Question

I have written a basic signalr hub that accepts a call from a client, updates the database and then pings a notification out to all clients.

public class ElementHub : Hub
{
    public void RenameElement(Guid elementId, string elementName)
    {
        //save details of rename

        //notify clients
        Clients.elementRenamed(elementId, elementName, DateTime.Now);
    }
}

This works perfectly on my development machine – all updates are instantaneous (near enough) – but when I publish this to Windows Azure website I start to see some odd behaviour.

After publication, the first notification that passes through the hub is still pretty much instantaneous – maybe a seconds delay. But the second notification is sometimes delayed by as much as 30 seconds!

I’ve included the server timestamp in the notification so I can confirm that the server is responding quickly enough. The problem is presumably somewhere in the transport.

I’m new to signalr so I don’t really even know where to look. Can anyone suggest what might be causing this behaviour or how I can debug it?

Answer 1

There’s a bug right now with buffering and Azure Websites, see http://github.com/SignalR/SignalR/issues/510. You can work around this for now by using longpolling. We’re working on this in the meantime.