a few bytes every second
    }
    [...]
}

Edit: I noticed a 16Ko hardcoded buffer size deep inside .net framework (v4) at: System.ServiceModel.dll#System.ServiceModel.Channels.HttpOutput.WriteStreamedMessage()

Thanks

You may be able to work-around the buffering by returning an IEnumerable of byte arrays instead of a stream, and sending a byte[1024] or less each time.

I've got a answer from MS. The stream is sent by 16ko/32ko chrunk. This behavior is "by design".

More info: http://social.msdn.microsoft.com/Forums/en/wcf/thread/0662dc2e-6468-47c5-9676-fa14a56121cb